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We have a Gourmet slow combustion stove that heats our water in winter. The problem we have is that we quite often get air locks in the system and the hot water is reduced to a trickle until you find the tap that allows the air lock to clear. The system is gravity fed. Can anyone tell me what we can do to get rid of the air locks?
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 07:14pm 29 Aug 2010
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dpollod
If possible, tie all the hot operatives (faucets) together using tees and connect them all together with a pump on the system. This will provide a return pathway as well as equalize the feed pressures. Be sure to put a check valve between the hot side and the feed side, so cold water doesn't take the path or least resistance giving you a shot if ice water while you're showering.
Where is the "air" coming from? Are you sure there's not something in the system "gassing" like zinc or magnesium producing hydrogen with a stray current from something like cheap stereo gear using a floating ground? If the system is under any pressure at all, air can't enter unless coming from within or from an outside source at a higher pressure than the water in the system.
. . . . . MacEdited by MacGyver 2010-08-31Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
Robb Senior Member Joined: 01/08/2007 Location: AustraliaPosts: 221
Posted: 12:26am 30 Aug 2010
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Most likely not a pressurised system. I get air locks on mine too. Its something like this:
I'm sure a higher head tank would fix it but its one of those things that need a 'round toit'
With stubborn airs locks I take the washer assembly out of the last tap and give it a blast of compressed air till it bubbles back into the tank.
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 01:54am 30 Aug 2010
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dpollod
Where is the air getting into the system in the first place? Is it flowing backwards from the point of use when you open a tap?
One solution might be to add a water pump that delivers its payload into a closed tank about half-filled with air. That cushion of air will compress and deliver its pressure back to the water when there is a demand for use. The tank has a pipe coming through its top then traveling inside to just above the bottom of the tank inside where it is bias-cut (angled). Inlet water gets pumped through this pipe against the pocket of air. When the pressure goes to zero, there's still water in the tank, so the air charge never escapes.
The motor attached to the water pump is controlled by pressure switches, which switch it "on" and "off" depending on the water-pressure switch settings. It's a no-brainer, really.
These are called "Pressure-Assist" systems and are available at most box stores (home-improvement stores).
Hope that helps. Just to let you know I'm not making this up as I go, I'm a licensed plumbing contractor, retiring from the trade in May of next year.
. . . . . MacEdited by MacGyver 2010-08-31Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
Jarbar Senior Member Joined: 03/02/2008 Location: AustraliaPosts: 224
Posted: 09:37am 30 Aug 2010
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dpollard,
My hot water stops running because of an air lock caused by water leaving tank faster than header tank/ball valve can fill it up.Usually when running a bath which is a fairly rare event around here.The bath has a tee type mixer where both hot and cold are combined before leaving spout.
If an airlock develops and the spout is not roasting hot,I place my thumb over the spout and open the hot valve all the way.Still holding thumb over spout I then carefully crack open the cold valve.The cold water will find its way around the valve seat in the hot tap and fairly rapidly (30 sec) back fill the hot pipe,air can be heard purging into header tank.
Turn off cold and remove thumb and away your hot water will run again.Just don't turn cold on to fast or hot water valve seat closes and you get a wet face.If this occurs just go back to the start of process and repeat cracking open cold more gently.
Anthony.
"Creativity is detirmined by the way you hold your tounge".My Father
"Your generation will have to correct the problems made by mine".My Grandfather.
GreenD88 Senior Member Joined: 19/05/2009 Location: United StatesPosts: 104
Posted: 12:13am 31 Aug 2010
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If your getting air in the system then your header tank and pipes are all running empty. Like Mac said you could install a pump which would help push the air lock through the pipes. Or you could install a solenoid and float to keep the tank from running dry in the first place. Is your cold water pressurized or gravity too?Licensed Master Plumber / EPA 608 Universal License / 410a Safety Certified / Medical Gas Brazer/Installer
Robb Senior Member Joined: 01/08/2007 Location: AustraliaPosts: 221
Posted: 05:23am 31 Aug 2010
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If you boil a shepherd's crook tank system you will soon find out how the air gets in You get water, steam and air shooting out the tap and the pipe on the roof Edited by Robb 2010-09-01
Thank you all for your suggestions. I think most of our problem is that our water is from tanks and is all gravity fed, no pumps other than to pump from our collection tank up to the two that feed the house.
We may have to live with the air locks when they occur. We only use the slow combustion stove to heat the water in winter and in summer go back to off peak electricity.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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You get water, steam and air shooting out the tap and the pipe on the roof