Extract from 'Central Heating - Fault Finding &
Repair'
No Central
Heating. No Hot Water
Reason
Pump failure - no electrical supply.
Pump failure - burnt out motor windings due to pump
being covered with insulation, linen etc.
Pump failure - rotor seized due to rust/sludge sediment
inhibiting pump speed.
Pump failure - worn out bearing(s) due to wear and
tear and/or incorrect installation.
Pump failure - burnt out motor windings due to seized
rotor.
No Central Heating. Hot Water O.K.
Reason
Room thermostat faulty so no signal to pump.
2 port zone/3 port motorised valve faulty.
No Hot Water. Central Heating O.K.
Reason
2 port zone/3 port motorised valve faulty.
Cylinder thermostat faulty so no signal to pump.
Insufficient Heat to Radiators.
Reason
Speed setting too slow.
Pump running slow due to rust/sludge sediment
inhibiting pump speed.
Frequent Boiler Shut Down
Reason
Pump on low speed causing the boiler thermostat
to activate.
Pump running slow due to rust/sludge sediment
causing the boiler thermostat to activate.
Noise
Reason
Pump running too fast
Air in system/pump
Air in system/pump due to ‘pumping over’
Dry running of top bearing due to incorrect
pump installation
Impeller out of balance due to wear and tear
Cavitation in pump.
Water ‘Pumping Over’ into
Feed and Expansion Cistern
Reason
Pump running too fast.
Incorrect system design/pump location.
Reverse Circulation
Reason
Apparent flow in circuits that have motorised
valves
that are closed.
Extract from 'Central Heating - Fault Finding &
Repair'
|
Repair
Check electrical connections at pump, wiring centre,
boiler, etc.
Replace pump and allow air to freely circulate around
pump.
Repair rotor movement or replace pump.
Replace pump and/or correct installation fault.
Replace pump.
Repair
Repair/check room thermostat.
Check motorised valve(s).
Repair
Check motorised valve(s).
Check cylinder thermostat.
Repair
Increase speed setting.
Flush and protect central heating system and
overhaul pump.
Repair
Increase speed setting.
Flush and protect central heating system and
overhaul pump.
Repair
Speed setting too high.
Vent system/pump.
Re-work system pipe work/change pump location.
Adjust angle of pump installation.
Replace pump.
Increase the hight of the F & E cistern or
pressurise the system.
Repair
Speed setting too high.
Re-work system pipe work/change pump location.
Repair
Breaking 3 ‘T’s rule. |
