NO Heat with Thermostat.. A/C works fine

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1

Fails heat test, heat does not come on. see pictures.
I have a natural gas furnace, and a external A/C air pump.

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I am a little disappointed. I’m a wyze fanboi, but this is by far the most frustrating device i’ve installed. not sure what could possibly be wrong. fails the heat test, A/C comes on passes the cooling test. worked with Google Nest just fine until the display on it died.

3

Hmm. everything looks correct.
When you hooked it up, did you tell it that your heat source was gas/ forced air?
if you put the panel back on the furnace and look through the window when it is calling for heat, does the led flash any codes?

4

have not tried that. does the panel have to be on? there is no window to look through to see codes.

5

usually the furnace will not run with the door panel off. there’s a safety switch that cuts power when the door is open. if yours will run when the door is off, then that works too. tell it to try to heat and see what the status leds on the furnace control board tell you

6

so when i set the heat on, the furnace appears to come on, i can hear it, but the fan never kicks in, then the furnace stops after about 2 mins. Also i found my original thermostat. it had a loop wire run from RC to RH? not sure if that is helpful. The google nest thermostat did not have that loop. it was wired the same as the current wyze thermostat. I feel like I may have an issue with my furnace, the house is only 6 years old, i would think it should be good for better than 6 years?

7

Ignition without fan is usually the flame sensor.
could be pressure switch related too, or the gas valve.
the led should be flashing some sort of error code when it turns off the gas instead of powering up the blower fan

8

so when I got home tonight, I pulled the cover off the furnace and watch the start process (after spending the day on youtube watching videos, i’ve become pretty knowledgeable on furnaces lol).

This time the furnace actually started as it should. while i was observing i noticed the vent limit switch is very corroded with rust. My guess is that this is the problem. I plan on replacing it and going from there… it must be faulty but not completely out of order.

I really appreciate your help on this. thank you!

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