The pilot light stays lit and the main burner has relit 2 times for a few minutes. I don’t know makes the diaphram open to let gas to the burner, but that seems to be my problem. Thank You for replying. Michael
Sure sounds to me like you have a problem with a faulty thermostat on this heater which for some reason is sticking and not allowing the valve that allows the gas to flow to open and close properly. I would suggest you look at the thermostat and it’s likely replacement to resolve your problem. If the heater has a Robertshaw RT control valve then it is very likely that the poppet valve seat is sticking and you should get a suitably qualified serviceperson to attend to it freeing up ( which usually involved cleaning the valve seat and the guide ).
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