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Forum Index : Solar : Deciding if I should build this solar heater

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rogerdw
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Joined: 22/10/2019
Location: Australia
Posts: 852
Posted: 02:36pm 08 Aug 2021
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  Davo99 said  Sounds brilliant.  The independence would be worth it alone.
Do you have a Generator? If you had one you could go totally off grid. I know a bloke that could tell you everything you needed to know and bore you to tears with a lot more about running a Diesel engine long term reliably off Veg oil you can get for nothing to power a genny.


Hah! I was going to say no  ... but I just remembered I bought an old Honda 5kVa Dunlite generator at an auction last year.

King of the cheapskates, it cost me $70  ...  but of course it didn't go. I put in fresh fuel and tidied things up  ...  and eventually after I cleaned and reset the points the motor ran just fine. The generator didn't run either  ...  and I found some crook components on the regulator board. Replacing them fixed that as well. I've fired it up a few times but haven't used it for any serious purpose yet.

I don't see it being a serious backup genny because it is so old and I don't know how reliable it would be  ...  but I would possibly trade up to something more suitable.


  Quote  I am nuts and Bolts away from Completing my 10 Kw to get it operational at least. Still have to do the sound deadening and the exhaust .  I think I am gong to start " Exercising" at Bunnys and the exhaust shop or this thing will be sitting round till next freaking year and it WON'T be my fault or Procrastination for once.


Sorry to hear you're still going through all that. We have been so lucky over here  ...  even with this last 7 day shutdown I was still able to get out and about quite well (legitimately)  ...  not that I ever need to go far.



  Quote   No, I wouldn't be at all concerned but at that point you'd probably do well to see if you could find whom had the  lowest daily Ripoff,,,,, errr, Supply charge if you want the grid as back up.  Especially with everything going on now, I would Highly doubt even more they would question anything.


Thanks  ...  in the past I would have been concerned about doing something like this  ...  but I've changed my mind and not fussed about it anymore. And I know that our power bill is less than half of what it was 6 years ago when we first came here. Of course a couple of teenage daughters leaving home helped a fair bit there  ...  and then the pool pump changes.


  Quote  Last thing you want in the world is to be like that Nut case!! I wouldn't want to be like him if I remotely had the choice.


Haha  ...  don't sell yourself short.

I had been watching facebook marketplace for ages for panels and was ready to jump on any bargains I could find  ...  though for the last month I've stayed off facebook to stop wasting so much time.

Perhaps I'll try gumtree again and see what's there  ...  the longer I can stay away from that other site the better.

There's always plenty for sale  ...  I'm probably hanging out for an absolute bargain  ...  which stops me pulling the trigger  ...  plus it always means a long drive to go pick them up.

I did miss one a couple years ago when a local sold a complete 5kW system for $200. I missed it by only a few minutes  ...  and what I should have done was offer them $500 and see if they'd sell it to me instead. When I'm ready for them, I'll have to jump in with both feet.


  Quote  Isn't that panel Recycling place is Adelaide? I doubt they would sell you any as they are up to their armpits with the corrupt solar industry but, worth a Phone call.
Tell them you are off Grid on the land and want them for pumps and battery backup for machinery located around the property.  You never know.


Good idea, I'll have to give that a try. Couldn't hurt.



  Quote  
I have been utterly astounded and deeply Humbled by the extremely kind and generous well wishes people have made. It was not expected in any way, quite the opposite really. I'm not exactly a soft guy but I have been shown a lot of good in people and the world that I had forgotten or become dismissive of.  It's really been humbling and an eye opener. I don't know about a celebrity, more a prize idiot but I consider myself very undeserving and fortunate to encounter the people I have there and in real life. I would never in a Million years thought anyone would be so interested in my stupidity but it seems it has helped a lot of people out more than even I knew so that is a very good upside.


Yes, it's easy to forget about the good and feel like it's all gone to hell in a handbasket  ...  but there are good people out there who care about others and want to lift them up. And I suppose we all downplay our skills and abilities and are surprised when people acknowledge us for them.

I think there's lots of people who are interested in things and would love to have a go  ...  but society, the PC crowd and the safety sissies have scared them off from having a go  ...  and then you come out and show em how it's done  ...  tell them to stuff the nay sayers and just do it anyway  ...  and make it sound like you don't have a clue (which I don't buy for a second)  ...  

...  all of which encourages others that it really isn't that difficult to try some of these experiments.

And it's pretty obvious from the comments that your videos have encouraged others to have a go and achieve great results  ...  you've given them the permission they didn't think they had.


  Quote  Was not a good time recently but geez, the vid comments and messages and what people I know said and did for us sure was incredible. I consider my self extremely fortunate to have found such incredible kindness and good will in people and never cease to be astounded and completely humbled by it.
Made me have a rethink on a lot of things especially my own outlook and attitude. I will try to better live up to the good other people have shown me.


Sorry to hear that, but glad to hear there may have been some good come of it. It's amazing how even a slight change in view of something can make all the difference.


  Quote  I thought I'll have a crack at doing something with the wood cutting when I go north.
See if I can make something entertaining out of that. I know well it's not as much the Oil burning people watch for, it's a pelican making an idiot of themselves so The subject matter is probably a bit irrelevant.


That's a great idea and I bet even the oil burner die hards will still love it. The bottom line is that your fans love your style, your irreverence and disdain for stupid regulations  ...  and idiots in general. They especially seem to love your sarcasm when it comes to 'safety tips'. Just keep giving them what they want, and they'll keep coming back.


  Quote  Was funny, when I did that last one, both the wife and daughter were working from Home that day. They were doing that video conferencing thing on their computers and both got asked multiple times where they near an airport or what was the jet engine roar and people yelling?


Haha, that's funny.


  Quote  Wonder how I'd go about Bangood sending me one for evaluation on my channel?


Who better to evaluate their gear than you  ...  you certainly are an expert on the topic and have a pretty decent following. Definitely worth asking..


  Quote  The fire risk is a big consideration  --------------

For me, the way to do it is put the thing outside. The real difficulty in doing a home heater to me is a heat exchanger.  That way I can employ my safety standard of  "Put the bastard where it can have a total meltdown and it's in a place where it can't do any damage and therefore I don't care".


