Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

[Evil Lurker]

Yesterday my central unit died. The blower fan would still work but the compressor pump and external condenser fan refused to start.. the would just sit there and buzz. I had been noticing for months that the unit was having a hard time starting... the lights in the house would dim whenever the compressor kicked in.

After tearing into the unit and checking voltages at various test points with them all appearing good thats when on a whim I attempted to manually spin the fan... it started. Hmmmmmm... that almost sounds like a start/run capacitor. Sure as shit when I took a close look at the Hongkongflyapart 45/5uf dual run cap the ends were bulging. So after a trip to the scrap yard I located a 35/5uf cap off a similar unit and put it in mine hoping to bring the unit back to life. Sure as heck it fired right up. After thinking about it, there is no tellings how much wear this defective cap put on my compressor and how much it has cost me in increased electricity costs.

Bad caps on a less than 3 year old central unit... who woulda thunk it?

[ben7]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Hey, its made in china! what else to expect? xD
Our AC unit has been going good for over 10 years now

-Ben

P.S. got any pics?

[Agent24]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

P.S. got any pics?

[Hemingray]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Same situation on our 10 y/o Trane unit, S/R cap was bulging out, causing the same problem. Replaced it, and all is good again

[Krankshaft]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Good thing you caught it in time.

Most A/C units manufactured nowadays are inverter units the inverters are the Achilles heel of the system and are also usually poorly ventilated which doesn't help the caps. Not uncommon for these units to start acting up 3-5 years down the line way sooner in salty environments. Of course this didn't happen with the older units that used a thermostat for an On/Off signal to the compressor instead of PWM. More complexity in the name of "energy savings".

[brethin]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Yesterday my central unit died. The blower fan would still work but the compressor pump and external condenser fan refused to start.. the would just sit there and buzz. I had been noticing for months that the unit was having a hard time starting... the lights in the house would dim whenever the compressor kicked in.

After tearing into the unit and checking voltages at various test points with them all appearing good thats when on a whim I attempted to manually spin the fan... it started. Hmmmmmm... that almost sounds like a start/run capacitor. Sure as shit when I took a close look at the Hongkongflyapart 45/5uf dual run cap the ends were bulging. So after a trip to the scrap yard I located a 35/5uf cap off a similar unit and put it in mine hoping to bring the unit back to life. Sure as heck it fired right up. After thinking about it, there is no tellings how much wear this defective cap put on my compressor and how much it has cost me in increased electricity costs.

Bad caps on a less than 3 year old central unit... who woulda thunk it?

If you have HVAC in your home you really suck trying to say your broke and are poor. Poor means you use a broom to sweep the carpet if your lucky enough to have carpet in the house.

Seems to be alot of these types of poeple on Badcaps saying "Im so poor but ingnore my Rich person Item problems"

[PeteS in CA]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

If you have HVAC in your home you really suck trying to say your broke and are poor. Poor means you use a broom to sweep the carpet if your lucky enough to have carpet in the house.

Seems to be alot of these types of poeple on Badcaps saying "Im so poor but ingnore my Rich person Item problems"

OK ... I'm aware of the First-World Problems --- Third-World Problems social commentary, and do not regard it as BS. But where in EL's post starting this thread did he say anything remotely resembling, "your broke and are poor" or "Im so poor but ingnore my Rich person Item problems"? I mean, I did see his comment, "there is no tellings how much wear this defective cap put on my compressor and how much it has cost me in increased electricity costs," but I would see that as wanting to use his $$ well and take care of the things he has.

Back on-topic, we also experienced a motor start capacitor failure in our AC last year, the unit being but 7 years old. Not sure of the brand and I'm not currently at home.

[Toasty]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

@PeteS - https://www.badcaps.net/forum/showthread.php?t=19496 - post #2

[inuyasha.rules]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Im broke too, not so broke that im eating out of dumpster, and I have central air and own my own house. Have some compassion. Ever hear about this thing called the economy crashing?

[RJARRRPCGP]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

Most A/C units manufactured nowadays are inverter units the inverters are the Achilles heel of the system and are also usually poorly ventilated which doesn't help the caps. Not uncommon for these units to start acting up 3-5 years down the line way sooner in salty environments.

Are you telling me that they're like CFL LCDs? (Especially 2006 LCDs, which seem to have bad caps more than other years.)

