Question1998 Honda civic new compressor and condenser.I picked it up from repair shop last week ac did no get cold. I noticed a humming noise coming from the evaporator each time I accelerate. Low side line cool high side line hot.
I am trying to get a ballpark diagnosis so when I return the car to the shop, the don't give a lame excuse. The shop has had my car three weeks and cant fix it properly. thank you
AnswerCharles,
If what you are looking for is a ballpark, I may be able to help with the information I have, but to be able to tell anything for certain, I would definately need more info.
One source for a "humming" noise coming from the evaporator would simply be the refrigerant flowing through the metering device into the evaporator. You may just be hearing the refrigerant as it slows down and drops the pressure. But it should not be humming. It could be that when they replaced the compressor, they didn't replace the orifice tube. It may have metal shavings or something foreign restricting the flow through the mesh screen on it causing this noise.
Is your fan blowing as it should? You may also be hearing an electrical hum, sometimes heard before your blower motor goes bad. This is caused by the poor contact being made by the brushes to the armature inside the motor itself. Would this cause it not to get cold? Not so much as it would be more noticable that the air is not blowing as it should.
Other than these two items, there is really nothing else that would cause a hum from inside the cab of the vehicle. And yes, they would be affected by the acceleration. The faster the engine turns=the faster the compressor turns=the faster the refrigerant flows through the system. And the faster the engine turns=faster the alternator turns=slightly more voltage going to your fan motor.
But I would be a bit wary of this shop. There is no reason other than a huge workload that anything inside the A/C should take 3 weeks to diagnose and repair, unless they simply haveno clue about how an a/c system works. Which, unfortunately there are many shops out there that claim to service he A/C but do not know anything about how it operates. All they know to do right is to recover and charge the system. I feel your pain. Which brings me to the next question... what made them diagnose that your compressor was faulty in the first place, and why did that entail replacing the condensor also? They probably said something about metal shavings getting into the condensor and you should worry about it traveling through the system and hurting your compressor again. Yes that is true, but it is much easier and cheaper to flush the condensor with a flushing agent and nitrogen than to replace the coil itself.
Ok, I will step down from the soapbox now. I am sorry that you are having this experience, and please do not base your opinion of all A/C guys off of this. Some of us out there actually know what is going on.
Thank you for the question, I hope I was of some assistance. If I can do anything further during this process, or in the future, please do not hesitate to ask. If you found this response to be of some assistance, please remember to rate this answer. Thanks again and good luck in everything.
