Heat pumps · Error codes · Lämpöässä
temp-not-risenLämpöässä · Vsi / Vmi (ÄssäControl) GSHP with 430 l tank
temp-not-risen on a Lämpöässä Vsi / Vmi GSHP with 430 l tank: Storage tank temperature not achieved in set time; electric heating enabled
Short answer
On a Lämpöässä heat pump, temp-not-risen means: Storage tank temperature not achieved in set time; electric heating enabled. The heat pump keeps running. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Storage tank temperature not achieved in set time; electric heating enabled.
Likely causes:
- Storage tank temperature not achieved in set time; electric heating enabled.
Is it safe?
| Does the heat pump stop? | No |
|---|---|
| Severity | Information only |
| Engineer needed? | Yes |
The heat pump keeps running.
What you can check
- Note the code and any text shown on the display/controller.
- Check the heat pump isolator and consumer-unit breaker are on.
What the engineer will check
- Check heat demand and compressor operation; no action needed during commissioning pre-heating (manual).
Who to ask for: heat pump engineer.
Sources
- LÄMPÖÄSSÄ Vmi 6-17 Ground Source Heat Pump - Instructions for use, installation and maintenance (7/2017) ↗ · 7/2017 · page 22 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026