Have a 50-year-old (?) natural gas wall heater in my apartment. Thermostat is
connected to gas valve in heater by 2 wires. No evidence of transformer or
low voltage (ie, 30 vac) on the wires.
Symptom is that the 'stat won't open the valve. If I short the terminals for
just a second, the valve opens, and shuts at the appropriate temperature. (I
since have read that it's not a good idea to short those terminals together;
it could damage the valve, or some other component.)
What replacement thermostat should I be looking for? All I see are multi-wire
types that require a transformer voltage. Will any mercury-bulb type work?
(That's what the old one was.)
I'm also curious where the voltage comes from to operate the valve. Is this
generated by the thermocouple / sensor next to the pilot flame?
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.
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