It is perfectly normal for your AC System to make certain sounds such as the continuous humming noise while it’s running.
However, when you begin to hear strange/unfamiliar noises emanating from your outdoor AC unit, this could be an indication that something is really wrong. In such cases, it would be wise to contact a licensed and well-qualified HVAC contractor immediately.
So, let’s begin to with our list of AC noises that should concern you.
Over time, and with greater and greater usage, your AC system will tend to exhibit more noises. When an AC system starts squealing or screeching, this can be a sign of a part such as a belt or ball bearing is worn out and in need of replacement or has become misaligned. When this happens, it’s best to call a professional HVAC repair company to properly diagnose and fix your AC unit’s issue.
Metal against Metal
If ever you hear the sound of metal scraping or otherwise rubbing against metal in your AC system, it’s recommended that you immediately shut off your AC.
There are any number of reasons why this could be happening, but it’s likely to be a serious problem that needs to be addressed quickly to avoid any hazard and/or an even more costly repair bill.
While it is common for older furnaces to start and stop with a thumping sound, it should not the case during normal operation.
So, if you do begin hearing thumping or knocking sounds while your furnace is running, this could mean that something may be seriously wrong. We recommend that you call a qualified HVAC professional to address this potential issue. If there is a faulty or broken part, an experienced AC tech can fix it.