Recent Topics
It's AMSOILŪ, not Amsoil
by Rat407
06/25/18 06:39 AM
VW Passat 2007
by madRiver
06/25/18 06:18 AM
Review: CVJ Remanufactured CV Axles
by The Critic
06/25/18 03:40 AM
Towing without 85w140?
by OilFilters
06/25/18 03:07 AM
2015 VW GTI autobahn oil questions
by Skyalbo
06/24/18 11:28 PM
Corrosion in the garage - salt or humidity?
by Kurtatron
06/24/18 11:13 PM
Darn dogs
by AZjeff
06/24/18 10:21 PM
New GC?
by Bullwinkle007
06/24/18 10:04 PM
The guy with the plexiglass head on you tube
by andyd
06/24/18 09:21 PM
'07 Pacifica Timing Belt Replacement success
by 92saturnsl2
06/24/18 09:10 PM
SAE 90 v 85/140
by Knuckle078
06/24/18 09:10 PM
Mobil 1 5W30-HM 5,011 mi, 1999 Ford Escort
by WA1DH
06/24/18 08:45 PM
Schaeffer's oil reviews on Amazon
by zfasts03
06/24/18 07:41 PM
Decent MP3 player
by Ed_T
06/24/18 07:08 PM
Letgo
by Donald
06/24/18 06:52 PM
Tire buying advice
by supton
06/24/18 06:23 PM
Two versions of M1 5w30 ESP now?
by Patman
06/24/18 06:21 PM
No older cars in New York State?
by Oldtom
06/24/18 06:19 PM
2009 Taurus strut mount noise
by terry274
06/24/18 04:38 PM
A3/B3 vs A3/B4, big difference or irrelevant?
by FordCapriDriver
06/24/18 03:36 PM
Newest Members
dhy808, ROD_Z, lozpxs, danthemanx07, FunktasticLucky
65319 Registered Users
Who's Online
99 registered (2004tdigls, 2002 Maxima SE, andyd, alcyon, 1foxracing, 15 invisible), 1424 Guests and 63 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
65319 Members
67 Forums
285959 Topics
4772023 Posts

Max Online: 3590 @ 01/24/17 08:07 PM
Donate to BITOG
Page 1 of 3 1 2 3 >
Topic Options
#4478722 - 08/04/17 05:20 AM Residential A/C Capacitors
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
I watched this video and the guy said that A/C condensing unit capacitors are a wear item and eventually they all fail. When the capacitor fails, your compressor and the condensing unit fan will not start. You don't want them failing on the weekend because the retail home centers will not have them. He recommends everybody should have a spare as a backup. I'm trying to figure out why my condensing unit has two capacitors plus a starter. Usually all you need is one capacitor and starter as illustrated on the starter itself (see 3rd picture). So I'm wondering if I should keep an extra genteq capacitor on hand, or an extra of all three.

Goodman Condensing Unit Model CKL30-1F
genteq 25L502 440 VAC capacitor
Mars2 12905 370 VAC capacitor
Supco SuperBoost SPP6 hard start kit

1. https://flic.kr/p/W8DxQQ
2. https://flic.kr/p/W8DxHf
3. https://flic.kr/p/Xpv8nV

Top
#4478726 - 08/04/17 05:33 AM Re: Residential A/C Capacitors [Re: Merkava_4]
2015_PSD Offline


Registered: 09/26/10
Posts: 7248
Loc: SE Texas
In 53 years of having to use AC systems in the south (which means they run nearly year-round) I can count on three fingers the number of times a capacitor has failed. My point is although you are correct that a normal retail place will not have a capacitor, the odds of it actually failing are quite low.
_________________________
2018 MB AMG GLC43 3.0L Coupe - M1 0W-40/OEM
2018 MB C300 2.0L - M1 0W-40/OEM
2015 F-250 6.7L PS Diesel - Delo 5W-40/CQ Blue
2014 Explorer 3.5L Limited - M1 AFE 0W-20/FU

Top
#4478728 - 08/04/17 05:41 AM Re: Residential A/C Capacitors [Re: 2015_PSD]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
2015_PSD,

I've had it happen twice since 2004 when I first got the new condensing unit.

Top
#4478729 - 08/04/17 05:45 AM Re: Residential A/C Capacitors [Re: Merkava_4]
JC1 Offline


Registered: 11/29/08
Posts: 3019
Loc: Oshawa, Ontario Canada
I had a capacitor fail on mine last year. Ac unit was installed in 2003.
_________________________
2015 Grand Caravan SXT Plus 5w-20 PPPP/Wix Filter
1997 Honda Civic CX 5w-30 PPPP/Mahle Filter

Top
#4478735 - 08/04/17 05:52 AM Re: Residential A/C Capacitors [Re: JC1]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
The guy in the video said they last 60,000 hours. There's 8,640 hours in a year.

