Hi,
Tropic Isle Heater 120,000 BTU, Honeywell Gas valve, 3 cast iron burners. No mains electricity supply to the heater-operates from minivolts generated by the Pilot generator. Starite electric pump.
I posted earlier about burners not firing up. I bought and fitted a new Pilot generator and cleaned up the burners which were full of rust. Now, when I push in the pilot control knob, I can hear loud hissing of gas through the main burners. When I turn the heater on with the heater switch and the water pump on, they now fire up OK. But when I switch the heater off, gas continues to flow through the main burner jets and the jets stay lit (small flames out of the main jets, not from the burners themselves.)

If I turn the pump off with the heater on, the main burners shut down but I can still hear the gas hissing through the main burner jets and the small flames at the jets remain.

I didn't do anything else apart from disconnect the heater, replace the pilot generator and then reconnect the wires. I labled all the wires so they went back to the same connections. Why would a new Pilot generator cause the gas to flow to the burners when only pilot light on?

Peter

It sounds like a bad gas valve to me, it is not closing all the way, a small amount of gas is getting through when the valve closes, replace it right away.

As to the Why is it happening now, replacing the Pilot generator enables gas to get into the main part of the valve, where the gas goes out to the burners. With a bad Pilot generator or the pilot out the safety part of the valve closes so gas won't flow at all to prevent disaster.

Jeff