Reliance hybrid/heat pump water heater shows F1 and runs only in backup electric mode or not at all

Safety first: Turn OFF power at the breaker. Do not attempt to open the sealed refrigeration system yourself.

Steps to check:

• 1. Listen for compressor: When calling for heat pump operation, you should hear the compressor start. If only the fan runs, F1 may indicate compressor failure.
• 2. Inspect wiring: Remove the upper cover and inspect the compressor wiring harness and connectors. Look for burned terminals or loose plugs. Reseat connectors.
• 3. Check for tripped overload: Some compressors have an external overload device. If accessible, verify it is not physically damaged. Overloads that trip repeatedly indicate deeper issues.
• 4. Try electric-only mode: If the unit allows, set it to electric-only mode. If it heats normally in this mode, the issue is isolated to the heat pump section.
• 5. Call a professional: Compressor and refrigerant issues require EPA-certified service. A technician can check pressures, electrical characteristics, and determine if the compressor or sealed system must be replaced.

Warning: Do not puncture or cut refrigerant lines. Refrigerant exposure and improper handling are hazardous and illegal without proper certification.