Trane central air unit quit doing its thing (recently made another post about it) and I finally cracked open the housing.
Here are some pics - front and rear of a capacitor and a pano of the electronics. Am I mistaken or is the cap leaking stuff out that it's not supposed to be leaking? If so, under what heading in the yellow pages should I be looking for replacement pieces?
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Anything else you see that stands out as being obviously bad or suspicious? I can take closeups of anything you want a better look at.
5/370 should be the cap for the fan. Looks like the terminals are pretty badly rusted. GE had a bunch of bad caps. I'd be wanting to test that one for farads, and then replace it regardless of the reading.
I notice you have a big round cap (can't tell if it's double value, but at the moment it doesn't look like it) to the left.
You likely won't find replacement AC caps sold at retail. Might try "capacitors" in the yellow pages.
How do you know it's the cap? You have to start with the basics first. When you turn down your t-stat to turn on the A/C, the contactor should click closed. If it doesn't, you have to look at that first.
Actually the big horizontal fan at the top runs, the basic problem is the compressor isn't engaging. First noticed due to no "quish-quish- gurgle" in the freon line inside going into the air handler as should be happening. A few months ago when it was last fired up it was doing fine.
They are.
I did find a couple of dessicated dead lizards hung up in the electronics.
With the power on and the thermostat set for cooling, get a volt meter and check across the two bottom screw connections on the contactor ( the brown and the red wires). If you are reading voltage, the contactor is bad. There should be "0" volts across those two if the contacts are closed. The set of contacts on the top of the contactor control just the fan motor on that particular unit. (some of the older Tranes are wired a little screwy) Larry
That fan run capacitor looks like the crimp on the top is damaged and leaking. Those things cost less than $10 around here. The start capacitor terminals and top looks burned from what I can see in the picture. That capacitor is less than $20 in this area. If you found critters in the control box, the circuit board could have been damaged and that's the most expensive item $60-$100. If you can't get an HVAC supply house to sell to you, try an electric motor sales and rewind company. Either supply houses will have a capacitor tester and most will be glad to test the capacitor for you. Dress like a working man and you may get away with it. If you show up wearing an Izod knit shirt, white shorts and deck shoes, the city sales crew might get suspicious. *snicker*
My thoughs exactly. The contactor usually has 2 seperate terminals, one for the fan and one for the compressor, so its possible for one component to work and not the other. If everything checks out, you could be low on freon, which will prevent the compressor from turning on. To check, you can bypass the high pressure switch for a few seconds to see if the compressor comes on.
Find a HVAC supplier in your area that sells to the public. That's a pretty popular value and should be stocked. If the compressor hums when the relay kicks in it could be that cap. I would also change the run cap and the fan cap. Take a close look at the contacts on that relay. Make sure when you button it back up that the electronics can't get wet.
Looks like a heat pump to me? Isn't that a defrost board?
Most hvac supply places won't give you much grief if you just show up with a cap and ask for a new one. Don't start asking them troubleshooting questions though. See if you have a johnstons, they carry a lot of stuff.
I think that's the fan cap though so while it might be leaking a bit it's not your main problem. Use a vom to check and make sure you have
240 vac on the downside of that contactor. You could try replacing the compressor cap since it won't cost you much. You need to observe it to see if it even tries to start. You can do that either by having a helper turn it on while you are there or push the contactor in yourself with an insulated screwdriver. It's ok to run the unit for short periods without the fan on top. You can tell when a compressor is trying to start as it will make noise for a few seconds and then quit. Compressors have thermal overload switches inside them so they cutoff after a bit if they can't start. It's a lot easier to tell what it's doing or not doing with the fan removed. With out gauges and other test equipment it can be difficult to fix hvac systems. You can try simply replacing the cap on the compressor but after that then you need to check the charge and possibly the current draw if it's trying to start. A hard start kit might help too.
Don't know about trade shops in your neck of the world, but here, in this economy, they don't care about who you are as long as you have money to pay for the items. Regarding the tax, here it is a VAT tax and they collect it from everybody, in or out the trade.
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