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I have a Cozy one-sided gas wall heater. It is no longer lighting the burners when the wall thermostat reaches the temperature set point. The thermostat will "click" on, but the burners won't ignite in the heater. This has been an intermittent problem, but is growing steadily more frequent by the day. Sometimes when the burners won't ignite, I'll bang on the heater and then they ignite. But even that "temporary fix" is becoming less effective. What part on the wall heater needs to be replaced or serviced so that the burners light when the wall thermostat sends out its signal? A new wall thermostat was installed about a month ago because the same problem was happening with it, so I know it's not the thermostat.

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Can you remove the front cover to the wall unit? Look for the wiring and follow it till you see a round about the size of a fifty cent piece. Should have 3 of them. One of them is not closing and allowing the signal to go through. So turn up the t-stat to call for heat take each one of the limit switches and by pass them one by one till you find the one that is bad. Depending on where you hit the cover is where I would look first. The limit's are rated by temperature so replace with correct size. You should be able to see the temp. on the limit something like 180 is what you are looking for. Also make sure the wires are in good shape where they connect to the switches. Might have a loose connection. ken

Posted on Jan 03, 2009

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On the control board there is a potentiometer marked "MIN GAS RATE" this needs to be tweaked clockwise until the burner remains lit when the nominal 60-65C duct temperature is reached. Don't turn it up too far or the heater may not throttle back enough and end up going out on overheat.

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Depending on system design, installation and current operating conditions, the time delay from main burners on to fan on can be up to a couple of minutes.

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1 Answer

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It is possible that it may happen again. I reccomend having the burners and burner compartment cleaned, including the Heat exchanger.

If you dont, mind, please rate this solution. All the others were clarificatin requests so we could be sure we found the problem. Now that we found it, It would be great if you could rate the service.

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