Why Is My AC Running But Not Cooling Properly?

Your AC may run but not cool due to a clogged filter, dirty outdoor coil, low refrigerant, a bad capacitor, or the thermostat set to “fan.” Closed or blocked vents and frozen coils also reduce cooling. Ultimate Heating & Air offers 24/7 diagnostics and repairs in Boise, Nampa, and Caldwell.

Quick checks:

• Set thermostat to Cool and Auto.
• Replace or clean the filter.
• Clear debris around the outdoor unit.
• Open all supply and return vents.
• If coils are iced, turn system off.

Updated: 2026-01-02

Need help in Caldwell, ID? Call (208) 738-4822 or book online.