I've had two caps blow on my AC units. The first time it just broke. The second time it literally blew up. There was a lot of black smoke under the cover. The prices can vary widely for them. First time I bought one it was $40. Then I found a place that sells them for $8. I have some spares at home.
Residential A/C Capacitors
- Thread starter Merkava_4
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Originally Posted By: 65f100
Don't buy Chinese run capacitors. Pay the extra and get made in USA.
THIS!!
Unfortunately, I think a lot of newer units are coming with chinese units installed, .................which will last until 3 days after the warranty has expired.
Don't buy Chinese run capacitors. Pay the extra and get made in USA.
THIS!!
Unfortunately, I think a lot of newer units are coming with chinese units installed, .................which will last until 3 days after the warranty has expired.
Originally Posted By: rshaw125
I had to install a contactor last year, ants.
Very very very common.
The points can often be cleaned with 600 sandpaper & reused.
I keep a universal fan motor (long shaft, cut to length)
These always fail on the eve of a 3 or 4 day holiday weekend.
I had to install a contactor last year, ants.
Very very very common.
The points can often be cleaned with 600 sandpaper & reused.
I keep a universal fan motor (long shaft, cut to length)
These always fail on the eve of a 3 or 4 day holiday weekend.
It depends. You can buy good capacitors from China as well. They won't be as cheap, of course. My employer, Lennox, sells a product line called "First Choice" and the capacitors are actually quite decent. I installed one with my new blower motor in May of 2016. DiversiTech's Chinese capacitors are pretty good, too. Overall, though, unless you know what you're getting I'd lean toward the US or Mexico sourced parts.
Originally Posted By: knerml
From my experience owning a Goodman, stock a spare capacitor.
OK but should I stock the short capacitor too ? They got me set up with one tall capacitor, one short capacitor, and one starter. Do the starters ever wear out ?
From my experience owning a Goodman, stock a spare capacitor.
OK but should I stock the short capacitor too ? They got me set up with one tall capacitor, one short capacitor, and one starter. Do the starters ever wear out ?
Originally Posted By: Merkava_4
That's where the magic of YouTube comes in. I learned that I can discharge the capacitors by laying a screwdriver blade across the terminals. I could've sworn that I heard a fizzing noise when I did that, but it was probably just my imagination.
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk. And then there's the corrosive electrolyte all over your equipment.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
As for Chinese caps, I suggest you just say no. They are by far the most counterfeited components coming out of China, so you cannot be sure that what you have is what is marked on the case, plus you probably paid too much for a premium brand sleeve over an inexpensive substitute.
That's even if you get an inexpensive substitute ... a common form of counterfeit Chinese electrolytic cap is to insert a low value cap inside a large value container, marked as such.
Don't buy electronic components on eBay sourced from China. Transistors, capacitors, ICs are all well known to be counterfeited. Plus, it's usually just as cheap to buy them from Mouser, DigiKey, etc who have documented supply sourcing and the price is usually the same, and often cheaper.
That's where the magic of YouTube comes in. I learned that I can discharge the capacitors by laying a screwdriver blade across the terminals. I could've sworn that I heard a fizzing noise when I did that, but it was probably just my imagination.
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk. And then there's the corrosive electrolyte all over your equipment.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
As for Chinese caps, I suggest you just say no. They are by far the most counterfeited components coming out of China, so you cannot be sure that what you have is what is marked on the case, plus you probably paid too much for a premium brand sleeve over an inexpensive substitute.
That's even if you get an inexpensive substitute ... a common form of counterfeit Chinese electrolytic cap is to insert a low value cap inside a large value container, marked as such.
Don't buy electronic components on eBay sourced from China. Transistors, capacitors, ICs are all well known to be counterfeited. Plus, it's usually just as cheap to buy them from Mouser, DigiKey, etc who have documented supply sourcing and the price is usually the same, and often cheaper.
Originally Posted By: Johnny2Bad
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
I've been trying to avoid the comments about the risk of death. When I was in my early 20s, I never understood the meaning of the band name "Grateful Dead." Now that I'm in my early 50s, the band name makes perfect sense.
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
I've been trying to avoid the comments about the risk of death. When I was in my early 20s, I never understood the meaning of the band name "Grateful Dead." Now that I'm in my early 50s, the band name makes perfect sense.
There are a lot of issues with Chinese made capacitor, so you really never know.
From what I read, the good ones are Amrad (US) and Genteq (Mexico).
There are universal Amrad, called Amrad Turbo.
