Heat pumps · Error codes · Kensa
LVKensa
LV on a Kensa heat pump: Supply voltage below the low-voltage limit
Short answer
On a Kensa heat pump, LV means: Supply voltage below the low-voltage 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: Supply voltage below the low-voltage limit.
Part involved: Mains supply.
When it shows: Error level per manual: Fault.
Likely causes:
- Supplied voltage less than the low-voltage limit.
- Undersized or loose supply cabling, weak supply.
Is it safe?
Switch the heat pump off at its isolator and call an engineer.
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
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. If breakers keep tripping, leave off and call an electrician.
What the engineer will check
- Follow Kensa fault table actions: Supplied voltage less than the low-voltage limit. Measure supply voltage under load; check supply cable sizing and terminations.
Who to ask for: Electrician.
Certification: Qualified electrician (BS 7671).
What you might notice
Sources
- Kensa Evo Heat Pump Installation manual ↗ · V32 · page 52 · Reviewed 23 September 2026
- Q80 Series Heat Pump Operational Manual ↗ · Version 2 · page 25 · Reviewed 23 September 2026
- Shoebox Heat Pump Operational Manual (User Manual) ↗ · Version 8 · page 28 · 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