Hi all,

I came home last night and my York a/c unit was not working. It appears to be completely dead. It has been working fine. It is dead silent. No fan, no condenser, nothing. I live in Columbia, SC so it is crazy hot here.

The thermostat appears to be fine. Turning the fan switch off/on does nothing. The thermostat reads the correct temp inside but is not affecting the unit.

The breaker inside was not tripped. I flipped it off and on a couple of times but nothing happened. It may be dead.

Outside I opened the box next to the unit and pulled the handle. I then replaced it and nothing happened. I know that there are two fuses inside that box. One of those or both may be bad.

My gut tells me to test the breaker inside and the fuses outside first. Is this the right way to go?

Thanks

 

I am not an a/c guy, but yes, that is exactly where I would start. As long as you have a meter and are comfortable doing so, that is the place to start. You should have 120 volts at the bottom of each fuse and 240 volts across them. If not, check at the tops of the fuses. If nothing there, then I would remove the panel cover and check at the breaker.

 

First step in any electrical troubleshooting. Be sure to do it safely. Next step, I think, would be to check the main contactor (the big relay that kicks on to deliver the juice).

One of the AC pros should be along with more guidance.

 

Pedro types faster than I do.

 

So I ran home during a break and tested the two outside fuses. One of them was indeed bad. I replaced it and the unit fired right up.

BUT. The fan did not turn on...I am not sure if the fan stopped yesterday and the unit overheated causing the fuse to blow??

I took a long screwdriver and reached through the grill and gently tapped the fan. It started moving as it should. I stayed there for a couple of minutes and it worked fine.

Could the fan motor be going bad? I feel like that is something that I could replace. Or maybe it is not getting the right power signal from the circuit board.

I am going to run home at lunch to check on it. It was 82 inside my house. You gotta love SC in the summer.

 

Again, not an a/c guy, but sounds like you were hurrying, so maybe you'll get lucky and it was just happenstance that the system said "go" about the time you gave it a nudge. So see how it performs when you get home, but no, that's not the way my luck usually goes either. I would guess though that the most likely culprit at that point would be a capacitor, and believe you will find that inside the access panel on the back of the unit. Shut the power off of course, then take a peek inside. Sometimes those capacitors will swell up when they go bad so it can be that easy to tell. I'm sure someone more knowledgeable will pipe in, but I think it likely enough that if it were me I would just go ahead and replace it and see what happens. If you're going by a big box or industrial house on the way home you should be able to pick up a universal capacitor and at least have it for future use. That's what I keep on the shelf. I think they're around $50-60, and have extra terminals so you can stack the mfd's to get whatever you need to match the spec's on the original one.

 

so... Here is a pic of my unit on the inside. Is the capacitor one of the ones on the board?

 

No, not on the board. It'll be to the side, I don't know, don't deal with them regularly, but say something around 2-1/2" diameter by maybe 6" tall.

 

Here is another pic with a capacitor. Is this the one I need to look at? How many different capacitors like this are there in a unit?
Also, I am attaching the manual for my unit. I have watched a couple of videos on replacing the capacitor. I just want to make sure that I know where to look. I am sure that it is obvious and will be easy to find when I get home.

Thanks

 

One is all I have ever seen, and yes, that is it. Power OFF obviously, then keep in mind that a capacitor stores energy, so you will want to discharge it, which you can do by crossing the terminals with an insulated handle screwdriver. The terminals should be marked, so make yourself a sketch of which wires got to which terminal.

 

Hi all,

It was indeed a dead capacitor. I removed it and tested it. Dead. I was able to get one here in town for less than $20 and it took me less than 10 minutes to install.

Thanks for all of the guidance.

 

................. Good job!