zhrinze
Dec 12, 2006, 03:27 PM
I have a gas fired boiler for a radiant (water radiators) system. I know the following:
1. It has a V15-5 gas valve
2. It has a very dysfunctional TM850A Honeywell Thermostat (it's very old, but I have the installation manual)
3. It has a L170A Aquastat (the wires pass through)
4. I have a wiring diagram and blueprints for the entire system. It was installed by the original owner, a plumber. He's dead and his company doesn't know the system, except to say it's more efficient than a newer system.
The heat works well, but the thermostat makes the system run at odd times. I wanted to replace the thermostat with a programmable thermostat. Never having dealt with an old system like this, I just bought a Lux TX500b.
It has connections for G,Y,W,RH,RC. As I understand it, the RH is power from the transformer. The W would act for the gas valve. But my old thermostat also has a B wire and I don't know where to put it.
Any help you can provide would be appreciated.
1. It has a V15-5 gas valve
2. It has a very dysfunctional TM850A Honeywell Thermostat (it's very old, but I have the installation manual)
3. It has a L170A Aquastat (the wires pass through)
4. I have a wiring diagram and blueprints for the entire system. It was installed by the original owner, a plumber. He's dead and his company doesn't know the system, except to say it's more efficient than a newer system.
The heat works well, but the thermostat makes the system run at odd times. I wanted to replace the thermostat with a programmable thermostat. Never having dealt with an old system like this, I just bought a Lux TX500b.
It has connections for G,Y,W,RH,RC. As I understand it, the RH is power from the transformer. The W would act for the gas valve. But my old thermostat also has a B wire and I don't know where to put it.
Any help you can provide would be appreciated.