E4 on a Gree heat pump: High discharge protection
Short answer
On a Gree heat pump, E4 means: High discharge protection. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 23 September 2026 · 6 sources
What it means
On the Versati II (R410A)
The manual says: High discharge protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
Likely causes:
- The resistance of temperature sensor is not correct.
- The electric expansion valve is blocked.
- The system has leaked.
- Mainboard of outdoor unit is damaged.
On the Versati III Monobloc (R32)
The manual says: High discharge protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
On the Versati III Split / All-in-one (R32)
The manual says: High discharge protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
On the Versati IV Monobloc (R32)
The manual says: Comp Discharge temp protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
Likely causes:
- The resistance of temperature sensor is not correct.
- The electronic expansion valve is blocked.
- The system has leaked.
- Mainboard of outdoor unit is damaged.
On the Versati IV Split / All-in-one (R32)
The manual says: High discharge protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
Likely causes:
- Discharge temperature sensor faulty.
- Electronic expansion valve blocked.
- Refrigerant leak / insufficient charge.
- Mainboard AP2 faulty.
On the Versati V R290 Monobloc
The manual says: High discharge protection.
Part involved: compressor, pressure switches, expansion valve, refrigerant charge.
Is it safe?
On the Versati II (R410A)
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Safety lockout |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: yes.
Manual reset: If it occurs for 3 times during one hour, it is cleared by de-energization. If it occurs for less than 3 times, it will be automatically cleared.
On the Versati III Monobloc (R32)
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
On the Versati III Split / All-in-one (R32)
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
On the Versati IV Monobloc (R32)
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: yes.
On the Versati IV Split / All-in-one (R32)
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
On the Versati V R290 Monobloc
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
What you can check
- Note the code shown on the controller and the unit model numbers (on the rating plate label) before contacting your installer.
- Check the heat pump's breaker/isolator at the consumer unit is on; do not open any casing.
- Check the outdoor unit is not blocked by leaves, debris, snow or ice and that nothing is stored against the grilles.
What the engineer will check
- Follow the Gree troubleshooting flowchart for this code in the service manual.
- Check refrigerant pressures and charge (F-gas / flammable refrigerant competent person only).
- Check expansion valve, pressure switches/sensors and discharge temperature.
- Check outdoor coil airflow and blockages.
Who to ask for: Heat pump engineer.
Certification: Heat pump installer competence; F-gas / flammable-refrigerant (R290/R32) handling competence for any refrigerant-circuit work.
What you might notice
Sources
- Air to Water Heat Pump Service Manual Versati II (T1/R410A/50Hz, GC201308-) ↗ · GC201308 · page p.60 (printed; PDF p.63) · Reviewed 23 September 2026
- VERSATI III Air To Water Heat Pump (Monobloc) Service Manual ↗ · page p.121 (printed; PDF p.121) · Reviewed 23 September 2026
- Service Manual for VERSATI R32 SPLIT (VERSATI III Split Type Air To Water Heat Pump) ↗ · page p.108 (printed; PDF p.112) · Reviewed 23 September 2026
- Air-to-water Heat Pump Owner's Manual (Versati IV Monobloc, SG version) ↗ · page p.54 (printed; PDF p.58) · Reviewed 23 September 2026
- VERSATI IV Split Type Air To Water Heat Pump Service Manual ↗ · page p.66 (printed; PDF p.76) · Reviewed 23 September 2026
- VERSATI V Monobloc Type Air-to-water Heat Pump Service Manual (R290) ↗ · page p.30 (printed; PDF p.33) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026