Yes, I'm exactly the same. There's some things I wouldn't think twice about doing outside or even down the shed  ...  but the house  ...  that's gotta be kept safe no matter what.


  Quote  I don't need anything else to keep me away at night.


Exactly.


  Quote  The AEG in the pic is a battery saw. It's a ball tearer.  Will do anything a similar size Petrol saw will do and more. Dad has a couple in his collection so I can compare.


I didn't even realise they were a contender. Work a few points in your next video and you might score a new one to review.


  Quote  but he was obviously hell bent on buying another new toy


We're probably all pretty good at that, I know I can convince myself of all sorts of things when I decide I want a new 'toy'.

Like today  ...  went down to bunnings and picked up a set of those combination drill/taps  ...  Sutton ones. I'm sure I bought some cheapies on ebay once, but could only find an 8mm one and I wanted some 4 and 5mm ones for the sheet metal on this heater.

I had a couple $50 vouchers I scored when I looked at a guys ignition off his Ferrari. I couldn't find anything wrong with it and didn't charge him for my time  ...  and he mailed me these. Now every time I use them I'll remember the ferrari ignition.


  Quote  I have lost a lot of weight recently and a Hell of a lot of strength and Muscle and I'm feeling it.


I haven't lost any weight, but I certainly have lost a lot of strength. It may be a bit age related  ...  but I think it is as much my lifestyle  ...  I just don't do enough actually hard physical stuff anymore. What's the saying  ...  use it or lose it.


  Quote  I'm sure if your tubes save even 1 ton of wood next winter it will be worth while and lets face it, we aren't getting any younger or more capable of this work.... although I am having great difficulty trying to explain that to my father whom refuses to take it into account.


I'm pretty sure it will  ...  though the best part is it will do it every year for longer than I'm likely to be alive  ...  so that's a bonus.


  Quote  I bought him a Big Chipper a few months back. I have been wondering how it would go to spread a load of the chips out to dry them and how they would go thrown into the fire like Coal?  I have my reservations due to the lack of air around them but in an air controlled environment?


I had wondered about that sort of stuff. We have a couple of local businesses that do wood products of various kinds  ...  fence posts etc  ...  and end up with a lot of waste  ... sawdust and woodchips etc.
Cheers,  Roger
 
Warpspeed
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Joined: 09/08/2007
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Posted: 09:56pm 08 Aug 2021
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  Quote  The real difficulty in doing a home heater to me is a heat exchanger.


Dave, see if you can grab a secondhand Rinnai gas space heater to experiment with.

I now have seven of these, and they can sometimes be picked up very cheaply. I actually bought a fully working one for two dollars once. Fifty dollars might be more typical. I even have one blowing hot air into a tumble clothes dryer.

Anyhow, there is a sealed stainless steel combustion box with a gas burner inside, and a combustion blower that draws in outside air. After the combustion box there are three quite compact stainless steel heat exchangers, and the no longer very hot flue gas then gets vented outside.

If you pulled one to bits there might be some useful parts that could be repurposed for an oil burning space heater.

The main reason these Rinnai heaters get junked is that the control system uses a very large and complex circuit board with a microcontroller and a lot of different sensors. Once they start to give trouble, your average plumber and gas fitter is way out of his depth with the electronics. He will simply advise the customer to buy a new one.  So they sometimes appear on e-bay and gum tree at give away prices.
Cheers,  Tony.
 
Davo99
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Posted: 01:01am 09 Aug 2021
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  rogerdw said  

I don't see it being a serious backup genny because it is so old and I don't know how reliable it would be  ...  but I would possibly trade up to something more suitable.


Don't know what your Connection charges are but having a connection to the grid wouldn't be the worst thing for backup and piece of mind.  Certainly wouldn't be a bad idea at least for a year  while you got sorted and any bugs ironed out.

One thing  with the solar heater is you are collecting Data that can be transposed  to PV. My recommendation would be start with all the solar you can fit in your roof  and then consider a Ground mount setup as well if you need extra for winter.  You can always turn it off in summer or Get a used split AC system and run it in your shed.


  Quote   Of course a couple of teenage daughters leaving home helped a fair bit there  ...  and then the pool pump changes.


I have not worked out how much power my daughter costs us but in reality, I don't think it's much.  Hard to say, seems like she is never here these days but when she is, I'll bet her hourly consumption rate is quite high.

The pool pump would be a major Draw.  They run decent consumption at often long hours.  People talk a lot about the parasitic loss of those little power supply units and other things but I believe there is more benefit in going after the big loads first and eliminating/ minimising them.  Plus I am far too lazy and aggro to go round turning everything on and off all the time.  I don't even turn my computer off unless I am going away for a week or rebooting it for something.  Goes into standby after 15 Min and wakes up when I hit a key.  Not sure what it uses when it's sleeping but I don't care TBH.


  Quote  
I had been watching facebook marketplace for ages for panels and was ready to jump on any bargains I could find  ...  though for the last month I've stayed off facebook to stop wasting so much time.


Well done! That is something.  Something difficult and not to be dismissed lightly either. Changing ones habits be they significant or otherwise is not easy and should not be taken lightly.  



  Quote  There's always plenty for sale  ...  I'm probably hanging out for an absolute bargain  ...  which stops me pulling the trigger  ...  plus it always means a long drive to go pick them up.


I don't even buy them anymore unless they are brand new.... and then I pay little for them.  Supply  can vary place to place though. As with most things, I have found tenacity and gall are the deciding factors.  As my grandfather used to say, no hide no Christmas box. I have plenty of hide and am not scared to go talk to people and ask for what I want. I also understand the other perspective of the equation not just my own. That makes ALL the difference.

  Quote  I did miss one a couple years ago when a local sold a complete 5kW system for $200. I missed it by only a few minutes  ...  and what I should have done was offer them $500 and see if they'd sell it to me instead.


Offer MORE?? I think that's Illegal! Is in my book of tightarse Scroogeness  anyway!    My father seems to have gone from being horrified to amused how I negotiate and buy things for less. He's even started trying it and had a few good outcomes.

