The outside unit is making a squealing noise. It's every now and then; not constant. Just started today. What's wrong? The fan is running fine. The air inside is cool. Just a high piercing squeal every now and then from the outside unit. Any ideas?

Assuming you mean the indoor unit, you're no doubt correct. Modern fan motor bearings can't be lubricated. It's a new fan motor to fix this. It will run with the noise for a few days, then lock up totally.

You should also report the continuous run to your HVAC repairman. At 32 degrees outside, I would think there should still be enough output from the heat pump to cycle. Perhaps low on refrigerant or a compressor that's losing. He could check both before you decide on the fan motor replacement.

15-20 years is about the max life on that unit. You may be better advised to replace it than throw a few hundred dollars here and there into repairs.

A grinding or rumbling noise can also be symptoms of a wheel bearing or constant velocity joint in a driveshaft. A worn wheel bearing can also cause a 'whistling' sound (as can a worn CV joint).

A grinding noise with brakes is either worn pads causing metal to metal contact on the brake disk/rotor, or the brake backing plate catching on a spinning rotor ... or a loose/missing anti squeal brake shim (they stop the pads from rattling and vibrating).

However, as you say a mechanic has looked at the brakes and can't find anything wrong .. I think I would begin to suspect a wheel bearing or constant velocity joint on the driveshaft (front wheel drive cars).

The bearings are bad in the motor and after the fan runs enough it eventually gets hot, making the bearing screech and the fan locks up. Need to replace motor again. See if it has a warranty. The reason it gets hot is because the fan is what removes the heat from the coil and if the fan isn't running there is nothing to cool it off so to speak.

Should like your unit is working fine unless this is constantly happening. If this is a constant thing then condenser coil if dirty,check thermostat setting

To my recent experience the keyboard had to be replaced. It had something spilled on it unbeknown to the owner, making it squeal. I ordered a replacement, installed it and viola! No more squeal.

Let's start out by your statement that the fan would not run, then you changed the contactor, not it won't stop running.
I believe, based on your info, here's what you need to do. Kill power to the unit. The 2 wires bringing power to the outdoor unit should be on the top 2 terminals. The 2 fan wires should be on the bottom 2 terminals. This is providing that the contactor is mounted Vertical. The could be an outside chance that the unit has a short in it and you are getting voltage feedback somewhere.
Take another look.

You amy ahave a bvad capacitor on the outside unit. It starts the fan and the compressor. You can change this yourself. Open the outside panel and you will see a silver canister with terminals out the top. Replace this and I think your problem will go away. On the cap. it will say something like 30uf 5uf 370 ot 440 Just get these numbers and get a new one. Russ

Hi!
Self-defrosting refrigerators use a circulating fan to move the air through the freezer and refrigerator compartments. This fan runs whenever the unit is cooling. The fan is located in the freezer.
Over time, the fan may become noisy--usually making a chirping or squealing sound, though it may make a loud groaning noise instead.

To find out if the fan is causing the noise, just open the freezer door and push any fan/light switches. If the noise is louder when the door is open, the evaporator fan motor is the cause which can't be lubricated or repair instead required to be replaced.

Please do rate this solution as FixYa and revert for further assistance.

Thanks
Rylee

https://www.fireplaceparts.com/10006404-fan-heater.html

This is for the pyromaster hef33 2004. This site has 02 thru 05 parts for the pyromaster.

Raise your thermosat to about 78. Also check to make sure the thermostat is set to auto and not on...