I have a Williams CLB-105 oil furnace with a single-speed belt-drive blower and heat-only service.
I want to use the "fan only" setting on the mechanical LUX T10-1143SA thermostat.
To do this I removed the 18/2 and ran a new 18/5 wire from the thermostat to the furnace and am installing a new fan relay (WR 90-370).
At the thermostat I put a jumper between RH and RC to power the green wire in the "fan-only" mode.
I connected the white wire to "W" and the green wire to "G" and the red wire to "RH".
At the furnace is a Honeywell R7184B oil primary control. The red wire is connected to "T3" and the white wire to "T". There isn't any W, G, Y, or R connections, only a 1 and 2 that go to a "enviracom" system.
At the new relay I connected the green wire to one side of the 24v coil. I can't find the common side of the 24v transformed to connect to the other side of the relay coil. Does anyone know where its located and how I can connect to it?