Santon PREMIER PLUS, Installation And Servicing Instructions, Page: 21 / 28

Fault Possible Cause Remedy
No hot water flow
Mains water supply off Check and open stop cock
Strainer blocked Turn off water supply. Remove strainer and
clean
Cold water combination valve incorrectly
fitted
Check and refit as required
Water from hot tap
is cold
Direct immersion heater not switched on Check and switch on
Direct immersion heater thermal cut-out
has operated
Check, reset by pushing button on thermostat
Indirect programmer set to central heat-
ing only
Check, set to domestic hot water programme
Indirect boiler not working Check boiler operation. If fault is suspected
consult boiler manufacturer’s instructions
Indirect thermal cut-out has operated Check, reset by pushing button on thermostat
Check operation of indirect thermostat
Indirect motorised valve not connected
correctly
Check wiring and/or plumbing connections to
motorised valve
Water discharges
from expansion
valve
INTERMITTENTLY
Expansion vessel charge pressure has
reduced below 3.5bar, or set to high
See Maintenance section for re-charging of
expansion vessel procedure
CONTINUALLY
cold water combination valve pressure
reducer not working correctly.
Expansion valve seat damaged
Check pressure from cold water combination
valve. If greater than 3.5bar replace pressure
reducing valve
Remove expansion valve cartridge, check
condition of seat. If necessary fit new expansion
valve
Water discharges
from T&P relief
valve
Thermal control failure
NOTE: water will be very hot
Switch off power to immersion heater(s) and
shut down boiler.
DO NOT turn off water supply. When discharge
stops check all thermal controls, replace if faulty
Milky water
Oxygenated water Water from a pressurised system releases
oxygen bubbles when flowing. The milkiness will
disappear after a short while
Table 5 - Fault finding chart