0

I have a heat pump for my house's heating and cooling. We had our first hot day of the year last week, so I switched it to cool mode (heretofore it had always been in heat mode). When in cool mode, however, i have no air flow at my vents. The air handler is on (there's sound), but it's not as loud as it usually is. I think the fan isn't running. I opened the chamber where the air filter goes, and I didn't feel any airflow. Furthermore I see ice crystals forming on the refrigerant lines. In heat mode, everything works fine (the fan comes on, and there's plenty of airflow).

Is this a problem that I can diagnose/fix myself, or should I call an HVAC company to look at it? It's an old system I'm planning on replacing in the next year or so, so I'm hoping to not put a lot of money into fixing it if possible.

  • Does putting the thermostat system switch OFF and the thermostat fan switch ON (from AUTO) work? – ThreePhaseEel May 21 at 22:58
  • Looks like setting the thermostat to FAN doesn't do anything. It's quiet – atanamir May 21 at 23:39
1

Your blower motor's HIGH speed died

Most furnaces and split-system air handlers run their blower at a high speed in FAN and COOL, and at a lower speed in HEAT. As a result, it's possible for the blower to work when the system is set for one mode, but not the other. I would consult the manual for your existing air handler/furnace for instructions on changing the blower speed used during cooling and fan-only operation. This will change the latent/sensible balance during cooling, but will at least keep you running until you can get the blower, or the whole system, replaced.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.