MDC XT12HR 2021, Руководство пользователя

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49
Plumbing
Water Heater Trouble Shooting
Gas Operation
Symptom Cause Remedy
When switching on, the heater does not
operate.
No 12 V DC supply voltage. Check the power supply (operation
voltage min. 10.5 V). Check the
Truma UltraRapid fuse (refer to
maintenance “Fuses”).
When switching on, the heater does not
operate, and
the red lamp lights up after
approx. 30 secs.
– Cowl cover fitted.
– Air in the gas supply.
– No gas supply.
– Incorrect gas pressure.
Remove cowl cover and / or clear
any obstruction.
Check gas valves and gas cylinder.
To unlock (and purge air), switch off
the appliance, wait 5 minutes, and
switch on again.
Heater operates for a prolonged
time and then the red lamp lights up.
Excess temperature
thermostat has responded.
Check water level, refill if required
(close drain valve).
To unlock, switch off the appliance,
wait 5 minutes, and switch on again.
Water Supply
Symptom Cause Remedy
Water drips from the P&T safety
valve. – Water pressure to high.
– Lime or dirt under the P&T safety
valve seat.
Check water pressure (max. 400 kPa),
use a pressure reducer
when connected to central water
supply.
Allow the appliance to cool and then
slowly raise the test lever (Fig. 2a –
4a) to flush the water system and
attempt to force dirt or foreign
matter out of the P&T safety valve
seat.
Replace P&T safety valve. This must
be performed only by a certified
service technician.
When opening the cold water tap,
hot water comes out.
– Hot water flows back through the
cold water supply.
-Fit a non-return valve in the cold
water supply (refer to installation
i nstructions “Water connection”).
-Non return valve faulty