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Hi there,
I have a question regarding a gasfired Rheems 135 ltr HWC. Burner and pilot are not staying on, maybe running at max for a few hours then out. I noticed some water vapor dripping down onto burner and pilot during operation and was curious regarding condensate and combustion? Is this to do with incomplete combustion and the thermocouple? Or how often do gasfired HWCs split? Thanks for you help! John. ;)
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There will be condesate as the cylinder is heating up.Natural gas 10% water vapour and LP gas 25% water vapour.If the pilot is not holding or only holds for awhile it might need replacing
also pilot might have dust on it making flame yellow
- uni-control could be failing- how old is cylinder
Get a Gas Fitter to look at it as you need it looked at safely
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What Daniel said, sounds too me like the ECO in the Unitrol failing, you should aim to have your gas system checked once a year by a licensed gasfitter. That way he can check combustion on all appliances, make sure everything's running correctly and test the system for soundness. If the cylinder had sprung a leak, you would definitely notice continuous water flowing out of it, Even if only a small amount. They always condensate quite a bit upon firing the burner. 8)
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Sounds like the Thermocouple needs replacing. Rheem still sell them as very common issue.
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Its highly possible.....which should all be checked at the 1 year service ;)
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But then again most plumbers I talk too immediatly suggest the thermocouple for every gas problem hahaha
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When you get your Gasfitter out to investigate, get him to double check the mains GMS regulator (natural gas) Coming up winter time an old regulator can stick and fail under heavier loading couple with colder temps.
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Very true dragon :)
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so its the thermocouple in the GMS that needs replacing... :P...
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just replace the whole HWC ::)
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hahaha no its the manometer that needs replacing 8)
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What i say may not be the issue, but on top of the cylinder there should be a draft diverter, that needs to remain clear at all times, so many people put their clothes around it to dry them off, the effect of that is the products of combustion dont leave the flue to atmosphere and in some cases where downdraft occurs can snuff out the pilot due to lack of air for combustion;
The thermocouple is the usual fault and they are cheap as chips to buy and simple to fit, but in doing so one might aswell as part of a routine clean/check the pilot injector, after assembling and checking for leaks on any pipes undone,ie. the burner and the pilot tubes light it up and adjust the pilot length if it is bigger than a bic lighter flame its more than likely impinging itself on the thermocouple, again upsetting things, all very simple stuff, your main burner should come on and stay on till the water reaches temperature then the burner turns off leaving only the pilot going, just to clarify the burner doesnt go all day its whats refered to as snap-acting not modulating like more complex appliances.