Modern heat pumps display error or fault codes on the indoor unit or controller display when a problem is detected — these codes point directly to the system fault and make diagnosis faster and more accurate.
HeatLand Heating & Cooling installs and services heat pumps across Greater Vancouver.
Call (604) 330-3812 Get a Free QuoteWhat This Means
Error codes are generated by the heat pump control board when sensors or safety controls detect an out-of-range condition. The code identifies which sensor or control triggered and gives the technician a starting point for diagnosis.
Common Causes
- E1/F1 codes — typically communication errors between indoor and outdoor units
- E3/H6 — outdoor fan motor fault
- E5/P1 — high pressure protection tripped
- E6 — communication fault or outdoor unit fault
- F2 — indoor temperature sensor fault
- H3 — compressor overload protection
- C5 or similar — refrigerant circulation fault
What Homeowners Can Check Safely
- Write down the exact code displayed before resetting the system — codes are important diagnostic information
- Try one reset: turn the system off at the thermostat, wait 5 minutes, restart. If the code returns immediately, the fault is active and persistent
When to Call a Licensed Technician
Heat pumps contain refrigerant under pressure, electrical components at line voltage, and control systems that require specialized diagnostic tools. Do not open refrigerant circuits, bypass safety switches, or attempt to recharge refrigerant without proper certification.
- Code-specific diagnosis using the equipment service manual
- Sensor resistance testing for temperature sensor codes
- Pressure testing for high-pressure and low-pressure fault codes
- Communication wiring inspection for communication fault codes
- Compressor testing for compressor-related codes
Frequently Asked Questions
Why does my heat pump keep showing the same error code after I reset it?
A recurring error code means the underlying fault is still present. Resetting clears the code but not the cause. For example, if a high-pressure code keeps returning, the high-side pressure is genuinely elevated and will keep triggering the cutout until the cause is resolved (dirty coil, refrigerant overcharge, etc.).
Where can I find the meaning of my heat pump error code?
Error code definitions are in the service manual for your specific model. The brand and model number are on the data plate of both indoor and outdoor units. Many manufacturers also publish error code lists on their websites. Your HVAC technician will have access to the service manual and diagnostic tools for your brand.
HeatLand services and installs heat pumps throughout Greater Vancouver. Call for expert diagnosis.
Call (604) 330-3812 Book a Heat Pump Check