ICP Error Code Green POWER LED: Comfort Alert green POWER LED – module powered (Heat Pump)

Updated October 15, 2026 · by Aurora Star Tech Inc.

ICP error code Green POWER LED on a heat pump means: Comfort Alert green POWER LED - module powered. It is also called ICP diagnostic code Green POWER LED.

Low severityHeat PumpICP N4H3 Heat Pump

Homeowner? What ICP code Green POWER LED means for you

Usually minor Your heat pump is reporting: Comfort Alert green POWER LED - module powered. This code is usually informational or minor. The safe checks below often clear it; call us if it keeps showing up.

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) 657-2977 Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does ICP error code Green POWER LED mean?

On heat pumps fitted with the Comfort Alert diagnostic module, the green POWER LED lit means the module has 24 VAC power. Normal. The red TRIP and yellow ALERT LEDs only come on for a problem.

Applies to: ICP N4H3 heat pumps with Comfort Alert

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

ICP models that use code Green POWER LED

N4H3

Other ICP Heat Pump codes

Code	Meaning
5	Open circuit
6	Open start circuit
7	Open run circuit
8	Welded contactor
9	Low voltage
Defrost SPEEDUP test	Defrost board SPEEDUP pin test
Red TRIP LED	Comfort Alert TRIP - Y1 call but compressor not running
TRIP + ALERT flashing together	Control voltage too low

All ICP Heat Pump error codes →

ICP code Green POWER LED: homeowner questions

What does ICP code Green POWER LED mean?

Comfort Alert green POWER LED - module powered. On heat pumps fitted with the Comfort Alert diagnostic module, the green POWER LED lit means the module has 24 VAC power. Normal. The red TRIP and yellow ALERT LEDs only come on for a problem.

Is it safe to keep using my heat pump with code Green POWER LED?

Usually yes. Code Green POWER LED is normally minor, but if it keeps coming back have it checked.

Can I reset ICP code Green POWER LED myself?

You can try one reset (power off for 30 seconds, then on). If ICP code Green POWER LED comes back, the cause is still there and a licensed technician should check it.

Who can fix ICP code Green POWER LED near me?

Aurora Star Tech Inc. repairs ICP 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

Comfort Alert module basics ICP · Heat Pump
Defrost not working - test the defrost board ICP · Heat Pump
Force a defrost with the SPEEDUP pins ICP · Heat Pump

Source: ICP N4H3 Installation Instructions 428 01 5103 02, Figure 18 Comfort Alert status LEDs, p.19. 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.