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Bryan1

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Joined: 22/02/2006
Location: Australia
Posts: 1344

Posted: 07:28am 09 Aug 2022

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G'Day Guy's,
Back when we bought the farm we bought a lpg/electric fridge and it worked for a few years then the gas reg clogged up due to dirty house LPG bottles. So this fridge has sat in my shed ever since and i decided time for a bit of fun

I do have 2 off 12 volt batteries from my '06 Subi Outback sitting on my radio circuit which has ran for close to 2 decades using those free nickel iron batteries.I went and bought a 12 volt 600 watt inverter for under $100 bucks and hooked up the fridge to see if it still works. Well the current draw on the batteries is 22.6 amps and only being 45AH starting batteries they didn't last more than an hour before going down to 11 volts.

So I thought well it is fun making burners and my moonshine being at 90% for my neutral as it does need another run to get rid off all taste. Ran it twice now and 3rd time is needed.

So the old gas burner that a weird thread that wasn't standard and a 1/2" pipe OD, so I made a 200mm long chamber out of copper pipe and put a 1/2" hole in one end to hold the burner.

Keeping the liquid level at the right level is the key to burning a nice flame and I did find tilting the rear end up produced a much better flame and I used my separatory funnel to at first deliver a drop every 8 sec's but found i did need to increase the drip rate to about 3 seconds. Now the funnel size is 250ml and I reckon from rate of the drop it will go over night and still be going in the morning.

This is a temp setup to prove it works then I'll make a permanent setup with a drip glass window and needle valve to set the correct flow. If too much is metered it will pour out the burner and cause a fire.

I did find a copper reducer to put over the flame so it could get a good burn and in that picture is an inverted view of the flame with that mirror.

I make my own lager beer so this first test of the fridge is to lage that brew I bottled today.

Cheers Bryan

Davo99
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Joined: 03/06/2019
Location: Australia
Posts: 1578

Posted: 09:50am 09 Aug 2022

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Brilliant!

Would be interesting to see what the consumption is per hour on the booze.
The funnel at 250ml ( looks bigger) would hold about 1.4 KWh of energy.

If the 12V draw is about 286W W, Comparatively the booze should power the thing about 5 Hours.

300W say would not be hard to generate with solar so you should be easy able to power the thing through the day off that. If you kept the thing full with bottles of water filling all the empty space, you would increase the thermal mass and may not need to run it at all at night.

If you did, then the booze should do the trick even if it runs out early morning and only has to wait a few hours for the sun again.

One thing that comes to mind with your dripper arrangement is that as the fuel is consumed, the pressure may drop and the amount of drips you get per second may decrease and the flame may possibly go out.

I mucked around with this constant level thing with printer ink. There are various tanks you can get for that application that maintain a constant level effect but I found that floating bottles in a vessel of water had much the same effect.

As the liquid was used the bottle floated higher and the level was pretty closely maintained.

If you want to do this as a more permanent setup, that may be a simple way of achieving what you want.

Bryan1

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Joined: 22/02/2006
Location: Australia
Posts: 1344

Posted: 02:25am 10 Aug 2022

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Well had a look this morning and the burner had gone out and while I had it apart to try out some air.fuel ratios silly me broke the solder joint on the burn pipe. So cleaned it up and decided mount facing down so the chamber which holds 150ml is facing down at the back. This will cause the fluid level to stay constant and I did shove some SS scrubber up the burn pipe to stop surges of fluid if I over fill it.

Well with this setup the flame is the best yet and in the next few hours see if I can get this ammonia boiling to kick start the fridge.

Edit:

Now for the flow rate and with 20 drips it amounts to 0.5ml and just now it took 45 seconds to do the 20. I have the chamber full and with the drip rate getting a slight over flow which improves the burn size by a huge factor and finally the fridge is starting up just off the moonshine

Cheers Bryan
Edited 2022-08-10 14:13 by Bryan1

Bryan1

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Joined: 22/02/2006
Location: Australia
Posts: 1344

Posted: 06:40am 10 Aug 2022

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Update,
Got the 20 drip flow rate down to 30 seconds and by over driving the burner I worked out about 1ml minute so around 1.4 litres a day

The freezer is now down to -3 degrees and the fridge down to 6 degrees so the goal is too see if this will go all night.

I'm making up a new permanent drip fixture and I'll use a fuel tap off a RC car and use some 1/8" teflon hose. The main hopper is a 2 litre goon bottle and I drilled a 10mm hole in and I had a rubber grommet and for a solid mount epoxied the joint.

Cheers Bryan

Bryan1

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Joined: 22/02/2006
Location: Australia
Posts: 1344

Posted: 09:04am 10 Aug 2022

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G'day Guy's,

YAY got the fridge working nicely now and setup an overnight solution

It was fun connecting the RC fuel throttle and I found on one section it was only 2.5mm so got some 1/8" copper tube and screwed it into the tube and cut a silicon washer so the nut could press on it to ensure a seal.

Now getting the burner to just over run proved what was needed to kick start the fridge

and the best part

So it will be interesting to see with the new drip arrangement if it stays going over night and the level left in the 2 litre bottle.

Cheers Bryan

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