Thermostat - 2nd stage not working

Either I’m not understanding what I have or possibly the previous installer cheaped out.

Here is the wiring of the old thermostat:

Note the black and white wires on Aux/E (I have heat pump unit outside)

(Limited to one picture per post so I’ll add air handler diagram + wyze wiring in replies)

When I run through the self test, I get heat on stage 1, nothing on stage 2. I do have a heat pump, I do not have a heat pack/emergency heat. I suspect I have two stage based on wires available and the circuit diagram.

Background: As part of the deal to buy the house, they replace the HVAC units. I think they saved a buck by not replacing the thermostat, thus black and white were both connected to W1. Based on this theory and the fact that the thermostat’s terminals do not support more than one wire I put black in W2.

I’m looking at the manufacturer’s installation PDF ( https://www.lennox.com/lib/legacy-res/pdfs/installation_maintenance/lennox_cbx25_iom.pdf ) and that’s making it worse because from what I think I have, cooling with heat pump, is not described there.

Any help would be much appreciated, thanks in advance! :slight_smile:

Wyze wiring:

Air handler diagram:

Yes, the wyze does not appear to run both W2 and W1 at the same time, so you will not get the effect you are looking for. It will turn off W1 when it turns on W2. Hopefully they get this fixed, and allow them both to come on with an advanced setting in the future.
Your cooling and heatpump are taken care of by your compressor, condenser, and evaporator, that’s the diagram for the air handler and heatstrips, which is why it doesn’t show any of the cooling components.

3 Likes

I am awaiting firmware update to energize both terminal W1 and W2 to get my Stage 2 heating to activate and operate properly, for now the furnace is handling Stage 2 after 12 min of Stage 1 and is considering the thermostat as a single stage.

1 Like

Hmmm. Thank you all. I guess I better open a support ticket just in case I have to return it.

I also have second stage heat not working @speadie.
I’ve got a heat pump system with electric auxiliary heat.
Testing shows
cooling works
stage 1 heating works.
stage 2 does not turn on auxiliary heating.

Here is the original wiring

Google Photos

Here is what Wyze directed
click on image to make larger.

Google Photos

What kind of heat did you select for the W1 terminal? You probably want to select electric, if you have a heat pump.

Yes, electric was set during setup.
Apart from auxillary heat not turning on during stage 2. The App didnt enable an emergency heat function.