Question about Hayward H400idpl2 400,000 Btu Low Nox Heater Propane

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Makes a loud bang when starting

The heater makes a loud bang when trying to start and it may do this one or two times and then start. we have lots of wasps could they have built a nest? the heater acts as if a pocket of gas may build up could the heating tube have a crack in it? thank you--- john

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You will need to pull your tray from the heater to check for Wasp nests or other problems. You need to be careful with the wasps if you smoke them out be very careful not to burn any wires or components on the heater. If you have access to a co2 fire extinguisher the cold and lack of oxigen will hold them at bay for a few minutes. Back to the heater...
Your dead on about the gas build up. This comes from something blocking your pilot so that your burner flame isn't lighting on the burner that is connected to the pilot. If you have a wasp nest on the burner this will do be the problem. I want to think that when the heater fires this would fix that problem. What is more common is on the gas pipe that feeds the burners you have a gas orface for each burner. Small spiders will sometimes build webs that resemble lint inside the orfaces. You can clean these with a bent wire.Other than that anything blocking the burners will be evedent. I hope this helps, good luck.

Posted on Dec 10, 2009


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