Goodman Heat Pump Error Code b4

The B4 fault code on a Goodman heat pump indicates a blower motor current trip or lost rotor condition. This means the control board detected that the indoor blower motor drew excessive current or failed to spin properly. The system shuts down to prevent damage to the motor windings or other electrical components. The fault must be diagnosed and resolved before the unit will return to normal operation.

No, you should not attempt to continue running the system with a B4 fault active. The code indicates the blower motor is either drawing dangerous levels of current or is not rotating, which means conditioned air is not being circulated. Running the heat pump without proper airflow can cause the heat exchanger or refrigerant coil to reach extreme temperatures, leading to additional component failures or creating a safety hazard.

Repair costs vary depending on what component has failed. Replacing a run capacitor is typically the least expensive repair, often ranging from $75 to $200 including parts and labor. Replacing a blower motor or ECM control module is more involved, with costs generally ranging from $300 to $800 or more depending on the specific motor type and local labor rates. A service call for diagnosis alone typically runs $75 to $150 before any parts costs are factored in.

Some causes of the B4 code are accessible to a knowledgeable DIYer, such as replacing a clogged air filter, clearing debris from the blower wheel, or replacing a failed run capacitor. However, diagnosing and replacing an ECM motor module or a failed blower motor requires electrical testing skills and familiarity with HVAC components. If you are not comfortable working with electrical components inside an air handler, a qualified HVAC technician should perform the diagnosis.

Resetting the system by cycling power may temporarily clear the fault display, but the B4 code will return if the underlying cause has not been corrected. A reset does not fix a seized motor, a failed capacitor, or a faulty motor module. Repeated resets without addressing the root cause can accelerate wear or cause additional damage to the motor and control board.