Why is our air conditioning compressor so noisy?

We have a very hot summer this year and have installed the air conditioner 2 month ago. It's a Goodman 10 SEER air conditioner. My problem is that this air-conditioner produces a lot of noise. Two of our neighbors have the same air conditioner installed by the same guys and they are much quieter. The technician looked at it yesterday and admitted that this one is noisier, said that the noise is probably is coming from the compressor and it's normal for it to sound this loud, as all the compressors are different. The noise I can describe as a rattling noise. It's not a fan, as I can hear two of them and the fan produces an even low sound of a blown air. It usually works as follows: at the start of the cycle there is a click and this rattling noise can be heard for a second or two and disappears. Then it gradually increases its level to a full scale in about 20-30 seconds and stays that way until the end of the cycle. I don't know if it's related, but during the installation they dropped the outside end of the thicker copper pipe on the soil and tried to clean it up by shaking and blowing. Potentially, what harm can this do to the air-conditioner? In one of your Ask an Expert questions it says that some compressors are noisy when new and will break in over time. Is two month time enough for it to break in? This noise is bothering me. And I'm afraid it's bothering my neighbors too. What can be done to lower the noise? They suggested for us to buy and install an insulating blanket. The unit is still under 1 year warranty. How can persuade them to fix it?

Erin S. - Editor expert

From your description, I doubt the dirt in the tubing has anything to do with it. It sounds like you have a noisier than average compressor which has not gotten quieter after a reasonable break-in period. An insulating blanket may help with the noise but it lessens the heat dissipation from the compressor, which is arguably harder on the compressor, which could reduce its life expectancy. First of all, I can't imagine why they would want you to pay for the insulating blanket, to solve a problem which is not of your own making. Secondly, I am not sure that it is a good solution for you in the long run. The technician has admitted that you have at noisy compressor. On a two year old unit, this might be a difficult argument to make, but on a two-month old unit, I would think a replacement compressor would be the best solution.