Heat pumps · Error codes · Dimplex
S12Dimplex · WPM heat pump manager platform (error-code grouping)
S12 on a Dimplex WPM heat pump manager platform: Switch cycle block: required by utility companies, can last up to 20 minutes (max 3 compressor starts per hour)
Short answer
On a Dimplex heat pump, S12 means: Switch cycle block: required by utility companies, can last up to 20 minutes (max 3 compressor starts per hour). The heat pump keeps running with some functions stopped.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Switch cycle block: required by utility companies, can last up to 20 minutes (max 3 compressor starts per hour).
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Information only |
| Engineer needed? | No |
The heat pump keeps running with some functions stopped.
Resetting itself: Automatic.
What you can check
- Wait up to 20 minutes.
What the engineer will check
The manual does not list the engineer’s checks for this code.
What you might notice
Sources
- Dimplex WPM Touch heat pump manager - Operating instructions for users and specialists (Order no. 452117.66.02-EN, WPM3.13 / Display 1.15) ↗ · 452117.66.02-EN FD 0302 · page 56 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026