I ran a 24 v transformer to the R and C wires (per uncle mike). Nothing lights up. Should it? Or do I have to run the Nest Ap before the face will glow in the dark?
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Which exact model Nest do you have?
Does it need some batteries?
It is the Nest Thermostat E. Some online sites say it is self powered and doesn't need an external power source, but they aren't really clear how this is done.
The Nest E seems to have an internal Lithium Ion battery.
Do you have a voltmeter to verify that the voltage is at the end of the wires where they attach to the thermostat? Did you strip the wires before inserting them into the Nest Thermostat?
The online installation manual I found on amazon says you interface by rotating the display and pressing down. do these actions have any results?
The way this or other Nest thermostats would work without the common connected is to use some of the current provided as the heating request signal to operate and charge the battery. In other words, would use the furnace as a way to get to the other side of the transformer. There can be issues with this method.
I switched wire leads from the transformer and the nest lit up. They weren't labled on the the transformer so I thought it didn't make a difference.
Uncle Mike: In another post you said: the W terminal of the thermostat is set to provide voltage when the thermostat calls for heat. You would want to connect it to the TH terminal of the gas valve, while the TR terminal of the gas valve needs to be wired to the common terminal of the transformer. (which also remains connected to the thermostat R terminal(screw).
This means I would have two wires connected to the transformer then? One from the Nest and the other from TR? Incidently there is small wire already conncected to the TR that runs somewhere? What would that normally be?
The heater TR is the common, which connects to the common screw of the transformer. this also connects to the NEST Thermostat C terminal, You can run the common wire between the three devices together in any order.
The transformer 24 volt terminal should only go to the nest thermostat R terminal.
the Nest thermostat W terminal is only connected to the TH.
If you purchased the heater used, the existing wire on the TR may be from the previous connection.
Are you the same person who posted as user kyrral?
I am Kyrral. I think name alters depending which computer I use.
Did you ever get the pilot working reliably? (and turning off the gas when the flame goes out)
I leave it on constantly. It took about half an hour for another person to light so I don't want to risk turning it off and not being able to relight.
I thought you said in another thread that the thermocouple fell apart.
It is my understanding that the purpose of such a thermocouple is as a safety feature, that turns off the gas to the pilot light should the flame go out.
If you could replace the thermocouple with a suitable replacement part, you might have an easier time lighting the pilot light, and be protected from buildup of flammable gas should the pilot light be blown out for some reason.