Central Fan Motor Not Starting
Today I wanted to show you how to fix a central fan motor if it was not starting after being turned on. This one actually is turned on. Earlier, it was buzzing before it would start. What I do is unplug it up top here. And just show you– very similar to the condenser fan motor. What I was able to do was push start the motor. It was buzzing.
It was just going errrr, and it wouldn’t start. And I was able to push start the squirrel cage portion of the motor. I can’t see a thing. But what it’s telling me is that our capacitor is starting to get weak.
[MOTOR BUZZING]
OK. I got a fan motor that’s not starting up, here. You can hear as I just plugged it in, that it’s not starting on its own. So what I’m going to do is just kick start it with my pen.
[MOTOR STARTS]
I was able to turn the squirrel cage. Now don’t try that at home or at work. But just understand that what that means is that it’s time to replace the little capacitor that’s on the side right here. You can hardly see it, so I’ll try to open this up so you can see it better.
Let’s see. Up here, see on the side, there, the little 5 microfarad capacitor. We’re going to need to change that one. So I’m going to go ahead and pull the plug right here. We’ve got our fan turned on to on. And then we’ll replace that capacitor right there.
So you usually don’t have to slide the whole motor out in order to do this. You can actually just do it right here, in place. So you can see it right there. And what I have to do is loosen that, first, feel with my screwdriver.
Now, my screwdriver’s usually too long to fit in there. So what I do is take all the pieces out of my screwdriver and then just use the end of my screwdriver, here. And before we do that, we want to discharge the capacitor, so we need to move the little cap down on the capacitor, right here, and then discharge by bridging the leads with my insulated– holding only the insulated portion of my screwdriver.
Let’s see if I can remove the front panel here, to give us some more light. A little better there. OK. And the reason we discharged the capacitor by bridging the leads– see here, I’m using the non-insulated portion, but I’m holding only the insulated portion of the screwdriver to bridge the leads in the capacitor.
And that discharges the capacitor, because the capacitor holds a charge in the capacitor, even after the unit’s unplugged. Something you should know. So anyway, bridge the leads, like so.
Most times, I’ve got my flat screwdriver here and just bridge the leads like so. OK. So we’re going to bridge the lead on these holding only the insulated portion of my screwdriver and bridging the leads here.
And then I’m just going to take my little driver out of the handle, in order to remove the clamp for the capacitor, right here– on the side right here. And then I just take my pliers and turn this out like so. So there’s just not enough room. If you have an angled screwdriver, that could help.
But anyway– so we’re going to slip the capacitor out. And now we can change our capacitor here. So down right here. Here’s our old one. And we just slip the leads off and there’s just one on each side.
We don’t have to worry too much about our old one. If we bend it, not big deal. Of course I got a stubborn one here. There we go. OK.
Same with the other side. Slip both of the leads off there. OK. So here’s our two leads, and it’s just one to each side on the new capacitor. OK. Here goes the other side.
Sorry for the lack of light. Not much light, here, but hopefully enough. So then we just slip our black cap back over the top, here– slide it down. And now we’ll slip it back up and remount it back through the screw here.
Took my handle-less screwdriver and I’m going to screw it back in there. Now we’ve replaced our capacitor. OK. Fairly simple, there.
Remounted our capacitor, there. Nice and tight. Now I’m going to remove my [INAUDIBLE] back on. OK. So we can put our service door back on.
OK. And now we can plug it back in, and it should fire right up. And if it didn’t, it’s time for a new motor, but it should. Usually, nine times out of ten, it’s just that capacitor that gets the fan motor going. And there we go. Good to go.
Replaced the little 5 microfarad capacitor. Now when you replace capacitors, you always want to equal the same microfarad. So you can see this, is a 370VAC– probably can’t see. This one is a 370VAC and a five– it’s got the little UF– 5 microfarad capacitor.
So you always need to equal the microfarads for a new capacitor, but as far as the voltage goes, you can go up, you just can’t go down. If you’re starting at a 370, you can use a 440, but you can’t use a 240. Just so you understand that.
Anyway, good to go. Air conditioning working again. Good. Good.