Condenser Motor Or Capacitor?

[emailaddress]

About two years ago the capacitor on our external AC condenser failed and was replaced. The unit has ran fine since then. Last night the fan stopped and the unit began making more noise.

Poking the fan blades showed they spin quite freely. Am I right in assuming that since the unit was still making noise that it can't be a relay (was dark, but if there were any it looked like only one in the unit), that the only thing remaining is either this 2 year old capacitor or the motor itself?

Motor is about 15 years old, looks like a typical GE 220V 1.4A 1/4 HP. Opening it up it looks fine inside, though a problem in the windings might not be something I could see. I have basic electronics skills, is there a way to test the integrity of the motor or reasonably run it outside the condenser?

The run capacitor on these is about 5uF, or at least that's the motor spec'd value. Will this type of capacitor read normally out of circuit with a capacitance meter, and if it's value was within tolerance can the capacitor then be assumed in good operable condition?

Am I correct in assuming that if I momentarily turn the AC on without the fan hooked up at all (being sure to turn it off again before the compressor overheats due to no airflow) that if I measure the expected

220V at the motor hookup points, this is another indication it has to be either the capacitor or motor itself? With the motor open, with the armature removed from the stator, between three wires I'm getting resistance readings of 28 Ohm, 56Ohm, 84 Ohm. These look right for a typical 1 phase condenser motor, being all three multiples of 28 Ohm, correct?

The last capacitor was obviously, visually bad as indicated by it bulging. The new (2 year old) one looks mint still. Does anyone have further ideas for troubleshooting this besides swapping in a new motor and/or capacitor, and which do you think is the cause?

[Noon-Air]

yup the system is getting on in age and close to the end of its design life cycle. Were it me, I would probably install a new motor and capacitor, then start putting a bunch of money in the bank to replace the system.

[emailaddress]

Thanks for your reply. It seems my multimeter capacitance setting doesn't range up to 45uF, and I wasn't even sure if it was working properly as it didn't read the 5uF on the dual capacitor, so I dug out another meter and checked a different run capacitor I had lying around. I also found a short on the dual cap's fan motor run and common terminals so it looks like a safe bet the capacitor is shot.

Do you/anyone know if there are significant differences in quality among the various capacitors out there? The first one lasted 13 years, AFAIK, and this replacement only 2 years. I did a web search and found the exact same cap selling online for $17 so it's definitely one of the cheapest of it's kind.

I'd just rather spend more if it'll make a difference then not have to fool with it again for more than a couple years. It's value is

45/5uF, 440V, dual round can (though oval would work, I'm not /that/ picky). Then again it's still summer, 90F+ here so whatever I can find locally is better than waiting. I'll wait-n-see on the fan motor though, think I sourced a replacement if it comes to that.

[Noon-Air]

Thanks for your reply. It seems my multimeter capacitance setting doesn't range up to 45uF, and I wasn't even sure if it was working properly as it didn't read the 5uF on the dual capacitor, so I dug out another meter and checked a different run capacitor I had lying around. I also found a short on the dual cap's fan motor run and common terminals so it looks like a safe bet the capacitor is shot.

Do you/anyone know if there are significant differences in quality among the various capacitors out there? The first one lasted 13 years, AFAIK, and this replacement only 2 years. I did a web search and found the exact same cap selling online for $17 so it's definitely one of the cheapest of it's kind.

I'd just rather spend more if it'll make a difference then not have to fool with it again for more than a couple years. It's value is

45/5uF, 440V, dual round can (though oval would work, I'm not /that/ picky). Then again it's still summer, 90F+ here so whatever I can find locally is better than waiting. I'll wait-n-see on the fan motor though, think I sourced a replacement if it comes to that.

Try a Rheem/RUUD part number 43-25133-16. I have never had one of those fail.

[Stormin Mormon]

Hmm. 45/5? I just bought a couple of those last week. I was cleaning the condensor (sorry boys) on a Trane unit, and that's the size it took. Figured I ought to have one available for the next customer who needed one. How did things work out, now that you have the new cap installed?

[emailaddress]

I didn't get the new one installed yet. I'd mentioned a different cap I had but it only served to reassure me that my multimeter's capacitance test function still worked, that other cap was too low a value to use.

Since it's Labor day today, I'm waiting till tomorrow to get the cap locally.

[KJPRO]

I highly suggest that you make a call to your favorite HVAC company, as it is painfully obvious that you *don't* have basic electrical skills!

[Zyp]

"With the motor open, with the armature removed from the stator, between three wires I'm getting resistance readings of 28 Ohm, 56Ohm, 84 Ohm. These look right for a typical 1 phase condenser motor, being all three multiples of 28 Ohm, correct?"

And you took the motor apart because??????

[Stormin Mormon]

He's an engineer.

[SilverWolf]

Sounds like the condenser fan motor is defective Replace the fan motor :-)

[emailaddress]

Because if I saw signs of overheating, if the meter showed the thermal breaker was open, or if I wanted to lube the rear sleeve bearing, they're all a heck of a lot easier with it open (impossible when not).

[emailaddress]

quoted text -

Thanks for trolling by. My favored HVAC company stuck me with a bill in excess of $200 for a $17 capacitor that takes 5-10 minutes to install and then failed 2 years later. If you'd call them again, go right ahead.

[emailaddress]

ide quoted text -

I've opened and relubed all the fans in our HVAC system. Two were clearly squealing and would have failed if I had not, but they are still running fine over 4 years later.

