hajdu ZF15 Manuel D'installation Et D'utilisation page 21

If you discover leakage from the interior of the tank or any other sign of irregular
operation, promptly disconnect the appliance from the electrical and water supply
network by pulling out the mains cable plug and using the closing valve.
1. Combined safety valve
At least every two months, blow off the valve by turning the blow-off button of the
safety valve (item 4, Figure 3-4) in the direction indicated by the arrow or lifting the
lever. This will clean the valve seat of any possible sand deposit, preventing its
adhesion. If the leakage does not stop when the heating is switched off, have the
appliance checked by a technician. We recommend to have it supervised annually.
2. Temperature regulator
The temperature of the water in the hot water tank can be continuously set from 35
to 80°C with the help of the rotary knob.
Energy saving
You can set the regulator to zero by turning the knob counter-clockwise until it
stops. Turn the control knob clockwise to increase the desired temperature.
At the * sign, you can ensures the frost protection of the appliance, except when the
unit is taken out of use or a power failure occurs. Frost protection does not apply to
the water supply network and assemblies.
In frost protection mode3, the water temperature may not fall under app. 7°C, while
energy consumption remains minimal. When the control knob is set to the start of
the two continuous lines, the tank supplies 40°C water. The 40°C setting means
energy-saving mode, where the heat loss is reduced by nearly 70%, compared to the
80°C setting, and the hot water obtained can be used without added cold water.
If the hot water need can be met using water of this
temperature, taking into account the volume of the
given tank, it is advised to operate the tank at 40°C.
The start of the three lines means 60°C and the end
means 80°C. When more water is needed, operate the
hot water tank at 60°C, and do not set the
temperature regulator to 80°C, unless it is absolutely
necessary.
There is significantly less scale deposit or corrosion,
when the temperature is set to either 40°C or 60°C. Control knob
20