Wyze thermostat and boiler setup

Just purchased the thermostat and my old thermo has the 4 wire and I need to use the CWA or run a C wire. There are 2 wires at my thermstat (yellow and blue) that are unused and I can find then in the boiler but do not know where to hook up to make a C wire. I also do not know where to hook up the CWA as none of the examples out there are helpful. If anybody can help would be great

That’s a valve… where’s the transformer?

I’m going to assume it’s this but I have never dealt with a boiler system so I know nothing about them. This is inside the boiler unit.

Might want to get a Common Maker from https://www.fast-stat.com/

The Wyze thermostat comes with a c wire adapter if needed. I just was not sure where to hook it up at

yep, that’s the transformer. can i get a better angle ? need to be able to read the letters imprinted in the cardboard

That’s about as good as a picture as I could get, but I found the other pic on the inside cover don’t know if it helps

Do you have a picture of the old thermostat? and how far apart is the valve from the transformer?

You’re going to need to add another wire that runs between the valve and the boiler. The valve is currently wired opposite of how you will need it to be, instead of the red wire being split by the valve, you will need to have the white wire be split, and the red wire in the wirenut.

I’m not sure why the endswitch is hooked up to the thermostat yellow and blue wires, your boiler doesn’t use the endswitch, and if those wires aren’t connected to anything on the other side, they’re effectively doing nothing. This means we can repurpose the blue wire as a C wire with an additional wire nut and wire that connects it to the C terminal on the transformer if the white wire is the one driving the valve.

The transformer is of the older more fragile style, so you will need to be gentle when tightening the screws, and label all the wire that are on each of the terminals so that you can easily tell where each one goes. also, be sure the power is off to the boiler before you start, there isn’t a fuse on this style and you really don’t want to short circuit it.

final hookup would look something like this:

Note there are many more wires on the transformer, and most of them need to stay where they are, you only want to add a new C wire to the C terminal that hooks to the blue wire at the valve.
The valve is currently set up to be interrupting the R wire, which is not what you want, if it is hooked up this way, then the valve will try to open constantly, so you need to reverse it so that it is hooked up across the white wire instead. The yellow wire is unused.

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At the thermostat there is a blue and yellow wire that are unused and end up by on of the valves

This is one of the valves

This is the other

Can I just run the blue wire down to the transformer to the C?

There is a blue and yellow wire at the thermo that run to one of the valves, can i just extend one of the wires down the transformer and hook it up to the C

How many valves (zones) do you have?
and do you have a zone controller somewhere?
It appears your system is significantly more complex than the images shown initially led me to believe,.

You have a separate cooling system, and multiple heating zones. You’ll probably want an actual in person tech to install and wire your smart thermostat.

I’m going on vacation and will be away for a few weeks, but if you still need help I can attempt to assist you when I get back.