2 lugs on boiler control, one I'll call "red" or "R" that comes from the built-in transformer with ~14v and one I'll call "white" or "W" which, when jumpered to R, turns on the boiler. Very typical old system, except weird voltage (maybe?)
transformer nearby powering doorbells that reads ~20-22amps from either lug
old thermostat with 2 wires, red and white.
What I've tried: - run new wire (I'll call "common" or "C") from doorbell transformer to thermostat location.
connect R from boiler to Rh on thermostat, W from boiler to W1 on thermostat, C from doorbell transformer to C on thermostat. NO POWER UP of thermostat
connect R from boiler to Rc on thermostat, W from boiler to W1 on thermostat, C from doorbell transformer to C on thermostat. NO POWER UP of thermostat
I am going to buy a 24v transformer locally and try the same as above swapping it for the doorbell transformer (which is cryptically marked, but may be 16v, since apparently that is a common voltage with doorbells).
My concern is that if the idea is that the 24v transformer is simply serving as the common, the 14v coming from the R lug on the boiler is not enough power to power the ecobee. On the other hand, I could:
run both wires from the separate transformer to the ecobee call them "R from separate transformer" and "C"
connect R from separate transformer to Rh on thermostat, connect W to W1 on thermostat, and C from separate transformer to C on thermostat
The concern I have is that the boiler W lug is currently only getting 14v from its own transformer when the thermostat turns on, would upping that to 24v from the external transformer be a problem?
This feels like a weird issue where my boiler switch requires one voltage and the thermostat requires a different voltage. Is it possible that the boiler's internal transformer is just old and weak? That using a new 24v transformer to signal the boiler to start would be ok?
Hope I've explained clearly. I can take and add pictures if needed.
edit: I've sifted through many similar questions, but couldn't figure out if this particular question had already been answered