An HVAC system with a loud knocking or thumping sound definitely warrants your attention. Usually, it is a result of a missing screw or loose belt, both of which are easy to fix. It,however, might also be the sound of a serious malfunction, so call in a technician to check it out.
Other noises such as a loud explosion and sudden rattle may require calling in an expert on heating and air conditioning repair in Rancho Cucamonga. Bringing in an expert such as Day Aire can help find problems in your HVAC systems and have them repaired promptly.