E7 on a Daikin heat pump: Code shown on the remote controller for the installation error(s): Fan motor junction connectors (X1A-X4A) not reconnected after inverter service (Flex outdoor installation manual, test-operation table)
Short answer
On a Daikin heat pump, E7 means: Code shown on the remote controller for the installation error(s): Fan motor junction connectors (X1A-X4A) not reconnected after inverter service (Flex outdoor installation manual, test-operation table). The manual does not say whether the heat pump stops. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 23 September 2026 · 3 sources
What it means
On the Altherma Flex Type
The manual says: Code shown on the remote controller for the installation error(s): Fan motor junction connectors (X1A-X4A) not reconnected after inverter service (Flex outdoor installation manual, test-operation table).
Part involved: outdoor fan motor.
When it shows: Detected during test operation / normal operation after installation errors listed.
Likely causes:
- Fan motor junction connectors (X1A-X4A) not reconnected after inverter service.
On the Altherma HT (high temperature split)
The manual says: Malfunction of outdoor unit fan motor.
Part involved: outdoor fan motor.
When it shows: When the fan runs with speed less than a spec ified one for 6 seconds or more when the fan motor running conditions are met When malfunction is generated 4 ti mes, the system shuts down.
Likely causes:
- Malfunction of fan motor; The harness connector between fan motor and PC board is left in disconnected, or faulty connector; Fan does not run due to foreign matters tangled; Clearing condition: Operate for 5 minutes (normal); Open phase L1 or open phase N. ESIE09-08C.
On the Altherma LT (low temperature split)
The manual says: DC fan lock.
Part involved: outdoor fan motor.
When it shows: ■ The fan does not start in 30 seconds even when the fan motor is running. ■ The system will be shut down if the error occurs 16 times. ■ Clearing condition: Continuous run for about 5 minutes (normal) | The fan does not start in 30 seconds even when the fan motor is running. The system will be shut down if the error occurs 16 times. Clearing condition: Continuous run for about 5 minutes (normal).
Likely causes:
- Fan motor breakdown; Harness or connector disconnected between fan motor and PCB or in poor contact; Foreign matters stuck in the fan.
Is it safe?
On the Altherma Flex Type
| Does the heat pump stop? | Not stated |
|---|---|
| Engineer needed? | Yes |
The manual does not say whether the heat pump stops.
Resetting itself: unknown.
Manual reset: After correcting the abnormality press BS3 RETURN on the outdoor PCB to reset and repeat the test operation (installer only).
On the Altherma HT (high temperature split)
| Does the heat pump stop? | Not stated |
|---|---|
| Engineer needed? | Yes |
The manual does not say whether the heat pump stops.
Resetting itself: unknown.
On the Altherma LT (low temperature split)
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: Reset via the remote controller (Inspection/Test button) after the cause is fixed; some codes need a manual reset of the remote-controller memory (service manual section 1.4).
What you can check
- Read the full error code shown on the user interface and note it, with the date/time, for your installer.
- Check the heat pump isolator switch(es) and the consumer-unit breaker/RCD for the heat pump are ON. If a breaker or RCD has tripped, do not keep resetting it - leave it and call an engineer.
- Look at the outdoor unit from outside: check the air inlet/outlet and fan grille are not blocked by leaves, debris, snow or heavy ice build-up (do not remove panels or touch the fan).
What the engineer will check
On the Altherma Flex Type
- Installer remedial action per manual: open stop valves; correct phase sequence; check power wiring; check piping/wiring consistency; correct refrigerant charge by recalculation; repeat test operation within -20~35 C.
Who to ask for: Heat pump engineer (Daikin-trained).
Certification: Electrical competence to BS 7671; F-gas if refrigerant circuit affected.
On the Altherma HT (high temperature split)
- Follow the service-manual troubleshooting flow chart for this code: check malfunction of fan motor; check the harness connector between fan motor and PC board is left in disconnected, or faulty connector; check fan does not run due to foreign matters tangled; check clearing condition: Operate for 5 minutes (normal); check open phase L1 or open phase N. ESIE09-08C.
Who to ask for: Heat pump engineer (Daikin-trained).
Certification: Electrical competence to BS 7671; F-gas if refrigerant circuit affected.
On the Altherma LT (low temperature split)
- Follow the service-manual troubleshooting flow chart for this code: check fan motor breakdown; check harness or connector disconnected between fan motor and PCB or in poor contact; check foreign matters stuck in the fan.
Who to ask for: Heat pump engineer (Daikin-trained).
Certification: Electrical competence to BS 7671; F-gas if refrigerant circuit affected.
What you might notice
What owners and engineers report
2 owner and engineer reports mention this.
- No heating on the Altherma LT (low temperature split): 1 report
- Outdoor fan not spinning on the Altherma LT (low temperature split): 1 report
Sources
- Installation manual Daikin Altherma Flex EMRQ8-16AAY1 (4PWEN61262-1B) ↗ · 4PWEN61262-1B · page 32 (printed 29) · Reviewed 23 September 2026
- Service Manual Daikin ALTHERMA HT ERSQ/ERRQ 011-016 AA V1/Y1 + EKHBRD (ESIE09-08C) ↗ · ESIE09-08C · page 172 · Reviewed 23 September 2026
- Service Manual ALTHERMA ERHQ006~008BAV3 / ERLQ006~008BAV3(9) / EKHBH(X)008BA (ESIE10-02) ↗ · ESIE10-02 · page 162 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026