Top
#4478741 - 08/04/17 06:05 AM Re: Residential A/C Capacitors [Re: Merkava_4]
SteveSRT8 Offline


Registered: 10/10/08
Posts: 18958
Loc: Sunny Florida
Carriers are solid units IMO. Our experience with the old one here was amazing, the thing just wouldn't stop.

But around these parts lightning is a significant threat. Poor quality power and huge surges don't do anything to help. Caps do occasionally fail...
_________________________
"In a democracy, dissent is an act of faith."
J. William Fulbright
Best ET-12.79 @ 111 mph
4340 pounds, Street tires
Just like we go to Publix

Top
#4478749 - 08/04/17 06:24 AM Re: Residential A/C Capacitors [Re: Merkava_4]
Kruse Offline


Registered: 10/05/05
Posts: 4298
Loc: Kansas
The local HVAC store sells caps, their markup included, for $10-20.
If it makes you sleep better, go ahead and buy one, but odds are you won't ever need it.

Top
#4478753 - 08/04/17 06:27 AM Re: Residential A/C Capacitors [Re: Merkava_4]
65f100 Offline


Registered: 09/18/11
Posts: 105
Loc: Oklahoma
Get a test meter that can check the capacitor versus the rating marked on the side yearly (unplug the power and discharge the capacitor before removing!). If it is out of spec, replace it before it fails. Don't buy Chinese run capacitors. Pay the extra and get made in USA.

Top
#4478759 - 08/04/17 06:34 AM Re: Residential A/C Capacitors [Re: Merkava_4]
tdi-rick Offline


Registered: 02/02/04
Posts: 1847
Loc: the antipodes
Originally Posted By: Merkava_4
I watched this video and the guy said that A/C condensing unit capacitors are a wear item and eventually they all fail. When the capacitor fails, your compressor and the condensing unit fan will not start. You don't want them failing on the weekend because the retail home centers will not have them. He recommends everybody should have a spare as a backup. I'm trying to figure out why my condensing unit has two capacitors plus a starter. Usually all you need is one capacitor and starter as illustrated on the starter itself (see 3rd picture). So I'm wondering if I should keep an extra genteq capacitor on hand, or an extra of all three.

Goodman Condensing Unit Model CKL30-1F
genteq 25L502 440 VAC capacitor
Mars2 12905 370 VAC capacitor
Supco SuperBoost SPP6 hard start kit

1. https://flic.kr/p/W8DxQQ
2. https://flic.kr/p/W8DxHf
3. https://flic.kr/p/Xpv8nV


I can't see how it's wired but it could be one of two things.

1) Two of the run caps are together to get the correct capacitance, either in series or parallel.
I've done this heaps of times when I don't have the right one with me.

2) The 5 mic run cap is for the condenser fan motor.

Back before DC variable speed inverter driven compressors became the most common, PSC (permanently split capacitor) style compressors ruled on single phase installations.
Run capacitors would be the most common replacement parts.
_________________________
Land Rover.
Helping put oil back in the ground for 60 years.
You can't get any greener than that......

Top
#4478763 - 08/04/17 06:38 AM Re: Residential A/C Capacitors [Re: Merkava_4]
bullwinkle Offline


Registered: 10/09/04
Posts: 7673
Loc: Cincinnati, OH, USA
Run caps tend to dry out, lose their capacitance, & eventually open, causing high run amps. They don't need to be discharged (unlike a start capacitor), but you'll need a meter with a microfarad scale to test them. Or just replace it & check the running amperage of the compressor or fan motor & see if it drops. If you have a hard start kit, then there can also be a start relay, which should always be replaced with the start cap.


Edited by bullwinkle (08/04/17 06:40 AM)
_________________________
06 Ram 3500 CTD 4X4(FG Venturi), 93 GMC C3500 6.2, 89 F-450 7.3, 98 XJ 4.0(XG8A), 05 xB(XG3600), 15 Transit 3.7, 03 Merc Grand Marquis 4.6 2V(XG2)

Top
#4478764 - 08/04/17 06:40 AM Re: Residential A/C Capacitors [Re: Merkava_4]
laserred96gt Offline


Registered: 03/03/13
Posts: 890
Loc: Florida
Originally your unit had only one dual run capacitor but seems like they have replaced the fan motor which normally gets a new capacitor (which is the little one). Then someone replaced your dual cap with a single cap for your compressor and installed a hard start kit ( which is your black gismo ).

