Home air conditioning maintenance

Joined
Dec 31, 2017
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Location
SE British Columbia, Canada
My “American Standard” Heat pump is ten years old. Currently, the interior fan is blowing but the outside unit is humming and the exterior unit fan will not come on. It’s hard to get a technician out as it’s 97 F and they are all out on calls and days behind. I understand a very common failure point is the capacitor. Careful to work safely, I’ve extracted it and am headed into town to get a new one. Wish me luck. Any other advice on what a non tech can check? Here’s a few photos. I have since cleaned things up. The pine beetles like to hide out here in the fall and they croak over the winter. Thanks.

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The fan motor itself may be the problem. Some of the high efficiency units use a DC variable speed motor and they are prone to failure (mine is a DC unit). If it has a conventional 1/8-1/3HP AC motor it is easy to replace and can be sourced locally. I'm not an AC expert, but I don't know if any American Standard fan motors use capacitors.

Anyway, just in case you don't get it going:

Emergency fix: Take a big box fan or strong round fan, and place it on top, blowing up. Use wet towels to seal the area around the fan. It won't have the same power as the built in fan, but it will get you cooling again. Also, you can use a hose to cool the condenser while it's running for more effective house cooling.
 
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Capacitor looks buldged. I would bet the cap is your problem. I would also order a new contactor. That's the black item next to the capacitor. Hopefully, you hear a loud click when you try to turn it on which is the contactor. If you do not, the 24v feed for the contactor's coil could be missing. If you get it running and you get 17-20 degree spread across your evaporator, you do not need a technician.
 
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If you're leaning towards the Capacitor, they can be checked visually along with using a multimeter.
► Visual inspect for bulges
► Using multimeter, check to see if
1) Not shorted out
2) It's releasing its charge
3) MicroFared reading (need multimeter that reads MF)

Note: Before handling a capacitor, it should be discharged by touching the connectors with a 'plastic' handle screwdriver.

Capacitors are not expensive.
Other appliances in your home also have them and it's good to learn how to check them.
It sounds complicated but was easy after watching videos on YouTube.
 
My “American Standard” Heat pump is ten years old. Currently, the interior fan is blowing but the outside unit is humming and the exterior unit fan will not come on. It’s hard to get a technician out as it’s 97 F and they are all out on calls and days behind. I understand a very common failure point is the capacitor. Careful to work safely, I’ve extracted it and am headed into town to get a new one. Wish me luck. Any other advice on what a non tech can check? Here’s a few photos. I have since cleaned things up. The pine beetles like to hide out here in the fall and they croak over the winter. Thanks.

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That capacitor is shot. When they puff up means it’s shot. Put a new one in and order a spare and try to get US made one.
 
I didn't think the capacitor had anything to do with the fan motor. I thought they were for kick starting the compressor only. I could be wrong but that capacitor does look shot.
 
If you have a multimeter that reads MF, be patient. I tested my new capacitor and the number that came up was way off. I discovered you must keep the leads connected for at least 10 seconds to get a good reading. This delay may be unique to my Extech 330 multimeter.
 
Same exact thing happened to me several years ago. Based on advice from this forum, I discharged and replaced the capacitor with one from Amazon and its been working fine ever since. I also bought a spare for our second floor AC unit so I am prepared when it happens in the heat of the summer. Be careful handling the capacitor before its been discharged. It can be a real eye opener.
 
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