Goodman Error Code Yellow 1 flash: Low side fault / low pressure trip / low pressure lockout (older ComfortNet board) (Heat Pump)
Goodman error code Yellow 1 flash on a heat pump means: Low side fault / low pressure trip / low pressure lockout (older ComfortNet board). It is also called Goodman diagnostic code Yellow 1 flash.
Homeowner? What Goodman code Yellow 1 flash means for you
Call a technician Your heat pump is reporting: Low side fault / low pressure trip / low pressure lockout (older ComfortNet board). 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 Goodman error code Yellow 1 flash mean?
Yellow LED 1 flash. Green OFF + red OFF = low side fault (4 protector trips, average run over 3 h). Green ON + red OFF = low pressure switch opened. Green ON + red ON = low pressure lockout. Same meaning as 7-segment codes 01 / L1 on newer boards.
Applies to: Earlier ComfortNet condensers/heat pumps with the PCBHR101-103 or PBBGR101-102 outdoor control (green, yellow and red status LEDs) - ASXC/DSXC/ASZC/DSZC revisions before the PCBHR104 change
Common causes of Goodman code Yellow 1 flash
- Low refrigerant charge
- Restricted liquid line (drier, kinked line)
- Indoor blower motor failed or not running
A technician checks these and 1 other possible causes on site before replacing any part.
Goodman models that use code Yellow 1 flash
Show all 24 models
ASZC160241ASZC160361ASZC160421ASZC160481ASZC160601ASZC180241ASZC180361ASZC180481ASZC180601DSZC160241DSZC160361DSZC160481DSZC160601DSZC180361DSZC180481DSZC180601GSZC160241GSZC160361GSZC160481GSZC160601GSZC180241GSZC180361GSZC180481GSZC180601
Other Goodman Heat Pump codes
All Goodman Heat Pump error codes →
Goodman code Yellow 1 flash: homeowner questions
What does Goodman code Yellow 1 flash mean?
Low side fault / low pressure trip / low pressure lockout (older ComfortNet board). Yellow LED 1 flash. Green OFF + red OFF = low side fault (4 protector trips, average run over 3 h). Green ON + red OFF = low pressure switch opened. Green ON + red ON = low pressure lockout. Same meaning as 7-segment codes 01 / L1 on…
Is it safe to keep using my heat pump with code Yellow 1 flash?
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 Goodman code Yellow 1 flash myself?
You can try one reset (power off for 30 seconds, then on). If Goodman code Yellow 1 flash comes back, the cause is still there and a licensed technician should check it.
Who can fix Goodman code Yellow 1 flash near me?
Aurora Star Tech Inc. repairs Goodman 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
- No heat - R-32 GLZS/ALZS heat pump Goodman · Heat Pump
- Outdoor coil iced / no defrost - R-32 GLZS/ALZS heat pump Goodman · Heat Pump
- Reversing valve not shifting - ComfortNet heat pumps Goodman · Heat Pump
Source: Goodman ComfortNet ASXC/GSXC/DSXC, ASZC/GSZC/DSZC, AVPTC/MBVC service manual, diagnostic/status LED table (PCBHR101-103, PBBGR101-102) p.65-69. 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.