Small (mini) ones is up to 15 mfd and 2 type for the large with up to 97 mfd.
It is universal in a sense that you can choose the capacitance by jumping different terminal.
I personally have those universal one as spare at the house.
In TX heat, we cannot wait to get those replaced when it gave up in the middle of the summer.
For starter cap, Amrad made a universal also.
Yes, in most cases, there are 3 capacitor: 2 run (fan and compressor) and 1 start.
From what I read, the good ones are Amrad (US) and Genteq (Mexico).
There are universal Amrad, called Amrad Turbo.
Small (mini) ones is up to 15 mfd and 2 type for the large with up to 97 mfd.
It is universal in a sense that you can choose the capacitance by jumping different terminal.
I personally have those universal one as spare at the house.
In TX heat, we cannot wait to get those replaced when it gave up in the middle of the summer.
For starter cap, Amrad made a universal also.
Yes, in most cases, there are 3 capacitor: 2 run (fan and compressor) and 1 start.
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Start caps are electrolytic and carry large currents- IMO they're more likely to fail than run caps.
I don't consider any of them "wear" items. They randomly and rarely fail, and they're readily available everywhere. Replace them when they fail.
I don't consider any of them "wear" items. They randomly and rarely fail, and they're readily available everywhere. Replace them when they fail.
Those Amrad caps are expensive, but very handy. I've spoken with A/C repair guys who keep a couple of each size (There are two sizes of the "universal" caps we sell) on their trucks to get someone's A/C going if they don't happen to have the right one on the truck. Then, they replace it later with the correct one so the homeowner doesn't have to pay the high price. I agree with the previous statements about sticking with branded product. I just have the luxury of being able to buy directly from the Lennox parts stores.
MolaKule
Staff member
Aerovox
http://www.aerovox.com/IndustrialProductsGroup.aspx
caps are the ones I use for replacement. Aerovox caps can be purchased from Grainger.
or
KEMET
http://www.mouser.com/Search/Refine.aspx?Keyword=Start+run+capacitors
http://www.aerovox.com/IndustrialProductsGroup.aspx
caps are the ones I use for replacement. Aerovox caps can be purchased from Grainger.
or
KEMET
http://www.mouser.com/Search/Refine.aspx?Keyword=Start+run+capacitors
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great advice here.I remember melting a perfectly good screwdriver on a capacitor when I was younger.Lucky I wasn't in the way of the current.
Originally Posted By: Johnny2Bad
Originally Posted By: Merkava_4
That's where the magic of YouTube comes in. I learned that I can discharge the capacitors by laying a screwdriver blade across the terminals. I could've sworn that I heard a fizzing noise when I did that, but it was probably just my imagination.
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk. And then there's the corrosive electrolyte all over your equipment.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
As for Chinese caps, I suggest you just say no. They are by far the most counterfeited components coming out of China, so you cannot be sure that what you have is what is marked on the case, plus you probably paid too much for a premium brand sleeve over an inexpensive substitute.
That's even if you get an inexpensive substitute ... a common form of counterfeit Chinese electrolytic cap is to insert a low value cap inside a large value container, marked as such.
Don't buy electronic components on eBay sourced from China. Transistors, capacitors, ICs are all well known to be counterfeited. Plus, it's usually just as cheap to buy them from Mouser, DigiKey, etc who have documented supply sourcing and the price is usually the same, and often cheaper.
Originally Posted By: Johnny2Bad
Originally Posted By: Merkava_4
That's where the magic of YouTube comes in. I learned that I can discharge the capacitors by laying a screwdriver blade across the terminals. I could've sworn that I heard a fizzing noise when I did that, but it was probably just my imagination.
That's where the magic of YouTube gets people hurt. Capacitors can carry potentially lethal currents, if electrolytic type they do spectacularly explode, which WILL take your eye out, plus the bits are usually pretty [censored] hot, making burns a potential risk. And then there's the corrosive electrolyte all over your equipment.
Never discharge a capacitor by laying a screwdriver blade across the terminals. The safe way involves a resistor across the terminals.
As for Chinese caps, I suggest you just say no. They are by far the most counterfeited components coming out of China, so you cannot be sure that what you have is what is marked on the case, plus you probably paid too much for a premium brand sleeve over an inexpensive substitute.
That's even if you get an inexpensive substitute ... a common form of counterfeit Chinese electrolytic cap is to insert a low value cap inside a large value container, marked as such.
