Originally Posted by Kestas
Originally Posted by JMJNet
Check the capacitor every year and replace as necessary.
A lot of AC issue happens when capacitor went out.
It is not a bad idea to check what capacitor is used in the unit and have spare at home at least 1 for each type or get one of those multi capacitance capacitor.
A unit will have at least 1 or 2 running capacitor and 1 starting capacitor.
As long as we're on this topic, how do you manage capacitors in HVAC units? What do you look for, and when do you replace them?
My unit is 34 years old... original furnace and a/c. The a/c isn't used much here in Michigan. It'll likely die from corrosion before it wears out.
Capacitors are a crapshoot. I mentioned a replacement that lasted only 14 months, then replacing that with the exact same thing lasted over 3 years before the whole unit was replaced.
Few people replace them preemptively, instead waiting for failure. When they fail they fail fast, will bulge on the end instead of being flat. It is a great idea to have a spare already if your unit is getting older.
The failure is pretty obvious when it happens, the motor starts making funny sounds instead of spinning, but the one I repaired was in an area right next to a garage and frequently used entrance door so the owner was in and out often enough to notice that.
Anyway the motor could have shot bearings/bushings instead but if you (shut off power to it first) and can spin the blades without resistance, it's probably not the motor. Windings could short out but that would usually trip a fuse and regardless the capacitors don't usually last as long as the motors so checking the cap first gets to the most likely problem the fastest.
Lastly, "lubed for life" fan bushings is nonsense. It just means the fan will fail if the bushing runs out of lube and will last MUCH longer if you use a very light oil to lube every few years. Once upon a time ago they used to have lube ports, even tubes going to the ports to squirt some oil in, but in recent decades they saved 20 cents by omitting those so it takes more labor to get to the bushings to lube them. On older units then often have a felt/other reservoir so you can get quite a bit of oil into them but make sure you don't over-oil to the point where it's pushed out into the rest of the motor.