Thermostat wiring - not powering on

I just bought my condo this summer and have a very old boiler (37 years and counting… part of the reason I wanted Wyze was to monitor output and have a better sense of when it was dying). I hooked up the wires:

Rh - Rc
W - W1
C - C

And it didn’t power on. There was a connecting wire from Rc to Rh on the original thermostat, but dropped it per instructions. I also noticed there’s a wire splice from my furnace to my thermostat so I’m hoping that is not messing up the wiring too much. Any suggestions would be helpful. So far I’ve just gotten a “rewire it” which I would like to not do if possible.


Cloth wrapped wire is really old. Can you take a picture of the furnace side of the wires?

Like I said … a really old boiler.

That’s an aquastat, you will need an external transformer to power the wyze, there is not enough power available from the transformer in an aquastat to run a wifi thermostat.
Connect a 24V AC wall thermostat adapter to Rc and C and connect the Wire that is currently connected to R to Rh, and the wire that is currently connected to W to W1 on the wyze.
If you have already started to setup the wyze, you will need to either restart from the beginning, or add a new thermostat, and ignore the partially setup one, depending on how far you got. Tell it you have the following wires during setup: Rc, C, Rh, W. You will not need the wire that is currently connected to C, put a wirenut on it to cap it off, and wrap it in electrical tape to prevent it from shorting against anything else.