Carrier DF status display

What it means

DF means the heat pump is melting frost from the outdoor unit during heating. Carrier's manual says DF in defrost mode is not an error code.

Urgency

Likely causes

Homeowner fix

Let the defrost cycle finish. Steam, water, and a short pause in warm indoor airflow can be normal during defrost.

When to call a pro

Call for service only if DF never clears, the outdoor unit is encased in ice, or heating does not resume after the cycle.

Repair vs replace

This is a normal operating or service status, not a repair-or-replace decision.

• Carrier Comfort 22 9,000 BTU R-454B 115V (45MHHAQ09XC1 / 37MHRAQ09AA1)

  Comfort 22

• Carrier Comfort 22 9,000 BTU R-454B 208/230V (45MHHAQ09XC3 / 37MHRAQ09AA3)

  Comfort 22

• Carrier Comfort 22 12,000 BTU R-454B 115V (45MHHAQ12XC1 / 37MHRAQ12AA1)

  Comfort 22

• Carrier Comfort 22 12,000 BTU R-454B 208/230V (45MHHAQ12XC3 / 37MHRAQ12AA3)

  Comfort 22

For your technician

N/A. Carrier notes DF is not an error code. Page context: Carrier maps this display to the Comfort 22 line; source: Carrier 45MHHAQ High Wall Heat Pump Owner's Manual, Table 4 Error Codes; display convention: match the letter D and letter F marker exactly before comparing neighboring codes.

Which systems show it

Comfort 22

Related troubleshooting

Use the symptom guide alongside the exact display code if the unit is flashing, cycling, or showing comfort symptoms.

Related codes

Source

Next step