Don't buy electronic components on eBay sourced from China. Transistors, capacitors, ICs are all well known to be counterfeited. Plus, it's usually just as cheap to buy them from Mouser, DigiKey, etc who have documented supply sourcing and the price is usually the same, and often cheaper.
the capacitance and voltages are not that high as to vaporize a good sized screwdriver. but they can vaporize the terminal and throw hot slag in your eye.
When I work on high voltage stuff I verify everything is powered down with my multimeter, wear thick socks and my rubber boots, wear rubber gloves, safety glasses and ear plugs.
Be absolutely sure no-one will switch the breaker back on while you are working (lockout-tagout)
Make the switch and keep everyone clear while reapplying power.
Yes you can wear less PPE but if you're sweaty (remember its hot out there) and get on a line that is hot relative to earth, you will get a good puckering at least. You dont want electricity to flow across your chest. (hand to knee/foot) hand to other hand, etc. That can easily stop your heart.
Most of the things around the AC are earth grounded. Conduit, Switch box, AC metal frame, the ground itself. With 220, either of the Hot legs and run current through you to ground. Leaning on the unit. kneeling on the ground, etc.
Gotta be respectful. It like playing with a rattle snake. the pros make it look easy. the Joes get bit.
When I work on high voltage stuff I verify everything is powered down with my multimeter, wear thick socks and my rubber boots, wear rubber gloves, safety glasses and ear plugs.
Be absolutely sure no-one will switch the breaker back on while you are working (lockout-tagout)
Make the switch and keep everyone clear while reapplying power.
Yes you can wear less PPE but if you're sweaty (remember its hot out there) and get on a line that is hot relative to earth, you will get a good puckering at least. You dont want electricity to flow across your chest. (hand to knee/foot) hand to other hand, etc. That can easily stop your heart.
Most of the things around the AC are earth grounded. Conduit, Switch box, AC metal frame, the ground itself. With 220, either of the Hot legs and run current through you to ground. Leaning on the unit. kneeling on the ground, etc.
Gotta be respectful. It like playing with a rattle snake. the pros make it look easy. the Joes get bit.
Originally Posted By: danez_yoda
Gotta be respectful. It like playing with a rattle snake. the pros make it look easy. the Joes get bit.
Funny you should mention that. The whole time I was taking pictures of the capacitor, there was a gigantic Black Widow spider right next to me.
Gotta be respectful. It like playing with a rattle snake. the pros make it look easy. the Joes get bit.
Funny you should mention that. The whole time I was taking pictures of the capacitor, there was a gigantic Black Widow spider right next to me.
Be careful substituting capacitor types. These AC are in a can and have a Fuse internal so when they try to explode, the fuse cuts the power. I was tempted to use a solid dielectric version but was warned off by their failure mode of catching fire and burining.
Stick with caps made for HVAC use that state they have in internal fuse.
Stick with caps made for HVAC use that state they have in internal fuse.
Originally Posted By: MolaKule
Aerovox
http://www.aerovox.com/IndustrialProductsGroup.aspx caps are the ones I use for replacement. Aerovox caps can be purchased from Grainger.
KEMET: http://www.mouser.com/Search/Refine.aspx?Keyword=Start+run+capacitors
Wow...didn't realize Mouser carried AC motor run caps! Should have checked when mine recently died. I've ordered electronic parts from Mouser for a few decades now....they carry FAR more than they used to.
I'll order some of these back-ups.
Thanks!
Aerovox
http://www.aerovox.com/IndustrialProductsGroup.aspx caps are the ones I use for replacement. Aerovox caps can be purchased from Grainger.
KEMET: http://www.mouser.com/Search/Refine.aspx?Keyword=Start+run+capacitors
Wow...didn't realize Mouser carried AC motor run caps! Should have checked when mine recently died. I've ordered electronic parts from Mouser for a few decades now....they carry FAR more than they used to.
I'll order some of these back-ups.
Thanks!
Originally Posted By: danez_yoda
Be absolutely sure no-one will switch the breaker back on while you are working (lockout-tagout)
Pull the local AC disconnect in addition to turning off the breaker. If you don't have a disconnect on your AC unit, install it in the offseason.
They're standard down here for code compliance and have been for a long time.
Be absolutely sure no-one will switch the breaker back on while you are working (lockout-tagout)
Pull the local AC disconnect in addition to turning off the breaker. If you don't have a disconnect on your AC unit, install it in the offseason.
They're standard down here for code compliance and have been for a long time.
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