E8 on an Alpha Heating Innovation Alpha Hydro 5/8/12/16 R32 monobloc: Maximum N° of resets: Number of allowed resets already performed; resets allowed up to 5 times consecutively, then inhibited for at least one hour (one attempt regained per hour; power-cycling restores the 5 attempts)
Short answer
On an Alpha Heating Innovation heat pump, E8 means: Maximum N° of resets: Number of allowed resets already performed; resets allowed up to 5 times consecutively, then inhibited for at least one hour (one attempt regained per hour; power-cycling restores the 5 attempts). The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Maximum N° of resets: Number of allowed resets already performed; resets allowed up to 5 times consecutively, then inhibited for at least one hour (one attempt regained per hour; power-cycling restores the 5 attempts).
Part involved: PCB.
Likely causes:
- Number of allowed resets already performed; resets allowed up to 5 times consecutively, then inhibited for at least one hour (one attempt regained per hour; power-cycling restores the 5 attempts).
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
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.
- Switch the appliance off and on again (manual says this re-acquires the 5 reset attempts).
What the engineer will check
- Investigate the underlying fault that caused repeated resets.
Who to ask for: heat pump engineer.
Sources
- Alpha Pre-Plumb 200 - Pre-plumbed cylinder with Hydro heat pump - Installation and Servicing Instructions (06-23) ↗ · Pre-Plumb 200 instructions 06-23 · page 36 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026