Trashpicked Carrier Window Air Conditioner with a Problem

UPDATE: This air conditioner has been FIXED. Please don't post any more repair suggestions in the comments. The problem was a bad thermostat.

I found this mostly functional 1989 Carrier 8,000 BTU air conditioner in good condition set out for the trash collection. I found out why later--the air fan will start out OK and gradually slows down as the unit has been running until it is only humming. The compressor runs fine.

Category:

Science & Technology

Tags:

• 1989
• carrier
• window
• air
• conditioner
• fan
• problem

[compdude957]

Hey, i am wondering if this could possibly be the problem with the window a/c unit i found on the curb. The fan on mine will stop after about 20-25 min but then 5 seconds after it stops it starts back up and runs at the speed you set it at with no problem, but then another 5 seconds later it will stop again and the cycle repeats. Medium and low speeds i haven't seen it do it, only on high. Help would be appreciated, i want to try and fix it so i can keep it as a backup if my central ac dies.

[uxwbill]

@compdude957 More likely than not, your fan motor is cutting out because a thermal protector is opening up, resetting and then opening up again.

The motor could be bad, but I'd make sure it has had both bearings oiled, that it is clean and can turn freely before confirming that.

[aranacmac]

you have a winding to winding short in the motor

[uxwbill]

It was a bad thermostat. It's long since fixed.

[Mooseguy15]

@uxwbill weird never heard of the fan shutting cause of the thermostat lol

[uxwbill]

@Mooseguy15 That's why it threw me for such a loop for so long.

[compdude957]

@uxwbill Interesting, thing is i wouldn't think that it would have a thermal cut off for being so old. The unit i have is from 1974. I was thinking that it could even be the capacitor for the fan, but im not sure. I tried oiling it before but could not find any oil ports so i sprayed some lubricant where the shafts go into the motor. I will have to take a harder look at the motor this spring and try to oil it more. Thanks for the info!

[tlaroche38]

I cleaned my filter and mine stopped doing that!

[Mooseguy15]

@uxwbill yeah cause normally the fan is constantly on even when the thermostat shuts the compressor. but since everything is really connected to the capacitor maybe a bad thermostat coulda interfered lol

[pcwalker]

That's great! You find old A/C units to fix, too. My friend and I found one in a creek bed and split it, put in a new fan for the evaporator and condenser, put in new refrigerant and it cranks out some cold air again. Later on, we got a programmable thermostat. It was a nice project. Our only problem was the water. We had to find a way to get the water out of the house.

[christianpasco]

thank you