HGT1 on a Kensa heat pump: Ground return temperature T5 above the Cooling Mode upper limit
Short answer
On a Kensa heat pump, HGT1 means: Ground return temperature T5 above the Cooling Mode upper limit. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 4 sources
What it means
The manual says: Ground return temperature T5 above the Cooling Mode upper limit.
Part involved: T5 / ground circuit (cooling).
When it shows: Error level per manual: Fault or Warning.
Likely causes:
- Inadequate ground flow, ground pump failure, incorrect cooling upper-limit setting.
Is it safe?
| 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 - clears when condition clears (per manual action text).
Manual reset: unknown.
What you can check
- Note the code shown on the controller/LED; check the heat pump isolator and consumer-unit breaker are on; check thermostat/timer settings.
What the engineer will check
- Follow Kensa fault table actions: Inadequate ground flow, ground pump failure, incorrect cooling upper-limit setting.
Who to ask for: GSHP / ground-loop installer.
Certification: MCS-certified GSHP installer recommended; Kensa-trained.
What you might notice
Sources
- Kensa Evo Heat Pump Installation manual ↗ · V32 · page 51 · Reviewed 23 September 2026
- Q80 Series Heat Pump Operational Manual ↗ · Version 2 · page 24 · Reviewed 23 September 2026
- Shoebox Heat Pump Operational Manual (User Manual) ↗ · Version 8 · page 27 · Reviewed 23 September 2026
- Kensa Shoebox NX heat pump Installation manual ↗ · V12 · page 42 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026