Why Does my AC Turn on When It's Set to Furnace
Updated 12/29/2025 | Published 11/28/2025
Question:
Why does my rooftop ac come on when I put the thermostat on furnace? How do I stop it from happening?
asked by: Joseph R
0
Expert Reply:
Hey, Joseph.
I'd be happy to look into this for you. If you comment with your AC, thermostat, and furnace model numbers I start researching. I couldn't find an order at all with your email or name so I'll need that info from you.
Look forward hearing back from you!
expert reply by:
Gwendolyn Y
0
Product Page this Question was Asked From
Replacement Single Zone Thermostat for Dometic RV Air Conditioners - Black
- Accessories and Parts
- RV Air Conditioners
- Thermostat
- Black
- Dometic
more information >
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Gwendolyn Y.
12/29/2025
Hey Joseph, were you able to track down the model numbers for your AC, thermostat, and furnace? Once you have those, I can help figure out why the rooftop unit kicks on with the furnace setting. Let me know what you find so we can narrow it down.