I was working on a fireplace that has an issue with the pilot going out mostly when the main burner is on. The system has a robertshaw mv gas valve, and thermopile. No spark ignition,or external power source. The gas valve, and thermopile are brand new, the pilot was cleaned, and the batteries in the remote, and receiver are good. The open circuit voltage of the thermopile after one minute of holding the knob down is 625 mv. The closed circuit voltage with just the pilot on is 425 mv. When the main burner is on the closed circuit voltage drops to 160 mv, and stays there. Sometimes the fireplace stays on for four or five hours without the pilot going out, sometimes it is on for only twenty minutes. The closed circuit voltage is the same if the remote is in the circuit, or those wires are removed from the valve and a jumper is installed across those terminals on the valve to open it. The pilot flame is the same weather the pilot, or main burner is on, it envelopes the top 1/2" of the thermopile. Adjusting the pilot valve screw has had no effect on the condition, and the incoming gas pressure is 6" w.c. I am looking for suggestions on why with a brand new valve, and thermopile the closed circuit voltage drops so drastically when it is attached to the valve, and the main burner is on. Happy holidays, and thanks to all.
↧