C
44
Moderate
Carrier · Central Air Conditioners & Furnaces
Blower RPM Below Set Speed
Quick Answer
Error code 44 on your Carrier Central Air Conditioners & Furnaces means: Blower RPM Below Set Speed. This is usually fixable — see the step-by-step guide below.
Likely Causes
  1. Dirty blower wheel causing imbalance and reduced airflow
  2. Failing ECM blower motor losing speed control
  3. Restricted ductwork causing excessive static pressure on blower
  4. Incorrect blower speed settings on control board dip switches
How to Fix It
1
Remove and clean the blower wheel thoroughly with a coil cleaner or degreaser
2
Verify blower speed dip switch settings match the installation requirements
3
Measure static pressure in the duct system and compare to specifications
4
Check ECM motor for fault codes using the motor's built-in LED diagnostics
5
If motor cannot maintain speed after cleaning, replacement is likely needed
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
ECM blower motor
Blower wheel
Coil cleaning solution
Related Error Codes
Video Guides
Loading video guides…
Search more on YouTube →