Air Conditioning - A/C not cooling!

Just noticed that A/C stopped cooling, but evap blower is running.

All the C/B's and fuse boxes are good and noticed the condenser fan motor is not running. The motor is hot, so I'm assuming the fan motor is bad!!!

Here's my question!!!

Just got dark here in Miami and plan on checking unit in morning with meter. Is there a condenser fan contactor or is it wired with the compressor? Is it located with the condenser unit or possibly with the airhandler?

It's a Trane Allegiance 12, 208v.


Thanks!!!!!

Joey

Check both fuses in the disconnect.
The coil & contactor are inside of the condensor unit.
The signal to start comes from the T-stat and passes thru the air handler. Doubtfull that this is the problem.
Or you could have a bad motor. Not all bad motors pop fuses or trip breakers.

When you locate the contactor.With power on, you will see the coil (1 or 2) little holes on the contactor, With a screw driver pushh them in to manualy run the fan. (this is just a test and the fan will stop when you release it. That will determine the status of the motor.

ONLY do this if you are comfortable with it.

If the fan turns easily by hand and ohms out ok, check or change the capacitor.

This happened to me a few weeks ago. After calling out a tech, all it needed was to be shut off (from the thermostat), let rest for 5-10 min, and restart. The tech said it was probably a power sag or something that caused the compressor to shut down, and since the fan kept running (as the house got warmer), the compressor never kicked in.

It's been running fine since.

He also installed what he called a "Hard Start Kit" that "gives the compressor an extra 'kick' when starting up." I presume it's an additional capacitor or cap/relay, but I'm not certain.

It probably isn't this simple - though I'm crossing my fingers for you. :)

-Mike

Thanks for the advice everyone!!!!!!!!!!!

I'm an electrician on passenger trains and repair A/C's and refrigeration systems. The only difference is the systems are HVAC, 480VDC.

This advice will help alot!!!!!!!!!!

After letting unit cool off a few hours, I checked again and the compressor is running! Looks like a bad fan motor or contactor. Turned off since freon is not cold enough to cool windings!!!!

Thankfully, I still have my wall units in the bedrooms!!!!

This advice will save alot of time, now that I know where the components are located!

Thanks!!!!!!!!

Joey

Sounds like the freon is low, and the unit is droping out on pressure.

Good answer,
How did we all miss the most obvious?

One of the beat ways to just check on the freon In a unit from time to time . Big copper line cold and wet small copper line warn to hot by outside unit. When unit is running.

ED

Foxbat, When the unit is calling for cooling, give the condensor fan a push start with a small stick. If it takes off and runs just replace the capacitor. If it resists or don't take off then I would guess you need a new fan and capacitor.