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Brian HVAC Guy
Brian HVAC Guy, HVAC Technician
Category: HVAC
Satisfied Customers: 953
Experience:  I have been an HVAC/R mechanic/technician for 30+ years.
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Replacing a start capacitor which is 60+5.0 MicroF +/-6%

Customer Question

replacing a start capacitor which is 60+5.0 MicroF +/-6% 440vac/b.
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: 2 days, but i can get a new one that is 55MicroF. will that work on a 4TON unit?
JA: Did you double-check the thermostat? And what about the unit's filters?
Customer: filters on the return air? thermostat is good & working
JA: Do you plan on doing the work yourself?
Customer: my AC guy is coming by to install the new one today & he does the maintenace on my house unit as well as my condo too. been using him for about 5 years.
JA: Anything else we should know to help you best?
Customer: so unlikely that the compressor is bad?
Submitted: 1 year ago.
Category: HVAC
Expert:  Brian HVAC Guy replied 1 year ago.

Hi I'm Brian and I'm here to help!

Replacing a 60 Mfd cap with a 55 Mfd cap is not recommended. The tolerance for run capacitors is +/- 5% so 55 is below that tolerance. It may work in an emergency or interim situation until you can get the proper size capacitor. If the run cap is definitely bad, there is a good chance your compressor is ok. That's not an absolute though.

Let me know if you have further questions on this subject. Otherwise, please remember to rate before leaving (3 stars or higher please!). Bonuses are always appreciated! And remember, follow up questions about this topic are free even after rating. Just post a new reply on this same question and I'll be notified. Thanks for allowing me to help and thanks for using Just Answer!

Thank you,

Customer: replied 1 year ago.
the fan motor runs normal, but the compressor does not kick in. The capacitor is not humped up on the top, it is flat.
Expert:  Brian HVAC Guy replied 1 year ago.

Capacitors don't necessarily have to be bulging to have failed. They can fail without bulging or they can get weak as well. If your compressor is not starting, it could be a weak capacitor or your compressor may be getting harder to start with age. The first step is to ensure the compressor is getting full voltage and there are no burnt wires or burnt contact points. The second step is capacitor check/replacement and then you can go further with the addition of a boosting capacitor typically called a 'hard start kit'. Your hvac guy will probably follow this procedure. The worst case scenario it that your compressor is seized up and there's nothing that can be done there except a compressor replacement.