We always remember and kick ourselves for the ones that got away but I tend at least to forget the real wins I get.  Mostly anyway. I do try to give others some minor wins though. Amazing the effect giving someone an extra car part you have a stack of or chucking in an extra solar panel or 2 can do. I'm not a faithful person but I sure believe in karma. Clearly I have done a lot of bad things in my life.


  Quote  

Yes, it's easy to forget about the good and feel like it's all gone to hell in a handbasket  ...  but there are good people out there who care about others and want to lift them up. And I suppose we all downplay our skills and abilities and are surprised when people acknowledge us for them.

I think there's lots of people who are interested in things and would love to have a go  ...  but society, the PC crowd and the safety sissies have scared them off from having a go  ...  and then you come out and show em how it's done  ...  tell them to stuff the nay sayers and just do it anyway  ...  and make it sound like you don't have a clue (which I don't buy for a second)  ...  

...  all of which encourages others that it really isn't that difficult to try some of these experiments.

And it's pretty obvious from the comments that your videos have encouraged others to have a go and achieve great results  ...  you've given them the permission they didn't think they had.


That is very insightful and helpful. Thank you Roger.  Having an outside perspective
on things is Very important and really the secret to being successful in something.
A client, a world famous Behavioural Scientist as it turned out whom also became a dear friend gave me a heads up early on in doing my Glamour work.  The insight he gave me similar to yours made the world of difference to my success in that field.
I literally can do things and talk to Clients in a way others can't because I understand what they are really wanting where I have yet to come across anyone else that has the same insight.  Of course at first it was a bit difficult but then soon as you see it works and get the feedback, then it's a walk in the park.

Having the true customer perspective was an empowerment that allowed me to just walk over any opposition even when they were far better shooters than I because I understood what it was really about and what motivated clients. Unlike what everyone has ingrained in their Psyche, it was NOT the pictures.

I think what you said there is a similar gem of wisdom to keep in mind with this. I will print it out and put it in my ideas book because I think that's a real gem of info there. Thank you.


  Quote  
That's a great idea and I bet even the oil burner die hards will still love it. The bottom line is that your fans love your style, your irreverence and disdain for stupid regulations  ...  and idiots in general. They especially seem to love your sarcasm when it comes to 'safety tips'. Just keep giving them what they want, and they'll keep coming back.


Thank you again. Something else to keep in mind and I can use.
I was recently talking to a real big time Tuber who told me that he was initially very unsure about departing from his usual subject matter. He said he was struggling for content and this was completely a personal thing and he thought he'd throw it in for variety and as a filler.  He said the response he got was huge and now he's at least 50/50 that and his regular subject and the channel has grown faster than ever.

Once again, as you say, another example of not being about the "pictures" but the person and what they are representing and how they are connecting with their audience.   Understanding the core reasons is not at all easy when you are in the drivers seat but feedback and insight like that is worth its weight in gold x10.


  Quote  Wonder how I'd go about Bangood sending me one for evaluation on my channel?


Who better to evaluate their gear than you  ...  you certainly are an expert on the topic and have a pretty decent following. Definitely worth asking..

I have thought for a long time that my subject is pretty limited in advertiser direct appeal or sponsorship opportunities but this would be right on target.... as tiny a target as this is.



  Quote  I didn't even realise they were a contender. Work a few points in your next video and you might score a new one to review.


Yes, that is another good point.
I have seen  channels with far less subscribers than I have seem to get a lot of gear sent to them. Always the risk though. If I thought something was crap I'd say so and that would soon end the party.


  Quote  
We're probably all pretty good at that, I know I can convince myself of all sorts of things when I decide I want a new 'toy'.


Actually, I'm pretty good at talking myself out of buying things.  Probably too much so when I should just buy what I need and stop stuffing round and get the job done. I can't ever remember having regrets finally getting something I procrastinated about.

One thing I did want when I came here was a tractor. Everyone said that was just me wanting a new Toy.  Bought one for Dad locally  and then he changed his mind so bought it off him and was the best thing I ever did.  First weekend I had it was doing something for the Mrs with it and she later said " We should have got one of these before".  If looks could kill she would have been a pink mist on the wall behind her.



  Quote  
I haven't lost any weight, but I certainly have lost a lot of strength. It may be a bit age related  ...  but I think it is as much my lifestyle  ...  I just don't do enough actually hard physical stuff anymore. What's the saying  ...  use it or lose it.


I think that's it!
I was concerned about the new medication I'm on but I can't find anything listed as a side effect for that and they generally list every single thing anyone ever had while taking anything including ingrown toe nail. Unless it's a couple of recently popular vaXXXines of course where the listed side effects are far less than Aspirin, which is telling by the glaring omissions rather than what they do tell you.

I'm going to dig out some weights and set something up on some Pulleys on the back verandah as well as starting to take the Dog for a walk. When I used to go to the gym about 5 years back I could pull trees out the ground. I hated it but I cannot deny the good it did me.


  Quote  
I'm pretty sure it will  ...  though the best part is it will do it every year for longer than I'm likely to be alive  ...  so that's a bonus.


Yes, it is a very good long term investment. It's green and enviro friendly and all that good stuff and the upside is, if the environmentalists are right and the planet gets hotter, rather than wearing out and getting less effective, it will work even better in years to come!  
I'm all for Globull warming.  Gardens grow better in the warmer months and I hate the cold. If it's warmer the solar radiation must be higher so your tubes and my PV will work better as well. Personally, I fail to see a downside to it!  

  Quote  
I had wondered about that sort of stuff. We have a couple of local businesses that do wood products of various kinds  ...  fence posts etc  ...  and end up with a lot of waste  ... sawdust and woodchips etc.


I have watched a LOT of Videos about making sawdust and newspaper logs.
Looks like fun for a Video but I'd rather do wood than make enough of those to heat a house for a winter. They must live in Cairns or somewhere for that to be Viable where they need to heat one day a year.... or have a lot of time on their hands and need the exercise.  

