AC (indoor) ice forming on unit?

A blocked air filter starves the evaporator coil of warm air, causing its surface temperature to drop below freezing and ice to form.

Likely causes · most likely first

Air Filter

Easy DIY Part: $10–$25
Heat Exchanger (Evaporator)

Moderate DIY Part: $150–$350

A fouled heat exchanger reduces airflow through the coil fins, allowing moisture to freeze on the coil surface.
Fan Motor

Hard DIY Part: $40–$90

A slow or failing fan motor reduces air volume over the coil, causing coil temperatures to fall below the freezing point.
Main PCB

Moderate DIY Part: $80–$200

A faulty PCB may disable the defrost cycle or run the compressor continuously without calling for defrost, leading to ice accumulation.

See the faulty part in 3D.

Tap a highlighted part to see exactly why it fails, how to verify it's the problem, and how to replace it.