Heat pumps · Error codes · Sime
E8Sime · SHP M Pro
E8 on a Sime SHP M Pro: Water flow malfunction
Short answer
On a Sime heat pump, E8 means: Water flow malfunction. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Water flow malfunction.
Part involved: flow switch / circulation pump.
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: unknown.
What you can check
- Note the code shown on the controller and the model number on the unit's rating label before contacting your installer.
- Check that the heat pump's isolator and consumer-unit breaker are on; do not open any casing.
- Check the heating system pressure gauge reads within the range your installer set (typically 1-2 bar) and that the filling loop is closed.
What the engineer will check
- Check the circulation pump runs and the strainer/filter is clean.
- Vent air from the system.
- Check the flow switch/flowmeter and its wiring.
- Check isolation valves are open and minimum flow/volume is met.
Who to ask for: Heat pump engineer.
Certification: Heat pump installer competence; F-gas and flammable-refrigerant (R32/R290) handling competence for any refrigerant-circuit work.
What you might notice
Sources
- Sime SHP M PRO Installation manual 6332386 R3 (IT/EN/ES/EL) ↗ · R3 · page printed p.57 (PDF p.128) · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026