That said, 2 thoughts I have had with that....
First would be instead of making the paper mache with water, what about using  Veg oil?  The water seems to take a LONG time to dry out and other than breaking the paper fibres up, serves no purpose.  Veg oil would allow the paper fibres to separate and then bind and would also add a LOT of heat energy to the Brick.  Veg oil will dry or more specifically, Polymerise  which makes it sticky to dry depending on how long it's cooked off and would bind the bricks very well.  No need to let them dry on the inside, they could be used at any point after they were made.  As I mentioned earlier, Oil has about 3 Times the heat value of wood so the energy in the bricks would have a BIG increase for zero extra effort. The bricks would act more like a Wick for the oil and from the size of the bricks I have seen people usually make, might be 200Ml of oil or more left in one which would be a VERY energy intensive bit of fuel for a fire.

Other thing was I wondering about was  Boiling/ Soaking wood.
I have tried this half heartedly and was unable to come to a conclusion.
I have 2 Thoughts, one is dry wood and the other is wet.  Boiling undried timber should force the moisture out like a giant potato chip and dry it. My test indicated this could take a long time but watched kettles and all that. The question would be energy input but If oil was used where it could not be used in the house or it was done with excess solar in the summer..... Again hard to do in the qty required but  may be worth while as starter or all nighter timber. If one did it in a 44 Gallon drum, production may not be that difficult if say a load a day was done where it could be loaded and then walked away from so hands on time was minimal.

Waiting till the wood stopped bubbling which is an indication the timber is dry would  be the measure.  It could then be removed or left to sit in the oil which it should absorb, again like a potato chip.  A test  to see which method was more effective would dictate the best procedure.

With Dry wood a Boil and then left to cool in it would probably work and again bump up the heat value significantly.

Doing wood chips should be very effective as there would be so much more surface area to dispel the moisture and absorb the oil. That would make the process much faster and more efficient. The chips would most likely be like a wick for the oil which would allow it to be used where it could not be otherwise.

The downside I see is with storage.  Oil will decompose like Lawn Clippings and generate heat. I have had a few cases of oily rags  starting to smoulder and caught it on vid too.  One of those things you hear about but never really believe till you see it.

I don't think the wood would pose much problem but the paper bricks and Chips may be something else.  As long as they are stored in a relatively air tight container away from other flammables they should not be a problem but you may come back in winter and open a drum to find a Pile of ash. Or it might be fine, lot of variables involved.
 
Davo99
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Posted: 01:06am 09 Aug 2021
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  Warpspeed said  

Dave, see if you can grab a secondhand Rinnai gas space heater to experiment with.


Would you have a Picture or model number I could refer to Tony?
The ones I have in mind would be quite different and I can't relate to the style you are talking about.

I also am aware of the sort of heating used down south is different to what we normally see here as is the cooling  up north very different.
I have seen those evap coolers everywhere in Qld but never remember seeing one in Sydney.

One thing I was thinking of was an Instant gas heater which are becoming far more popular here but I have yet to get my hands on one to dissect it and see how it could be used.
 
Warpspeed
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Posted: 02:24am 09 Aug 2021
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  Davo99 said  
Would you have a Picture or model number I could refer to Tony?


Could not find any ready pictures on the internet, so I pulled the covers off one I have working here. There are several very similar versions, all called "Rinnai Energy Saver".
There is a big one called model 1001 that has three gas burners, and a smaller two burner version called 551F.  Everything on the larger unit is scaled up in proportion but is otherwise they are functionally identical.

Here is what a 551F looks like with all the covers on:



And with the inner air plenum cover removed.
Room air comes in at the upper rear into the double ended blower, then blows straight down over the fire box and three heat exchangers, hot air emerging at the bottom.



The fire box is the large silver box in the middle, combustion air enters at the lower right from the centrifugal combustion air blower fed from outside air. Flue gas at the top of the fire box exits at both the top front, and top rear.

There are two primary heat exchangers, one in front and one behind the fire box. The one behind is not visible.  I have removed the front primary heat exchanger in the picture below, its made of stainless steel, and just plugs into both the fire box, and the secondary heat exchanger. The one at the back is identical.



Flue gas enters the secondary heat exchanger at both the front and back, and travels upwards then downwards in an inverted U shaped path. Final exit of the very much cooled flue gas is at the rear.

The combustion air blower is at the lower right of the firebox. And there is a small window to view the ignition spark, one end of the burner, and the flame detector.



That is about it. They work extremely well and very efficiently, the final flue gas is only warm. They are available for either natural gas or propane, the only difference being the size of the burner jet, which is easily changed from one to the other type of gas.

Most of the controls will be pretty useless to you, but the firebox, heat exchangers and air blowers should work just as well with a small oil burner, if you can rig up a suitable burner and controls. That would be beyond my own ability to get working properly, but I am sure the basic hardware which is quite well made, might give you some ideas.
Cheers,  Tony.
 
Davo99
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Posted: 08:13am 09 Aug 2021
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Thank You very much Tony for the pictures, Taking the trouble to dissect your heater and the explanation.  Very kind and much appreciated.

I have seen those heaters around but will keep an eye out for some now. There was one at the air BNB we stayed at in the Hunter valley a few months ago.  that thing was a real ball tearer. Don't know what Size it was,  I seem to recall it was a Rinnai and was on LPG but sure Kicked out the heat.

The HE is very simple isn't it?  That said, a layout I had not thought of. Wide and thin and blow the air both sides.  I can see by the dimpling pressed in its' designed to make the hot gas flow around a bit .

They seem to have updated the model numbers but the one closest to the 551 Does a useful 5.1 Kw and the big one does 8.6KW.

What I found really interesting looking at that was the area heating guide.

Heats upto Capacity (m2) : Very Cold 75
Heats upto Capacity (m2) : Cold 89
Heats upto Capacity (m2) : Cool 119
Heats upto Capacity (m2) : Mild 138

Now I don't know what the actual temperatures for their  Cold, cool etc specifications are but none the less, even the cold reference only specs an area slightly larger than my Kitchen and that's an open area which leads to the smaller lounge room which would make the total about what they spec and then of course is the attached hallway  which can't be closed off.

I found a heating product selector and punched in the requested specs and my location  and it came back with reccomending the big 8.6 Kw heater so they must think it's cold enough here for that amount of energy input. I only put in the kitchen area which puts the recommendation into the very cold category. I wonder if I put in the whole house area if they would say I needed 3 or 4 of them?  


