Carrier Error Code 73: Contactor shorted (Heat Pump)
Carrier error code 73 on a heat pump means: Contactor shorted. It is also called Carrier diagnostic code 73.
Homeowner? What Carrier code 73 means for you
Call a technician Your heat pump is reporting: Contactor shorted. The heat pump has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Check both breakers and the outdoor disconnect box beside the outdoor unit; all should be ON.
- Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
- In winter, keep snow and ice off and away from the outdoor unit. A short defrost cycle with steam is normal.
- Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does Carrier error code 73 mean?
Amber STATUS light flashes 73: compressor voltage is present when there is no call for the compressor.
Applies to: Carrier 25HNB6/25HNB9 two-stage HP; single-stage communicating HP
Common causes of Carrier code 73
- Contactor contacts welded or stuck closed
- Miswired control box
Carrier models that use code 73
25HNB62425HNB63625HNB64825HNB66025HNB92425HNB93625HNB94825HNB960
Other Carrier Heat Pump codes
All Carrier Heat Pump error codes →
Carrier code 73: homeowner questions
What does Carrier code 73 mean?
Contactor shorted. Amber STATUS light flashes 73: compressor voltage is present when there is no call for the compressor.
Is it safe to keep using my heat pump with code 73?
It depends on the cause. The heat pump has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.
Can I reset Carrier code 73 myself?
You can try one reset (power off for 30 seconds, then on). If Carrier code 73 comes back, the cause is still there and a licensed technician should check it.
Who can fix Carrier code 73 near me?
Aurora Star Tech Inc. repairs Carrier heat pumps in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: AC Running But Not Cooling: What to Check · Heat Pump Not Heating or Blowing Cold Air
Troubleshooting guides
- Amber STATUS or green COMM light not on Carrier · Heat Pump
- Delay before the compressor restarts Carrier · Heat Pump
- Heat pump will not defrost - HK32EA defrost board Carrier · Heat Pump
- Noisy compressor or loud defrost shift - Carrier split systems Carrier · Heat Pump
- Outdoor ECM fan not running - Carrier 25HNB9/24ANB1 Carrier · Heat Pump
- Outdoor unit unresponsive after several faults Carrier · Heat Pump
- Outdoor unit will not run - HK32EA defrost board heat pumps Carrier · Heat Pump
Source: Carrier Residential AC & HP Application Guideline and Service Manual 24-25-9SM (text export), Table 14 Status Codes / Table 18 Troubleshooting. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.