Not much can ruin an HVAC system’s cooling ability like a dirty evaporator. Even if the rest of the system is in perfect operating condition, a dirty evaporator can cause high cooling bills and a hot house. Signs of a dirty evaporator include freezing up and low air flow at vents. The most common reasons for this is either a filter has been removed allowing dust in the air to collect on the evaporator or the filter hasn’t been changed in a very long time and it has partially collapsed or been dislodged. It’s imperative to always keep filters in use and a dirty filter is better than none at all. Evaporator coils can be difficult to clean (particularly upflow) and should be done by an hvac technician.