8.6 Kw pumped into an area that size is a LOT of energy to my way of thinking so maybe this place and the energy I'm putting into it isn't so bad after all?
I am figuring 10 Kw for the whole house distributed with the AC fan.  Either very cold is constant snow or they are talking about running a place a lot warmer than I have this one as a normal thing. Maybe I'll need more than I think for the whole house?  I wouldn't be disappointed, my problem is building a heater small enough  but if I could modify one of these, I'd be OK having something that was a production unit and looked good in the house and I could easy  incorporate some shutdown sensors.

Given what I have done with the Diesel and fan heaters this winter, I think 8 KW would be OK, might just have to run it 24/7 in the coldest parts but I would have no problem with that at all either.

I was looking through my note book of ideas and designs last night and saw an old idea I was going to try inserting into a water heater flue to make a compact tube type Burner.  
If I can play with that idea a bit and learn a bit more as to what that takes, It may be possible to  make up something that slides into the existing fire box and keep the rest as normal.

Other thing might be the Spray burner Roger linked to.
The real trick in that setup is the compact High pressure pump.  I have a nozzle I bought years ago, they are run of the mill but the best thing I could come up with for a High pressure pump was a power steering unit. The other one was an ABS unit but I'm not sure if they pump or just pulse.

Thanks again for your time and trouble Tony. Very kind of you.
 
rogerdw
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I had no idea that's how those things worked Tony, thanks for the education.

What size are the outside air inlet and the exhaust outlet  ...  and I imagine they'd need to be kept pretty short.

I have a couple flueless Rinnai convector heaters from our last place (Rinnai Convector 516TR)  ...  but have never had the covers off  ...  as well as another one, but with the traditional type burner 'tiles' or whatever they are called  ...  with an exposed flame.

I tend to prefer that one because it just provides radiant heat without causing a draught  ...  which I usually feel around my ears. Hate that.  


Dave, if you were to modify a device like this  ...  would you consider a traditional oil heater?

Then all you'd need to do is doctor your fuel to the best consistency for it and away you go. No need to reinvent the wheel.

My aircon mate still services oil heaters and while he doesn't especially like the task  ...  still reckons they are a useful tool  ...  and says old people love them.
Cheers,  Roger
 
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I have an update for today and we had an awesome result  ...  the best we've seen so far I think. Had a temperature gain of 7.4 degrees!!!

Started off with the fan on half speed via my variac  ...  and when I came in for lunch it was sunny and the outlet was pumping around 35 degrees  ...  so wound it up to full speed.

You can see on the chart exactly where that was because the temps dropped 5 degrees pretty much straight away as the extra volume and speed of air pumped it out.

It ran nicely until later in the day when I suddenly remembered it and raced in to have a look. As the outlet was down to 26-27 I dropped the speed to half again (at 16:36)  ...

...  but it only ran another 8 mins before the controller turned it off.

Looking at the graphs, I may have had a better result if I'd reduced the speed around 3 o'clock perhaps.

Regardless, I was rapt with the result.


Cheers,  Roger
 
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  Davo99 said  Don't know what your Connection charges are but having a connection to the grid wouldn't be the worst thing for backup and piece of mind.  Certainly wouldn't be a bad idea at least for a year  while you got sorted and any bugs ironed out.


I'm not sure exactly  ...  but I'm happy to pay just for the peace of mind factor. And if it has an auto changeover  ...  or at least an easy sequence to restore power in case I'm away  ...  all the better.


  Quote   My recommendation would be start with all the solar you can fit in your roof  and then consider a Ground mount setup as well if you need extra for winter.  You can always turn it off in summer or Get a used split AC system and run it in your shed.


Yeah, my thoughts exactly. The shed roof is pretty big  ...  and if I needed ground mount  ...  I could lean a row of panels against the fence, and against the shed wall  ...  all facing north and in the clear with no buildings or trees to create shade.

There's about 60 metres there  ...  so that's a lotta panels. Though somehow I don't think I'll ever use up all that space.  


  Quote  I have not worked out how much power my daughter costs us but in reality, I don't think it's much.


You're probably right and maybe I was being a bit unfair  ...  though the gas bill for hot water has definitely eased up  ...  at least down to half.

Running the pool pump on direct solar has made a huge difference.


  Quote  Well done! That is something.  Something difficult and not to be dismissed lightly either. Changing ones habits be they significant or otherwise is not easy and should not be taken lightly.


Thanks, I needed to drop it drastically coz it wasted so much time  ...  but dropping it altogether has been a big plus. Just hope I don't get sucked back into it.  


  Quote  Offer MORE?? I think that's Illegal! Is in my book of tightarse Scroogeness  anyway!    My father seems to have gone from being horrified to amused how I negotiate and buy things for less. He's even started trying it and had a few good outcomes.


Yeah it's certainly unethical to try and undercut someone else I suppose  ...  but I would have gladly paid $500 for that lot. Everyone else asks at least $1,500 for similar.


  Quote  That is very insightful and helpful. Thank you Roger.  Having an outside perspective
on things is Very important and really the secret to being successful in something.


Thanks. I have no idea if that's how it all works  ...  but reading the comments gives a lot of insight into the viewers and what they seem to be getting out of it.

Clearly there's a lot who resonate with your views on things  ...  and while they might not be game enough to say some of those things themselves  ...  they can get a real kick out of someone who doesn't care what others think and is quite happy to say what they believe  ...  and in such an entertaining way.


  Quote  A client, a world famous Behavioural Scientist as it turned out whom also became a dear friend gave me a heads up early on in doing my Glamour work.  The insight he gave me similar to yours made the world of difference to my success in that field.
I literally can do things and talk to Clients in a way others can't because I understand what they are really wanting where I have yet to come across anyone else that has the same insight.  Of course at first it was a bit difficult but then soon as you see it works and get the feedback, then it's a walk in the park.


That's awesome. We only need a handful of insights or see things from a different angle to really make some progress in life.

I remember one that I picked up years ago related to being shy or lacking confidence in public  ...  and that was that everybody else is walking around just as scared as I am  ...  and realising that has made it relatively easy to go talk to anyone I please, when I am out and about. It was actually life changing.

