6.3 Fault Finding
Symptom
Possible cause
Possible remedy
Little / no
hot water flow
Mains water supply isolated
Open stopcock.
Strainer blocked
Turn water supply off, remove strainer and clean.
Pressure reducing valve fitted the wrong
way
Refit with arrow pointing in direction of flow
Water from
hot taps is cold
Boiler programmer or immersion timer not
calling for hot water
Set programmer / timer to call.
Cylinder thermostat high limit tripped or
immersion thermostat high limit tripped
Check and reset.
Heat source malfunction
(e.g. boiler / immersion heater / etc)
Check heat source
– if faulty, refer to heat source
manufacturer’s instructions.
Motorised valve malfunction
(where fitted, n/a to Direct models)
Manually activate motorised valve.
If cylinder begins to heat, replace valve.
Pump malfunction
(n/a to Direct models)
Check wiring and/or plumbing connections to pump.
Intermittent
water discharge
from tundish
Expansion vessel has lost its pre-charge
Turn off water supply, open hot tap, check bladder
pre-charge and recharge to 3 bar.
Inlet group balanced cold / cylinder
connections reversed
Check and reconnect.
Continuous
water discharge
from tundish
Pressure reducing valve not working
Check pressure from pressure reducing valve
– if
greater than 3 bar, replace cartridge.
Expansion relief valve not seating correctly
Manually operate the valve to clear any debris from
the seat.
Temperature & pressure relief valve not
seating correctly
Manually operate the valve to clear any debris from
the seat.
System control / safety feature failure
IMMEDIATELY switch off all power supplies.
Contact your installer.
