Heating
Circulation Pump
In short
Circulation Pump: Heating system circulation pump - 3-core (L/N/E). It has 3 terminals: L (Live), N (Neutral), E (Earth).
If this is your home: this page is written for heating engineers. Mains wiring and gas appliances are not DIY jobs; call a Gas Safe registered engineer. If you smell gas, leave the building and call the National Gas Emergency Service on 0800 111 999.
Terminals
| Terminal | What it is | On an S-Plan | On a Y-Plan |
|---|---|---|---|
| L | Live | Boiler PL (pump live) | Boiler PL (pump live) |
| N | Neutral | Wiring centre terminal 2 (neutral) | Wiring centre terminal 2 (neutral) |
| E | Earth | Wiring centre terminal 3 (earth) | Wiring centre terminal 3 (earth) |
How it fails
- Circulating pump seized
The pump has 230 V across L-N but does not run: seized. The boiler overheats and locks out.
Where it connects
Lessons that use it
- The Pump
Component Library
- Pump and System Test
S-Plan Wiring
- Boiler and Pump Connections
Y-Plan Wiring
- No Power to System
Fault Diagnosis
- Heating Not Working
Fault Diagnosis
- Hot Water Not Working
Fault Diagnosis
- Valve Stuck
Fault Diagnosis
- Intermittent Fault
Fault Diagnosis
Systems it is part of
Also in heating
Your first fault is waiting.
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