And I recall only twice out of maybe thousands of times, where the people were not really approachable and it was a bit uncomfortable.


  Quote  I think what you said there is a similar gem of wisdom to keep in mind with this. I will print it out and put it in my ideas book because I think that's a real gem of info there. Thank you.


Wow, thanks. I'm honoured.


  Quote   He said the response he got was huge and now he's at least 50/50 that and his regular subject and the channel has grown faster than ever.


That does make sense. I figure the viewers are there because they resonate and connect with the speaker  ...  and so anything they say or talk about is likely to be of interest to most of them  ...  unless you went from oil burning to crochet perhaps  ...  that might not work  ...  but tree felling and huge logs and machinery  ...  perfect.


  Quote  I have thought for a long time that my subject is pretty limited in advertiser direct appeal or sponsorship opportunities but this would be right on target.... as tiny a target as this is.


That may be true, but you gotta start somewhere and this is certainly a fit. And others may pop out of the woodwork then.


  Quote  If I thought something was crap I'd say so and that would soon end the party.


They'd only have to watch one or two of your videos for their own due diligence to work that out. So if they're trying to sell crap and they send you one to evaluate  ...  well serve them right.


  Quote  I hated it but I cannot deny the good it did me.


Haha, that's exactly how I felt when I used to go, years ago.

I took up running about 7 years ago doing the parkrun every saturday morning  ...  but then hurt my ankle gardening of all things, so was out for 6 months  ...  then covid knocked it on the head and I haven't got back into it since.


  Quote  First would be instead of making the paper mache with water, what about using  Veg oil?


Sounds like a brilliant idea  ...  especially if you could work out how to do it in bulk with wood chips or similar. Then feed in one or two blocks a day instead of a constant stream of wood. Definitely worth looking into.
Cheers,  Roger
 
Davo99
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  rogerdw said  I have an update for today and we had an awesome result  ...  the best we've seen so far I think. Had a temperature gain of 7.4 degrees!!! Once again, very Impressive!


  Quote  Started off with the fan on half speed via my variac  ...  and when I came in for lunch it was sunny and the outlet was pumping around 35 degrees  ...  so wound it up to full speed.

You can see on the chart exactly where that was because the temps dropped 5 degrees pretty much straight away as the extra volume and speed of air pumped it out.


That raises Questions and thoughts with me.
If the airflow was in fact Doubled ( and that may not be the case because I have seen fans and pumps do more than half their volume at  half speed/ Power) it would seem to suggest to me a restriction of some sort.

That would be the capacity of the blower to push air through the passages available and either the fan is flat out and has no more to give or the cumulative back pressure is disproportional. Either way, the tubes are delivering a given amount of heat and if doubling the airflow only causes a Temp drop of 1/6th the half speed, there is something else at play.

I believe it was earlier suggested that with the larger setup the restrictions will be lessened but I'm wondering if the airflow through the tubes will be as well? I tend to think it will be.  That would logically increase the output temps substantially. Whether or not it increases the power output  I think could be another thing.

There would seem to be a sweet spot with the tubes of having the air output around 30.  I don't know if having it higher is leaving  energy on the table  though having the tubes run hotter.

It will be interesting to see in any event.  From observations with different things, they seldom are liner and far more often appear to be exponential.

  Quote  It ran nicely until later in the day when I suddenly remembered it and raced in to have a look. As the outlet was down to 26-27 I dropped the speed to half again (at 16:36)  ...


It seems you need to be able to 2 step, or more, the fan speed automaticaly.
Not sure if Tony thinks a PWM is a good long term idea but if not, maybe a power resistor would do the job on a DPDT relay? At least you could put the resistor in the air flow and reclaim the lost energy going into it.  Wouldn't be hard to run the controllers together so the 2 step did half speed at a certain temp or below and
ramped up if above that.

  Quote  Regardless, I was rapt with the result.


As well you should be. It seems  the significant deciding factor on this is not the season warming up but the sunlight Improving.
This may not ( like my little diesel) be up to providing all your heat especially in the middle of winter but the full unit may be able to provide the lions share going into and coming out of winter and that will make it more than worthwhile in itself.

This is going to be a fantastic asset being how totally hands off it's going to be once setup.  No need to fuel the thing, next to no maintence and no hands on time required. Go away on holidays and the house will still be ventilated and warm and in no danger if something goes wrong.  

That too is significant.
 
Warpspeed
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Great stuff there Roger !

Its interesting that when you increased the fan speed, the air temperatures coming off the tubes dropped significantly, as expected.  But the room temperature continued to climb at about the same rate regardless of the much lower temperature air coming from the tubes.  The full heat flow was still there !

At the moment, at full blower speed there is probably a lot more air than really necessary, but the air volume requirement will increase significantly once the full system is installed.

***

Those radiant gas heaters are much less efficient than the heat exchanger type.  Most of the heat goes up the flue, and although you might feel warm sitting very close to one, the far corners of the room will not heat up anywhere nearly as well.

I used to work at the Gas and Fuel research lab where we tested a lot of different gas appliances. These Rinnai energy saver gas heaters beat anything else by a mile for actual measured heat output.  The flue gas is only just warm, all the heat goes into the room. The radiant heaters use room air for combustion, meaning that there has to be a cold draft somewhere.  The heat exchanger heaters recycle room air, so no cold drafts.

Roger, the flue pipe size is inch and a quarter. Surrounding that is the induction air pipe which is two and a half inches in diameter, but they recommend a three inch hole through the wall for installation.
Its small enough to feed up within a standard stud inner wall.  They recommend no more than three metres of vertical pipe, and I found out the hard way what happens if there is more.

The gas burns cleanly, although there is a very slight amount of very fine ash produced.
If the flue stack is way too tall, the induction air blower is not powerful enough to blast the ash up that high, and about a coffee mug full of ash can it can accumulate at the bottom of the flue, and eventually block the flue.
That becomes a problem after about a year to eighteen months, where you will then need to clean out the ash to prevent the heater from continually shutting down and failing to relight.

Usually the flue just goes straight through an outside wall and is only a foot or less long.
The clever part is, the flue and combustion air always see the exact same air pressure. Even in a storm, with very high winds, the burner is still fed by the combustion air blower and the flame still burns evenly without flicker. It all very clever.