Anyway, made the trip to the local supplier today and picked up a $12 capacitor. That's all it took, fan/motor works fine as does the whole system now. I should've bought two caps while I was there, put one in a drawer as a backup like I do with spare batteries.

One thing I hadn't realized is about 3/4ths of the suppliers around here won't do business with an individual, you have to have a business account with them. Even the place that sold the cap to me had a sign next to their door stating as much. Seems like a shady industry to me, refusing to sell a $12 part so everyone ends up paying over ten times as much. Actually I did work in the HVAC industry years ago doing new residential rough-ins but never dealt with the repair parts/ cost side of the business.

Anyway thanks to everyone for their replies.

[What a maroon]

Do you have any clue why a capacitor and service call cost "in excess of 200.00"? I am sure you don't or you would not keep making assinine statements. We are running a business, not a charity asshole. Now go the f*ck away.

[Zyp]

What a maroon;

Don't you know any other adverbs or nouns besides four letters? You're such a jerk you're pathetic.

[emailaddress]

You feel that being offensive somehow justifies over $200 to drive 5 miles round-trip and do 5 minutes of work? Sorry, but most white collar professionals don't make that nor should you in my opinion, but if you can make a living doing that, it's really up to the customer isn't it?

I for one am a customer that has decided not to pay that much so if you wanted to have my business you'd lower the rate or lose a customer. It's really up to you, and to me too!

[Noon-Air]

You feel that being offensive somehow justifies over $200 to drive 5 miles round-trip and do 5 minutes of work? Sorry, but most white collar professionals don't make that nor should you in my opinion, but if you can make a living doing that, it's really up to the customer isn't it?

I for one am a customer that has decided not to pay that much so if you wanted to have my business you'd lower the rate or lose a customer. It's really up to you, and to me too!

------------

So according to you, we're supposed to get our trucks, insurance, fuel, maintenance, repairs, tires, brakes, etc. all for free, oh and then there is the small matter of our time behind the windshield, then the time while we are there, and the education, training, knowledge, and experience to know how to find the problem, then correct it with parts inventory that we carry on the truck. Most of us don't have a store front, otherwise we would have to charge for that additional overhead too. Let me give you some figures to mull over... assuming that I brought in $130,000 gross reciepts, and after all of the costs and expenses are paid, they *might* be $40,000 left over to pay salaries after federal and state taxes, then paying my salary, of which the feds and state get another 35%, which leaves me with only $26,000 to live on(and I have 2 daughters in college).... and thats without holding out and for *profit* to re-invest in the company.

That being said... without knowing where you are, the price you paid would be about right for small town, rural south Mississippi.

Now... I already gave you the part number for a quality replacement, don't let the door hit you inna ass on the way out.

[Noon-Air]

I've opened and relubed all the fans in our HVAC system. Two were clearly squealing and would have failed if I had not, but they are still running fine over 4 years later.

Anyway, made the trip to the local supplier today and picked up a $12 capacitor. That's all it took, fan/motor works fine as does the whole system now. I should've bought two caps while I was there, put one in a drawer as a backup like I do with spare batteries.

One thing I hadn't realized is about 3/4ths of the suppliers around here won't do business with an individual, you have to have a business account with them. Even the place that sold the cap to me had a sign next to their door stating as much. Seems like a shady industry to me, refusing to sell a $12 part so everyone ends up paying over ten times as much. Actually I did work in the HVAC industry years ago doing new residential rough-ins but never dealt with the repair parts/ cost side of the business.

Anyway thanks to everyone for their replies.

--------------

Here is a *CLUE*.... HVAC contractor is a *RETAIL* business..... same as a grocery store or a mechanics garage, or most any other business. Do you buy your groceries wholesale?? I think not, nor does your mechanic sell wholesale. People are in business to provide for their families and maybe even make a meager profit to reinvest in their companies. Get it?? Got it?? Good... now please go away

[emailaddress]

Regardless of all that, you are ignoring that other professionals like doctors will spent more time, even have a staff and place of business, and still manage to charge less.

I'm not saying you aren't entitled to a decent living. I'm saying some repairs are not worth the price often asked even if others are.

I live in a suburb near a major metropolitan area, there are about 25 HVAC businesses within 10 miles and possibly dozens more independant individuals. Maybe I should have called a dozen and picked based on price.

Such nice people there are on usenet. Yes you gave the part number, now tell us how you can not be busy enough to be posting on the internet if you are in the US, at the tail end of the peak AC season. I think the answer to your monetary figures above is do more advertising and get more jobs, not charge more per job. Maybe I'm wrong but if you have time to post on the internet in the middle of the day, you're not simultaneously doing any repairs.

[KJPRO]

You feel that being offensive somehow justifies over $200 to drive 5 miles round-trip and do 5 minutes of work? Sorry, but most white collar professionals don't make that nor should you in my opinion, but if you can make a living doing that, it's really up to the customer isn't it?

I for one am a customer that has decided not to pay that much so if you wanted to have my business you'd lower the rate or lose a customer. It's really up to you, and to me too!

I'd rather lose a cheap ass customer than to go under for not charging enough to keep the truck on the road! Or would you rather someone lower their quality of work and send out a rookie, that will inform you that the complete system needs to be replaced? When in fact, if the technician had been properly trained (recieving a proper wage) would have fixed it?