Capacitor for Air Conditioner 40 uf MFD 370 or 440 Volt VAC, Multi-Purpose Round Capacitor for AC Motor Run or Fan Motor Start or Condenser Straight

I have been a ARIZONA registered master heat pump technician for over 25 years.The problem I have noticed with capacitors is that many of them are defective out of the box.The reason I say that is I test the microfarads while the capacitor is under load which will tell me it’s exact microfarad rating. This is done by checking the amps and volts wile it is running. I use what I call the 2652 method.The simple formula is Start Winding Amps X 2,652 ÷ Capacitor Voltage = Microfarads.Sample: 5 amps Times 2652 divided 369 volts =35µFThis is the correct way to test a capacitor. There are meters that have capacitor testers settings on them but I never used them because they are pretty much useless unless you just wanna know what size it is. You need to put a capacitor under load to make sure it doesn’t have any leaking Through that dielectric.This capacitor I have bought several times and it is exact to what it is rated at.Some brands of air conditioners you will find bad capacors on every one of them when you fire them up new. I don’t wanna mention any names but one that does this the most makes air conditioners that start with the letter C and another brand with the letter B. They actually buy rejected capacitors for their units to get them cheaper so sad.It’s very important to have a correctly size capacitor to create a third leg properly. This is basically making a third phase. If you’re capacitor is leaking electricity through the dielectric it will shorten the life of your unit. About 25% of brand new air conditioner run capacitors do not pass the test.They can only be as far as 10% off of what they’re rated at is there any greater than that it’s best to throw them away. It’s also a good thing to change your air conditioning run capacitor at least every four years. In hotter states possibly more often.They make a 370 V and the 440 V capacitorsI highly recommend going with the 440 V rating it will put up with more heat and will last longer.The 440 V rating only means how much electricity it can handle. So it’s basically heavier duty than the 380V ones. Your air conditioner might be 220 V but when the compressor is running the voltage across the run cap can double that. So be warned if you’re going to test a live Ron cab you’re going to have to be extremely careful because the voltage coming off that run cap can kill you.With that being said I recommend this brand.

My heat pump stopped working. It would buzz for a second while trying to start and then trip out on overload. I had a locked rotor condition. The run capacitor acts as a start and run capacitor. My run capacitor was not doing its job as a start capacitor. So I got a replacement for the run capacitor. To prevent the new run capacitor from failing as a start capacitor, I added a kick start capacitor in parallel with the run capacitor. It stays in less than a second in the circuit and then kicks out. No problems with this 70uf run capacitor running my heat pump.

Was nice while it worked. Was used for a swimming pool pump. Even though I had it for 8 months, it was only in use for two weeks in September of 2021 and just short of 4 weeks in 2022 before it swelled. I most certainly do not recommend!!

Watched a YouTube video then fixed my air conditioner. Could not go wrong trying this fix since it was so inexpensive. Air conditioner began working immediately after install. Saved me quite a bit of money PLUS I did not have to wait the one week for the repair guy to get here in 100+ degree temps. Will keep a spare backup. I am not electrical savvy and this was super easy. Plug and play.

unfortunate replacing the Capacitor did not solve my issue (a more expensive item did), but I left it installed, and works still great. Fast delivery was also a very big plus. Hopefully I wont need another if, if the time comes, I will definitely order the item again.