I've seen 30 year old units still running on their original capacitor meanwhile the capacitor on my 3 year old unit went bad about a month ago, ( replaced under warranty).
_________________________
96 Mustang GT: Castrol Edge 5w50
04 E-150, 4.6, 226K, PU 10W30.
11 Camry 2.5, 60K, Castrol Edge 0W20.

Top
#4478766 - 08/04/17 06:40 AM Re: Residential A/C Capacitors [Re: tdi-rick]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
Originally Posted By: tdi-rick
2) The 5 mic run cap is for the condenser fan motor.


Is that the short oval capacitor?

Top
#4478771 - 08/04/17 06:46 AM Re: Residential A/C Capacitors [Re: Merkava_4]
2015_PSD Offline


Registered: 09/26/10
Posts: 7248
Loc: SE Texas
Originally Posted By: Merkava_4
2015_PSD,

I've had it happen twice since 2004 when I first got the new condensing unit.
You have more going on there than just a bad/weak/poor quality capacitor. One thing that I have seen happen fairly frequently is sometimes the technicians do not have the correct sized capacitors when they come out and make the repair and put an undersized capacitor in place that will work but only for a shorter period of time.
_________________________
2018 MB AMG GLC43 3.0L Coupe - M1 0W-40/OEM
2018 MB C300 2.0L - M1 0W-40/OEM
2015 F-250 6.7L PS Diesel - Delo 5W-40/CQ Blue
2014 Explorer 3.5L Limited - M1 AFE 0W-20/FU

Top
#4478785 - 08/04/17 07:02 AM Re: Residential A/C Capacitors [Re: Merkava_4]
danez_yoda Offline


Registered: 07/18/09
Posts: 471
Loc: texas
This is good advice,

There are two types of capacitors commonly used. 1 is a combination cap with three terminals. It is a single large can that has both the compressor cap and the fan cal. Its usually marked something like 30uF and 5uf (Values vary depending on the unit). The three terminals are marked Com, HERM and Fan. Herm is the compressor since it is hermatically sealed.

You can also buy separate caps for the fan and herm and wire them together.

The "kickstarter" cap is typically optional and only needed in special situations. Did an AC tech add that during a service call? These are commonly a profit item for them. smirk

The capacitors of old has PCBs (chemincal not electronics) in them that was banned in the late 90s. These caps lasted forever. The newer caps are eco friendly and have a higher failure rate over time at temperature.

I had the same thing happen to my 2003 Carrier. Around 2008 the unit stopped and the fan on top would not turn and the HERM would humm loudly. I killed the power at the breaker and took a look (I and an EE by the way). The AC cap had its top domed out like a beer can left in the sun and when I looked it up on the internet they showed it built up internal pressure and broke a fuse when the top swelled so it wouldn't explode.

https://www.youtube.com/watch?v=mB89knyysFE


Of course this was a Sunday on a weekend with a Monday holiday (Labor day). and it was in the high 90s. I limped by with a window unit in a single "cool room" until Tuesday.

I replaced it with a Dayton from Granger (only place I could get one that day) for ~$50 and was back in business for about a year and a half. Then it popped. frown.


I also bought a el-cheapo backup from ebay for $30 as a backup. So it went into service while I ordered a Genteq cap and the final backup.
The Genteq cap was swapped in when it arrived, and was in service until 2016 when the evaporator developed a hole and I upgraded to a higher efficiency unit. 16 seer vs 12. It showed a noticeable decrease in energy usage but not dramatically so. I think the previous unit was not "hurt" by sitting there humming for a few hours before I found the capacitor problem.


There is also one in your furnace fan. Its is also about 5uF. Mine had degraded down to 3uF and the fan was struggling to start. It has a loud hum on startup. AC tech said the cap was bad and they cost $150/each to replace + service fee. I bought a Genteq for $20 off amazon and figured out the two prongs myself.


*****

Note these are high (lethal) voltage capacitors and connected to high voltage service lines. If you don't know the safety aspects of dealing with a few hundred voltages and charge storing components like capacitors, you should have a qualified tech do it for you. Saving a few dollars is not worth your risking injury or death

******

Top
#4478791 - 08/04/17 07:10 AM Re: Residential A/C Capacitors [Re: danez_yoda]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
Originally Posted By: danez_yoda
Note these are high (lethal) voltage capacitors and connected to high voltage service lines. If you don't know the safety aspects of dealing with a few hundred voltages and charge storing components like capacitors, you should have a qualified tech do it for you. Saving a few dollars is not worth your risking injury or death.


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.

















Top
Page 1 of 3 1 2 3 >