MEGAF
LO H
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31
Table 2 - Fault Finding Chart
FAULT
POSSIBLE CAUSE
REMEDY
No hot water flow
1. Mains supply off
1. Check and open stop cock
2. Strainer blocked
2. Turn off water supply.
Remove strainer and clean (see
Section 8.3)
3. Cold Water Combination
Valve incorrectly fitted
3. Check and refit as required
Water from hot taps is
cold
1. DIRECT immersion
heater not switched on
1. Check and switch on
2. DIRECT immersion
heater thermal cut-out has
operated
2. Check. Reset by pushing
button. (See Diagram 7)
3. INDIRECT programmer
set to Central Heating only
3. Check. Set to a Domestic
Hot Water programme
4. INDIRECT boiler not
working
4. Check boiler operation. If fault
is suspected consult boiler
manufacturer's instructions
5. INDIRECT thermal cut-
out has operated
5. Check. Reset by pushing
button on cut-out. Check
operation of indirect thermostat
6. INDIRECT motorised
valve not connected
correctly
6. Check wiring and/or plumbing
connections to motorised valve
(see Diagram 9)
Water discharges
1. INTERMITTENTLY
from Expansion Relief
Valve
Expansion vessel charge
pressure has reduced below
3.5 bar
1. See Section 7.5 for re-
charging procedure
2. CONTINUALLY
a. Cold Water Combination
Valve Pressure Reducer not
working correctly
a. Check pressure from Cold
Water Combination Valve. If
greater than 3 bar replace
Pressure Reducer cartridge
b. Expansion Valve seat
damaged.
b. Remove Expansion Valve
cartridge. Check condition of
seat. If necessary fit new
Expansion Valve cartridge.
Water discharges from
T&P Relief Valve
1. Thermal control failure
NOTE water will be very hot
1. 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.
