Wyze thermostat fan before heat

Is there a way to delay the fan until the furnace kicks on and flame has started? My old therm wouldn’t turn fan on until about 30 sec to a minute after it turned on so the furnace could heat up. The fan now just turns on first and blows cold air for about 30 sec or more before it heats up.

Welcome to the forums @chrisdanelle0414

might that just be moving the cool air out of the ducting? depending on how big the home is ( and thus the venting) it might take a sec to get the warm air circulating through…

I wish that were the case. My last therm would turn on the flame before the fan started and yes, there would be some cold air at first but this is different. The fan just blows without flame being lit for at least 30 secs ( I stood and watched this while it was working). Most new systems should come with built in fan delays or if it is set to gas it should know that it takes a minute for the flame to ignite. Didn’t know if I missed a setting or if maybe this was an oversight that would be fixed.

I do not know enough about your particular hvac to give a good answer on that one. I’ll have to check on some things to give any good feedback on that one…sorry I can’t be of more help right now

Thank you very much for trying. I might just need more time and self troubleshooting. Normally I would figure out myself but work has given me no free time. Lol

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Just got my thermostat installed yesterday. Noticed the fan blowing for a while before the gas heat kicked in. I changed Settings - Behavior from the mid-comfort level to the mid-savings level and that seems to have helped a bit. Otherwise, happy with my new thermostat!

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Thank you for the tip but unfortunate this didn’t work either. Besides this happening I absolutely love this thermostat too! This is far from a deal break but would be great to figure out.

make a Wishlist item for it. if it is something in the settings that we are overlooking I GARANTEE someone will be quick to point it out :wink: and then we can move the Wishlist topic or get rid of it. but being so new I haven’t seen anything like that yet.

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good info. I wish we had some more insight as to what each settings in behavior did.

After looking it over a little more I think I know why. I had to use the converter and to do that you have to change the G wire (fan) to the C spot since I don’t have a C (power common). Doing this pulls away independent controls to the fan so it just turns ona nod off with the furnace. Maybe I will find a work around in the future or possible I am wrong but this is all I can find as of yet. Thank you all again for being so quick to respond this community is great!


I have the same issue. But I’m not using the C-wire converter. I have R, W, G and C direct connect between furnace and thermostat. I found that when heat on. The W and G wire energized at the same time. That made the fan turn on at high speed before the ignition. That doesn’t sound right. W should be the only wire energize when heat on. As of now. I disable the G wire. Setup as 3 wire R,W and C to work around. It works but I lose the cooling fan only feature.

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Found out I did have a C-wire so I took out the converter and setup again. Still have the same problem where the fan turns on right away before heating up first. Back to the drawing board.

I disconnected the G like you did and now it works. I don’t usually use the fan Independently so it wasn’t a bother for now. Maybe they will have a fix in a later update. Thank you so much for the tip.


Similar issue.

Old thermostat - heat demand
-sends signal to initiate heat (white wire). Heater (not thermostat) would then send signal to fan after about 30 seconds after ignition.

  • thermostat did NOT send signal to fan (green).

Old thermostat - fan only demand

  • as expected: when in fan-only mode, thermostat would send signal to fan (green) and NOT to initiate ignition (white).

Wyze thermostat - Heat demand

  • as unexpected: simultaneously sends signal to initiate ignition (white) AND signal to fan (green). I only want ignition and NOT fan (green).

Wyze thermostat- fan demand

  • as expected: when in fan-only mode, thermostat sends signal to fan (green) and NOT to initiate ignition (white).

It’s a know “feature”, there are a few posts on here and we got one of the Wyze team to actually respond to us awhile ago. They decided it was a good idea to do something no other thermostat manufacturer does and override the fan controller on your system and force it to come on using the fan control wire. Unfortunately we are stuck with a blast of cold air until they release new firmware for it.

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