Setting the stage - I installed my thermostat last December to my 20 year Lennox A/C and propane furnace (both single stage) and utilized the C wire adapter and all worked well (once we got the firmware to let the furnace manage the blower on heat). Then this past summer the A/C gave up and I had a Heil system installed. A/C and Furnace both two stage. The installer pulls all new wires and hooks up the A/C. The self test it can’t detect the W2 wire but it seems to work. Now he comes back and hooks up the furnace (getting cold in IA). Reset thermostat and delete from App. Add it back and still fails with W2 detection. Self test runs fine on First Stage of A/C and furnace but both turn off on second stage self test. Installer insists everything is wired up ok. When I setup the thermostat I selected propane and forced air for both settings. I am attaching pictures of the wiring for reference. Any help is appreciated.
The wyze doesn’t work as expected with 2 stage heat - most furnaces expect it to leave stage 1 running when it turns on stage 2, but for some reason, wyze’s engineers/programmers made it so that it turns off stage 1 when it turns on stage 2. This confuses most furnaces, so I just have mine set to allow the furnace to make the decision to switch to stage 2. This is done with dip switches, you will need your furnace manual to figure out how to set them.
For cooling, you don’t appear to actually have 2 stage cooling, your compressor run only has 2 wires (Y1 and C), You might just have a separate fan tap (higher indoor blower fan speed) for second stage, there doesn’t appear to be any increased cooling capacity on the second stage.
Thanks for the information. I am obviously not an HVAC person but it has a Y1 and Y2. I thought that was the two stages.
Y1 (yellow wire) has a tap on the furnace board that goes to the compressor (the red wire), but Y2 ( the blue wire) goes to a fan tap on the board, and does not have another wire driving the compressor- I’m not sure how the wyze’s logic works with dual stage cooling, if it leaves Y1 running when Y2 in energized or if it de-energizes Y1 when Y2 is called. As long as it runs properly, it doesn’t matter, but if cooling drops out when it tries to call for Y2, you’d want to put in a jumper from Y2 to Y1, or make the adjustment on the board.
For your heating issue, do you know what board you have or what the model of your furnace is?
Its a Heil G96VTN QuietComfort® 96 Gas Furnace
https://www.heil-hvac.com/en/us/products/gas-furnaces/quietcomfort-96-gas-furnace/
You’ll want to have your wyze set up for single stage heat, then switch the marked switch the other direction (switch bank 1, switch 2)
This will let your furnace control the staging, instead of wyze’s not working implementation of 2 stage.
MANY thanks. By setting up thermostat as a single stage, I assume that means resetting and deleting it from the app and selecting only a Y1 and W1 wires (no Y2 or W2)? Is there anything similar that need to do the A/C? Again, MANY thanks
This only changes the heat setting, so disconnect W2. You can leave Y2 connected to get the increased fan speed for increased cooling. And yes, you will need to reset your wyze.
Speadie, many thanks. I found the furnace control board documentation and flipped the switch you indicated. I also found a jumper that needed reinserted to perform a similar function for the A/C (allowing controller to manage staging). I did a reset in the thermostat and deleted/re-added it backing into the app as a single stage LP and forced air. The controller should handle everything now.
I did open a ticket to WYZE for this. Their third tier support said it should work as long as the same heat type (LP and forced air) were selected for both stages. I assured them I had done it several times and the second stage of Heat nor A/C would work with this thermostat. They asked me to reverse everything, test again and send them logs. I declined and asked them to close the ticket, as this is a well documented unresolved issue on the forums and I had little faith in a resolution. Essentially I trust Speadies experience more than supports.
I have found an Ecobee 4 for $100 on FB MP, would it be worthwhile to get a true two stage thermostat or just keep the WYZE and let the Heil controller manage my single stage.
Thanks - Allen
I have personally confirmed that as of 9/28/2023 with the latest firmware the Y wire remains connected when the second stage of heat is called for on the W1 wire. This should make second stage heat system using a heat pump as stage 1 work correctly.