I think I Need C-wire adapter install help

I have a Goodman heat pump (PHKJ024-`1) and I’m trying to install the wyze thermostat. It tells me I need to install the c-wire adapter, but when I open the unit, It doesn’t look like the conectors where the thermostat wires are connected have any labels. Also is it normal for the Y and W wires from the Thermostat to be connected to the same place on the heat pump?
So on the old thermostat I have:
Red wire connected to RH
White wire connected to W
Yellow wire connected to Y
Blue wire connected to O
and Green wire connected to G

on the heat pump, there are no labels on the connectors. the red wire from the thermostat connects to a fat red wire, green to green, blue to orange, yellow and white to yellow.

how do I connect the c wire adapter?

Can you share a picture that’s less zoomed in please, I need to see more of the wires. Also look for a schematic somewhere.

Also a picture of the current thermostat hoookup would be awesome.
what’s on this piece of paper?


I think I see a way you can wire it that wont need the C-adapter, but would like to see the rest of that paper and the current thermostat wiring to be sure.


Oh wow, Thanks for the quick response. I didn’t notice that paper, mainly because it was getting dark when I took the photo. The unit is on top of the house and it’s a bit late to be climbing up there in the dark. I’ll respond in the morning with a photo of the paper.
I’m hoping it will let me link in this photo of the connections at the thermostat.
I got a message earlier that new users can only link in one image.

btw, on the thermostat the labels say;
RH - Red
W - White
Y - Yellow
O - Blue
G - Green


ok, used the model number to pull up a wiring schematic.

So, as you do not currently have anything hooked up to the W terminals on the heat pump. you probably don’t have the optional electric backup heat.
Therefore. with the power off, you can untwist the white and yellow wires that are connected there and just connect the white wire to the blue (C) terminal and reconnect the yellow wire to the yellow terminal, and also fix the red wire so that it is properly captured under the red terminal screw. All of the wires should look like that green wire, with a loop of wire under the screw. This keeps them from shorting out against any of the other terminals.

At the thermostat, connect the red wire to Rc, the green wire to G, the blue wire to O/B, the yellow wire to Y, and the white wire to C. Then during thermostat setup, tell the wyze app that your old thermostat has the following wires: Rc, G, C, Y, O.

Do not turn on power to the heat pump until the app tells you to.


Not sure what happened. I thought I already replied to this but thanks so much. it’s working great now.


I also have a Goodman heatpump (GPH model) which has the same wiring table in the manual as the one @speadie posted above. My challenge is if I trace the wires from the thermostat to the unit, they do not all connect to the board.

Wires connect in the original thermostat are as follows:
Blue wire connected to W
Green connected to G
White connected to W2
Yellow connected to Y
Red connected to R

In the Goodman Unit:
Blue wire is connected to an orange wire which connects to O on the board
Green wire connects to an aqua/green wire which connects to the fan
White wire connects to a white wire which connects to W on the board
Yellow wire connects to yellow wire and unknown where it connects-runs through a hole on the aluminum wall where the board is mounted.
Red wires connects to a red wire which connects to a transformer.

Trying to determine if I can use a smart thermostat via the c wire adaptor. Thanks for any and all replies!

Pictures of the heat pump unit please - and you’ll need to show the Y wire… do any other wires go out of the same hole the Y wire goes out of?

Sorry for the delay @speadie
Attached is a pic of the unit and the Y wire. And there are several others as shown which go through that hole with the Yellow wire. Can provide more pics if needed and thanks!

And here is the unit…have several other pics if needed

Do you have a picture that shows the wires that go to the thermostat from the heat pump? (inside the heat pump, that is)

I sure do…see below.

This is probably C. where does it go?

Limited to 1 pic upload so grouped a few pics to show the path. Coming from the wire nut it looks to go to some sort of relay/junction box–>transformer–>‘C’ connector on main board.

yes, then it’s definitely C.
hook your C adapter up as follows:

During setup, tell the wyze you have the following wires and it will set itself up for the C adapter:

O/B, Rc, W1, Y1, G

Remember that the Green wire at the thermostat needs to connect to C on the wyze thermostat and G on the C adapter.

Thank you @speadie !!

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