20
20
control again as soon as the high-limit thermostat is
deactivated.
If the overheating cut-out is activated, it must be reset
manually after the water has cooled down. Upon
resetting, the water heater will resume its operation in the
usual way.
2.5
Setting the nominal load
This section is only applicable, if the heater has been
equipped with a gas-fired burner.
Setting the nominal load is always necessary
because the load may vary with the various ventilator
burners. The burners have not yet been set to the
right load by the manufacturer.
Setting the nominal load and checking the correct
gas/air ratio must be carried out in accordance with
the instruction manual for the front-mounted burner.
The burner pressures to be set for Riello front-mounted
burners are shown in table 1.3.2
2.6
Conversion to another gas type
This section is only applicable, if the heater has been
equipped with a gas-fired burner and
conversion of the burner is permissible.
If the heater has to function on a gas category (LP-gas or
natural gas) other than the gas set as standard (ex
works), the heater must be converted to the applicable
gas category by means of the conversion kit(s) to be
ordered. Only an authorised installer may convert the
heater.
2.7
Maintenance
The heater must be checked and cleaned regularly (at
least once a year) by an accredited installer, so that
correct operation is guaranteed. The bar burners, control
and safety valves, the glow igniter and anodes must also
be checked
.
2.8
Anode
The life of the anode is determined by the quality and
quantity of the water flowing through the heater.
Therefore, we recommend that the anode is checked
regularly - preferably simultaneously with an internal
inspection of the glass lined tank. In order to determine
the frequency with which the anodes must be replaced,
the water side of the boiler must be checked three
months after installation. The anodes must be replaced if
more than 60% has dissolved at any point on their length.
To inspect the tank:
1. Close the cold-water inlet tap;
2. Empty the heater completely by opening the drain
valve;
3. Remove the covering plates on the heater’s outer
jacket;
4. Remove the access cover plates form the tank by
unscrewing and removing the bolts and washers,
(see figure 6);
5. To ensure watertightness of the access covers the
rubber O-rings must be replaced when the access
covers are refitted, (see figure 6).
To inspect the anodes:
1. Remove the draught diverter;
2. Unscrew the fastening screws on the lid edge;
3. Remove the lid. The hexagonal heads of the anodes
are now visible, (see figure 7);
4. Unscrew the anodes with the appropriate spanner
and replace with new anodes if required. Attention:
the anodes must make contact with the tank (metal
on metal). If the tank and the anodes are separated
electrically (as a result of the sealing material used),
the anode cannot function. This could have a
negative effect on the operating life of the tank;
5. Assemble everything in reverse order;
6. Fill the heater and test.
Figure 6: Inspection hatches.
Figure 7: Anodes
