MDC XT12HR 2021, Owner'S Manual

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Residues of frozen water can prevent filling if there is a frost. The water heater can be defrosted by switching on
the heater for a short period (max. 2 minutes). Frozen pipes can be defrosted by heating the room.
•
If just the cold-water system is being used, without water heater, the heater tank is also filled up with
water. To avoid damage through frost, water must be drained by means of the drain valve, even if the
heater has not been used. As an alternative, two shut-off valves, resistant to hot water, can be fitted in
front of the cold and hot water connection.
Pressure and Temperature Relief Valve (P&T safety valve)
• Risk of scalding injury from hot water and/or tampering with the P&T safety valve!
•
Do not actuate the P&T safety valve as long as the appliance is still hot.
•
Do not place a plug or reducing coupling in the discharge pipe (Fig. 2a - 4b) of the P&T safety valve.
• Do not operate the water heater without a functioning P&T safety valve - this could cause an
explosion.
The P&T safety valve (4) is a safety component and must not be removed for any reason other than replacement.
The P&T safety valve is not serviceable; if defective it must be replaced (failure to reuse an old P&T safety valve). It
must be replaced by a certified service technician.
Tampering with the P&T safety valve will void the warranty.
4 P&T safety valve
4a Test lever
4b Discharge pipe
Draining the Water Heater
•
If the vehicle is not used during periods of frost, it is essential that the Truma UltraRapid be emptied.
•
Disconnect power for water pump (main switch or pump switch).
•
Allow the appliance to cool down.
•
Open hot water taps in bathroom and kitchen.
• Open drain valve (Fig.2 - 3). Lever in the “f” position (drain). The water heater is now drained directly
to the outside via the drain valve (3).
•
Check that the water has been completely drained (14 litres).
S witching On Gas Operation
Never operate the heater without water in it!
If the wall cowl is positioned close to an opening window (or hatch) – in particular directly under it –
the window must remain closed when the water heater is in use (see warning plate).