21
FAULT
POSSIBLE CAUSES
REMEDY
1) Mains cold water
Check and open Isolating
supply shut off
and/or stop valve. Check
water, Local Water Authority
NO HOT WATER
2) Line strainer
Turn off mains water supply,
FLOW
blocked
remove line strainer and
clean
3) Cold Water
Check direction of flow
Combination valve
arrows on valve, refit in
fitted incorrectly
correct position if necessary
1) Low mains water
Check pressure, consult
pressure
Local Water Authority if
necessary
REDUCED FLOW
2) Line strainer
Turn off mains water supply,
RATE
partially blocked
remove line strainer and
clean
3) Size of service
Increase to size stated on
pipe too small
page 6
1) Direct immersion
Check immersion heater,
heater is not
switch on if necessary
switched on
2) Direct thermal
Test thermostat operation
cut-out has
and wiring, if faulty,
operated
correct/replace. Reset cut-out
WATER FROM
3) Boiler programmer
Check switch on domestic
HOT TAPS
set to central
hot water if necessary
IS COLD
heating only
(Indirect models)
4) Boiler is not
Check boiler operation, if
functioning
fault suspected consult
(Indirect models)
manufacturer's instructions
5) Indirect thermal
Test thermostat operation
cut-out has
and wiring, if faulty,
operated
correct/replace. Reset
cut-out
6) Motorised valve
Check wiring and operation of
jammed or not
motorised valve correct/
wired correctly
replace as necessary
(Indirect models)
DISCHARGE FROM
1) Pressure above 7
Shut down boiler or immersion
PRESSURE/
bar, failure of
heater. Check pressure
TEMPERATURE
pressure reducing
reducing valve and thermal
RELIEF VALVE
valve. Temperature
controls. Replace if
above 90 C failure
necessary
of thermal control
DISCHARGE FROM
1) Continually.
Check pressure from valve.
EXPANSION
Pressure reducing
Replace if over 3.5 bar
VALVE
valve faulty
2) When heater is heating.
Check charge of vessel. Re-
Faulty expansion
charge vessel to 3.5 bar or
vessel or lost charge
replace if necessary
5.
FAULT FINDING
Содержание Contract STI 300 indirect
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