[mazda8616]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

hey guys last year same problem told by parts house extrem heat just like computers will zap even new caps / also even if it is a bigger problem make tripley sure when buying ac parts beware of the one size fits all parts house / bad experience with a condenser motor . last sorry for the wind but if you need online ac trouble shooting send me a message and i will be glad to help you

[paul_h]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

I repair a/cs, and this is the most common break down. I replace at least 4 per week in summer.
Especially those 2 way caps that do the fan and the compressor. Mostly LG have them here, and lucky to last 5 years, but carrier have them too.

Most chinese and japanese fixed speed a/cs we have here always have separate caps for fan and compressor.
But no matter what brand it is, if it has a chinese capacitor (in vege oil), lucky to last 5 years. Every no name brand has them, but so do some expensive premium brands too.

But common to see 10 year old or older japanese made capacitors still running fine. And even the nasty old ones in 20 y/o plus air cons

It's no just electrolytic caps that have got worse over the years, 400v start/run-PSC caps for motors have got worse too.

Edit:

Good thing you caught it in time.

Most A/C units manufactured nowadays are inverter units the inverters are the Achilles heel of the system and are also usually poorly ventilated which doesn't help the caps. Not uncommon for these units to start acting up 3-5 years down the line way sooner in salty environments. Of course this didn't happen with the older units that used a thermostat for an On/Off signal to the compressor instead of PWM. More complexity in the name of "energy savings".

I think the OP is talking about non inverter a/cs, the motors are mains PSC motors with a start and run winding. Fixed speed, conventional motors. They have a mains cap across the windings for motor torque. Those 400v AC caps are crap now and the most common cause of failure now they are cheaper and chinese made.

Edit: BTW, I've never had a bad cap on an inverter a/c PCB, I have had a few on indoor control PCBs, but that happens with non inverters too (and more often), but never anything on an outdoor PCB, except for the while thing going bang because the compressor is shorted out. Diode bridges are the most common outdoor inverter PCB fault though.

[japlytic]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

In a portable air conditioner (Nobo Cool/Polo Cool) from a client of mine was a bad 3uF 450VAC motor starting capacitor, which was causing the motor connected to it to make a "ticking" sound, like it was trying to start up.
I found this bad capacitor when I was checking the AC capacitors for uF value (after discharging them).

[larrymoencurly]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

I looked at the White-Rodgers defrost board/ fan controller for my Rheem packaged heatpump and noticed no L-C line filter, despite the board having a microprocessor. How do they get away with digital in such an electrically noisy environment? I couldn't find an L-C filter elsewhere, and the wiring diagram didn't show any. BTW a couple of copper traces were lifted, and I don't think it was from vibration.

Most of the problems I've had with central A/C have been with the electronic boards. The defrost board of the old Rheem developed a bad relay and was replaced with a homemade board that was a copy, only I used Radio Shack relays. The fan controller of the ICP Heil heatpump that replaced it was changed 4 times under warranty and finally by a homemade board that ran fine for 3 years until I put back the original board to hide the evidence of tampering so I could get the failed reversing valve replaced under warranty.

[Logistics]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

If you have HVAC in your home you really suck trying to say your broke and are poor. Poor means you use a broom to sweep the carpet if your lucky enough to have carpet in the house.

Seems to be alot of these types of poeple on Badcaps saying "Im so poor but ingnore my Rich person Item problems"

You should know better than to post this.

[PeteS in CA]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

I'm not necroing this thread to be annoying, but I remembered it - the reason which will be obvious - specifically, having made this post. Guess what part only lasted about 2 years?! And in San Jose, CA, which doesn't exactly have an extreme climate! A week ago we were a week into some 10 days of temps in the low-upper 90s, but for some folks here, that's the normal everyday summer temperature. And guess where our 2YO CRAPacitor was made?

[ben7]

Re: Bad caps nearly killed my central HVAC unit.. and they have costed me $$$'s

I'm not necroing this thread to be annoying, but I remembered it - the reason which will be obvious - specifically, having made this post. Guess what part only lasted about 2 years?! And in San Jose, CA, which doesn't exactly have an extreme climate! A week ago we were a week into some 10 days of temps in the low-upper 90s, but for some folks here, that's the normal everyday summer temperature. And guess where our 2YO CRAPacitor was made?

Pics, or it didn't happen!