Grundfos STP 2 fault 7

What it means

Pump running noisily on positive pressure pumps.

Likely causes

1. Pompanın montaj yüzeyinde titreşim var (Vibration on pump mounting surface)
2. Hot-water supply taken directly from top of hot-water cylinder
3. Entrapped air causing airlocks in supply pipe
4. Air not thoroughly purged from system
5. Undersized pipework
6. Pipes routed under floor causing air traps
7. Other outlets fitted in inlet pipes
8. Shared (non-dedicated) hot/cold supplies
9. Blanked-off pipes
10. Restrictions in flexible hoses
11. Unsecured pipework
12. Leak in system
13. Drip in system
14. Air trapped in pump
15. Leak causing loss of tank air pressure
16. Debris ingress into pump causing blockage or damage if strainer omitted

Where to start

1. Check hot-water supply connection point on cylinder
2. Inspect for airlocks in supply pipe
3. Purge all air from system