Ask Experts Questions for FREE Help !
Ask
    gsmartie's Avatar
    gsmartie Posts: 1, Reputation: 1
    New Member
    		  
    #1

    Aug 8, 2010, 04:54 AM
    AC Compressor Loud Buzz Noise at Start
    Hello. Question, my AC unit was serviced less than two weeks ago. The capacitor had to be replaced since the unit wouldn't start up. Ever since the contractor came out, the unit starts up with a loud buzzing noise. It takes a few seconds and then it goes back to its usual humming sound. The unit is 3 years old.
    The tech replaced an old 60 10 capacitor. Didn't have the right one with him and made one out of three he had in his car.
    Two days later they came out to recheck and make sure everything was fine. I had called because the noise was loud at start up. The tech installed a starter kit. It didn't help.
    What could be causing the 1-2 seconds of loud noise at start up all of a sudden? It only does it if the unit has been idle for a while.
    Could it be the "combination of capacitors" I have in there now? He wired them properly, second take who came the next day didn't see anything wrong with it and said that as long as he 60 are connected to the compressor and 10 to the fan it's fine.
    I have the impression the motor is powered up in stages when I hear the vibration and loud sound and once it gets enough electricity it runs fine.
    Thank you.
    hvac1000's Avatar
    hvac1000 Posts: 14,540, Reputation: 435
    Heating & Air Conditioning Expert
    		  
    #2

    Aug 8, 2010, 11:28 AM

    If he added refrigerant to the system and you have a flow rater or cap tube expanding device on your indoor coil it could be a overcharge condition which would flood back for a few seconds on start-up. Seen this many times. Also the combo of the capacitors might not be exactly correct causing the compressor to strain on start up. These are just guesses on my part since I am not there to test it.
    Attached Images
     
    mymyri's Avatar
    mymyri Posts: 1, Reputation: 1
    New Member
    		  
    #3

    Jul 23, 2012, 04:40 PM
    Compressor has rattling noise coming , like metal balls spinning around. What should ido?
Not your question? Ask your question View similar questions
 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Split unit RHEEM ac compressor fan motor makes loud noise & cuts off then on, [ 2 Answers ]

New1/3hp 1075 208vac ao smith

Loud buzz in CB panel when A/C turns on [ 4 Answers ]

Each time my central A/C turns on, there is a loud buzz for less than a second from the CB panel, then the A/C comes on and runs just fine. The A/C is a new unit, but I recall hearing the buzz with my old unit for many years and thought it was related to that. I have 200A service but the panel...

Repetitive buzz from my compressor [ 1 Answers ]

Help. I hear a buzz every 45 seconds or so. The unit seems to be working, but blowing not as cold. Thanks,

Loud buzz when central A/C starts [ 1 Answers ]

Each time my central A/C starts, there is a loud buzz for 1 second. The unit is new and works fine - just wondering if this is unusual. I've been told its probably the relay sending power out to the outside condenser. Anyone else familiar with this?

View more questions Search