After AC & Furnace Company came to install additional coolant in our AC unit, our unit make a very loud hum. I waited a few weeks to see if it would go away but it did not. When calling back to have the representative speak to the issue, his first response was to say "there's nothing to be done", then "it's the unit's fault" and "that's just bad luck".
I called 4 days outside the 30 day warranty, having given his labour the benefit of the doubt and so he would not come to investigate the issue further at all. By the time we got to the warranty part of the conversation, I was already quite exasperated with his approach.
The phone call was an unpleasant service experience, and I do not recommend this company.