When I first moved into the lake condo I renting right now, there was this irritating whistle category sound coming out of the air vents every single time the central heating and a/c equipment would kick on.
For the first month I put up with it thinking this may be normal and will work itself out.
Well, that did not happen. So, looking into this further I found that the solution was simple. And I was cheerful I did not waste money on having to call a heating and a/c supplier. Because it turned out that the air vents were not fully opened! And in turn, the air flow would be blocking everytime the central heating and a/c equipment came on. So I got up on a ladder, went around the condo and opened up every single air vent one by one to the fullest. Then after this, when the central heating and a/c would come on it no longer made the whistle noise that had been going on since the day i moved in. Had I called the local heating and a/c supplier, this would have cost a few hundred dollars just to go around the condo to open up a few lousy air vents. I think you are thinking shouldn’t the property owner or management pay for heat and a/c service? Ordinarily yes, however I have a special low rental rate with the clause that I take care of any complications that may arise around the house. So that is what I am doing now.