If you look at the last picture in my earlier post, there is a metal plate held by some screws at the lower right hand side of the fire box. The whole gas burner, flame sensor, and ignition electrode slide out all in one piece. It might be viable to fabricate an oil burner that replaces all of that, and use the existing blowers, fire box, and heat exchangers just as they are.

Here is an internet picture of the back of one of these heaters.



The grey convoluted pipe is the suction side of the combustion air blower, the small black pipe at the blower intake measures one side of the differential air pressure directly across the combustion air blower.
If the flue becomes restricted, and air pressure switch halts the ignition sequence.
Flue exit is at the right. The flue pipe swivels and telescopes in length, so its easy to align with the flue fitting fixed to the wall behind. Room air intake and air filter are at the top.

Most are installed against an outside wall with a standard flue kit.



But fitting kits are available for a vertical flue either within a stud wall or through  a wall and then up.

These are great heaters, but sometimes can be troublesome because one or more of the dozen or more sensors go faulty and there are no diagnostics to tell you why the microcontroller spit the dummy.  Often the problem is only a partially blocked flue....

Many people just give up after several expensive service calls by a plumber/gas fitter fails to fix the problem. And then sell the damned thing for peanuts in sheer frustration, which I can well understand.
Edited 2021-08-10 08:41 by Warpspeed
Cheers,  Tony.
 
Davo99
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  rogerdw said  

Dave, if you were to modify a device like this  ...  would you consider a traditional oil heater?


I'd consider any product that was workable and safe... Trouble is I don't think this is workable.

As I understand the heaters you are talking about which I looked at many years ago, they are not compatible with waste oils.
Refined fuels burn without leaving behind deposits.  I call it the tablespoon test. Get some Petrol, diesel, bio, Kero, turps.... You name it, light it off an let it burn. These heaters run on what is un road taxed Diesel.  It's not oil in the sense  we understand the term normally to be. Diesel engines though are often referred to as Oilers though.

Refined/ Commercial fuels and solvents will leave nothing but soot when burnt.  Do the same test with any waste oil and you'll get some deposits. Initially carbon that will burn to fine ash if given enough supplementary heat.  WMO can leave about 5% of the liquid volume as a deposit. Veg less but still there.

As I understand the heaters you are talking about, they are basically a vaporising type setup.  Using a waste oil is going to leave a LOT of deposits and cause the thing to fail unless cleaned out at very regular  (impractical) intervals.

One of the key functions of the burners I design are they are self Cleaning. The generate enough heat to burn all the deposits to fine, wood like ash which is then expelled.  That's different to Draft burners which would be similar to the heaters you are talking about which have no forced combustion air that will build carbon and deposits which need to be cleaned out.

Mine can run Non stop till the things burn through and use 1000L of oil and when you stop them, there will only be a pinch of fine ash, if that  if you shut them down properly.  I have never seen or been able to get a non forced air type to self clean and burn out the Clinker that forms.

  Quote  Then all you'd need to do is doctor your fuel to the best consistency for it and away you go. No need to reinvent the wheel.


They would work with Biodiesel and I believe in the past I have read of people running that in them. The other alternative no one really does is Crack ( Distil) the oil. I have done that and OK if you want a Litre or 5, a lot of work and energy if you want to make Hundreds of litres.  Not something you would walk away from and let run like oil processing and not without inherent risks.

  Quote  My aircon mate still services oil heaters and while he doesn't especially like the task  ...  still reckons they are a useful tool  ...  and says old people love them.


I remember having one in a House I lived in as a Kid. That was a Cold place as well and my brother and I would be Huddled around the thing of a morning before the step bitch would inevitably come in and yell and scream at us for something. I think of the cow every time I see one of those damn things.
I remember it could put out a lot of heat but anything bar the lowest setting got us in the ship for using too much fuel.

My Father loves his wood fire, I think the flames remind him of younger years  with fuel stoves  and I would surmise the oil heaters are of similar effect and comfort to other senior Citz. I think most people would find the look of flames soothing that's why they make those ghastly Faux electric Fires.
 
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That is pretty much what I thought Dave.  Converting one to oil would be way beyond my own knowledge and ability.  

But some of the heat exchanger parts might still be usable somehow. Those small Chinese oil heaters seem to work, and something similar but built to be a bit more reliable and long lasting might be possible ?  I really do not know.
Cheers,  Tony.
 
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  Warpspeed said  Great stuff there Roger !

Its interesting that when you increased the fan speed, the air temperatures coming off the tubes dropped significantly, as expected.  


I read that very differently.  Dropping 5o from 35 at double fan speed or thereabouts  didn't seem much to me at all. I would have expected something much more linear. Is there some equation/ formula for that as to how this acts?

I would think that while there is a given amount of energy in the tubes, the increased airflow had the potential to more efficiently harvest it.  THat may mean lower temps but Higher airflow but I would have thought unless there was something else at play doubling the airflow would have reduced the temps more... unless the blower is maxed out and the tubes can take more Flow.

Interesting stuff none the less.

  Quote  Those radiant gas heaters are much less efficient than the heat exchanger type.  Most of the heat goes up the flue, and although you might feel warm sitting very close to one, the far corners of the room will not heat up anywhere nearly as well.


One thing I always lament when I see DIY heaters  is they appear to have the shortest internal Flue possible. Many people take the flue up a foot or 3 then punch it out a wall.  I remember suggesting to one guy doing an oil burning shed heater to run the thing at a slight angle all the way along the wall before having it exit outside.
He did that and even put a couple of fans down the length blowing along it.
He seemed to get great efficiency out the thing.  It did tend to soot the Chimney but we foresaw that and he put in a very clever way of easily  cleaning the thing  with a port at the end of the Horizontal/ Vertical Junction.  He opened the cap, got a long brush and shoved all the soot back into the  heater and when the dust settled  just  trowelled it out.  The vertical flue he put a bag under the end and got up on the roof and broomed it in and that was it.

  Quote   The flue gas is only just warm, all the heat goes into the room.


