Ac compressor won't kick off

Sounds like it is low on Freon, or whatever they use in them today.

Hi,

You have plenty of freon, or it would not be freezing up.

You have a bad thermostat. It should be shutting off around 65F.

Fred.

Thanks. Now I just have to figure out how to change it. I don't have a wall mounted tstat for the ac.

Could be a stuck (welded shut) control relay inside the ac unit controlling the compressor.

Larryect wrote:
Could be a stuck (welded shut) control relay inside the ac unit controlling the compressor.

Had this happen twice while living in an area with "dirty" voltage. Would regularly swing from 90-120v. The lower voltage results in higher amperage with the same load and welds the relays.

So what would I need to do to fix this? Do I need a whole new ceiling assembly? I'm assuming the ac on top is working just fine. This is a ducted ac.

Are you running fan speed on low? That can cause freeze up at times. The "AC" on top is where the goodies are, the ceiling assembly you mentioned contains the control box, connections from the T/S and "top" unit. Try it with fan on high before you panic.

Jim

Diagnose things first. What does the ice look like? If it is white and frosty looking it is an airflow problem. If it is a hard clear ice then it is either a drain problem or possibly low refrigerant charge. However, yours is a bit different so I would suggest that you shut your A/C off, turn off the breaker, and try disconnecting the thermostat (temperature control knob). Make sure the wire(s) are not touching anything and turn the breaker back on. Does the A/C run? If not then the thermostat is the problem, but if it does run then you need to find a relay or contactor that is stuck shut. This it where the wiring diagram comes in handy.
Tom

Ok, thanks all. I'm pressure sure it is the thermostat. At least, that is what my gut tells me. I ordered one up and will let you all know if this solves the problem.

sherpaxc wrote:
Ok, thanks all. I'm pressure sure it is the thermostat. At least, that is what my gut tells me. I ordered one up and will let you all know if this solves the problem.

Is your gut a qualified technician? This sounds like a good plan to toss money at a problem with litle hope of success.

Jim