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8.4. Water circulation and water tank
8.4.1. Pressure relief valve
Your installer has installed a pressure relief valve near the cold water connection on
the domestic hot water tank to protect the water tank against excessive pressures
when the domestic water expands during the heating process.
The back pressure valve (check valve), which is installed in front of the pressure relief
valve on the cold water pipe, prevents water from the tank flowing back into the cold
water pipe. Therefore, the pressure in the water tank rises to the maximum setting of
the pressure relief valve and the pressure relief valve opens. The redundant water dis-
charges. If the pressure relief valve did not open, the water tank would burst.
The pressure relief valve must operated regularly to remove lime deposits and to ver-
ify that it is not blocked. It is tested by pressing the lever/turning the handle on the
pressure relief valve while checking that water discharges. Damages due to a faulty
pressure relief valve are not covered by the warranty.
Please note that water may drip from the discharge pipe of the pressure-relief valve
due to heating of the water.
8.4.2. Anode
In order to prevent corrosion of the enameled hot water tank, a magnesium anode is
installed behind the front panel at the top half of the water tank.
The anode has a life expectancy of approximately 2-5 years depending on the water
quality.
It is recommended to inspect the anode every year.
1) Disconnect the electrical power supply or pull out the power plug.
2) Remove the plastic front cover. This allows access to the anode.
3) Disconnect the wire connection between the anode and the tank (see pictures
below).
4) Insert a multimeter (range mA) between the anode and the tank. Anode current >
0.3 mA: Anode is active and ok. Anode current < 0.3 mA: Anode should be checked
and possibly be replaced.
5) Reconnect the wire connection between the anode and the tank. Close the front
cover and switch on the unit.