I was given another gas heater years ago from a central heating system.  I couldn't figure the thing out. The apparent output appeared to be a PVC fitting.  Asked mate about it and he said that's right, for their energy rating the flue gas has to be 40oC or below. I found that utterly amazing.  The HE on this one was just a bunch of U shaped pipes with an inlet and outlet side much like Rogers Tube setup.
The fact anything combustion could have a 40O flue temps seemed amazing but as the PVC on this old heater was not in anyway deformed and clearly as built confirmed that's what it was doing.


  Quote  The radiant heaters use room air for combustion, meaning that there has to be a cold draft somewhere.  The heat exchanger heaters recycle room air, so no cold drafts.


That's always something I think of with combustion heaters. Also why I set up the diesel  outside to blow in. Rather have some warm air pushing out than the cold air sucking in.  I have wanted to bore a hole next to my fathers wood heater in the floor for years to give it an air inlet to equalise the internal are pressure without sucking cold air in from wherever else.

I was recently looking at those portable AC units. Thought they would be good to have and could run off single phase. Then I read something that said they push the exhaust air out but  draw that air from inside.  How stupid!  If that is indeed the case and they have no inlet, the things must end up being as inefficient as all get out.

  Quote  
The gas burns cleanly, although there is a very slight amount of very fine ash produced.


I never knew that! I though Gas burnt without any ash at all.  Learn something every day! I have seen gas boilers Caked in soot but that was after some sort of failure and why they were being pulled out and replaced.  Never knew gas produced any sort of ash though!



  Quote  Many people just give up after several expensive service calls by a plumber/gas fitter fails to fix the problem. And then sell the damned thing for peanuts in sheer frustration, which I can well understand.


I hope to be able to find such a unit to experiment with.

Reminds me in my younger days when I would drive round when the local council Clean up was on looking for old lawn mowers to do up and sell.  The amount I picked up that took nothing more than a spark plug or clean the carb to get running I lost track of. That was more common than finding ones that were actually stuffed! Very common for just a whisker to be across the plug electrodes shorting them out. " clean" it with a feeler gauge and the thing would fire right up.

I also clearly remember pulling quite a few down early on automatically presuming they would need a rebuild only to find they have been recently been rebuilt with a rebore and everything. After a few like that I checked the plug and then tried starting them before tearing into the things.

Guessed then it was the same thing, Paid a lot to have them rebuilt and then the thing stopped shortly thereafter with a very Minor problem so they gave up on it and Hoiked it.

Wonder how many people bought a new one and then had the very self same insignificant problem?  Quite a few most likely from what I saw.
 
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Haha I have found the exact same thing with lawnmowers. If they won't start, most usual cause is the plug.  

Second most usual cause on a Briggs is the carby. Replace the big single gasket and it will usually then go.  

Third most common cause is the aluminium keyway in the flywheel.
If the mower blades suddenly strike a solid object, the keyway between the crank and flywheel instantly shears.
Its designed to do that.
Once the flywheel has twisted on the crank, the magneto timing will be way off, and it will never start.  Not a chance.

If the valves or rings are stuffed, it will probably still run but be gutless.

Getting back to the natural gas heaters, the amount of very fine light grey or white ash is very small. It will run through one winter just fine if no ash can escape, but start to struggle towards the end of a second winter.  At least that has been my experience with natural gas.  I have no idea about propane, it could very well be ash free.
Cheers,  Tony.
 
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Spoke to my mate in AC today. I asked him what sort of Flow rate an average Ducted system would have? He said around 900l/m or 32 Cuf Min.  I said that was less that I would have expected and he said the idea was to have the air pretty warm but not to feel a draft as that was perceived as cold.

Thought that may relate a bit to the sort of ballpark flows for the tube System.
 
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Thanks for the input guys.  You raise a good point about the airflow between full and half speed.

With the original fan I found that 140V (not 120V) gave half the air velocity  ...  so with this fan I just used 140V for low.

But now that I've checked it  ...  at full speed the air speed is 28.34 ft/s and on 140V is 17.2 ft/s  ...  so maybe I should check it at 120V coz that looks like it may be closer to half.


Anyway, here is todays results. Initially I was surprised  ...  but I likely messed them up because I kept the fire going this morning because my wife was home for the day.

I was weighing up  ...  do I look after my wife and risk messing up my figures  ...  or do I keep my conditions consistant  ...  




Cheers,  Roger
 
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While the wood fire surely contributed to your heat input, you made higher overall gains yesterday  demonstrating that the combustion stove was not entirety responsible  for the gains you saw.

When it comes to happy wife or a day of consistent data, appease they wife every single time .  Doing anything else is certain to get you the cold shoulder and hot water at the same time.
 
rogerdw
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  Davo99 said  Spoke to my mate in AC today. I asked him what sort of Flow rate an average Ducted system would have? He said around 900l/m or 32 Cuf Min.  I said that was less that I would have expected and he said the idea was to have the air pretty warm but not to feel a draft as that was perceived as cold.

Thought that may relate a bit to the sort of ballpark flows for the tube System.


Okay, thanks Dave.

Now that is a long way different to what this jumping castle fan is doing.

A few pages back, Tony wrote  ...

  Quote  28.34 Ft/sec x 0.1726 = 4.89 cubic feet per second = 293 CFM.


So even at the slower speed of 17.2 ft/sec x 0.1726 = 2.968 cubic feet per second = 178 CFM  ...  still 5.5 times more than recommended.


Of course, I assume that 32 CFM is per duct  ...  and most larger size rooms will have at least two outlets  ...  so can we say 64 CFM or even 96 CFM for three outlets?


Dave, I wonder what temperature he calls "pretty warm"? Will it be 10-15 degrees above room temperature like my mate keeps saying  ...  or warmer still?
Cheers,  Roger
 
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Golly, 32CFM is computer fan territory.

I cannot find my anemometer right now, its definitely around here somewhere hiding in plain sight. But when I find it, I will make some flow measurements of my various air conditioners and gas space heaters.

All blow a nice breeze which stirs up the air in the room and spreads the cooling or heating effect very evenly.
Noise is definitely objectionable, but if you are snug and warm and its cold outside, a bit of gentle detectable air movement is not going to be a problem.

You definitely don't want the heat to stratify, so its only warm up near the ceiling, while your feet freeze.
Cheers,  Tony.
 
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