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3.3.
Filling the system
When all the boiler connections have been completed, the CH system can be filled with water.
This must be done with caution, following these steps in sequence.
• Open the air purging valve on all the radiators and check the efficiency of the automatic boiler valve.
• Gradually open the boiler filling tap and check that all the automatic air valves work efficiently.
• Close all the radiator valves as soon as water starts to come out.
• Check on the water pressure gauge that the reading is 1-1.3 bar.
• Close the filling tap and open all the valves on the radiators to remove any residual air.
• Start the boiler and as soon as the system reaches the working temperature, stop the pump and repeat the air bleeding
procedure.
• Allow the system to cool down and the water pressure to return to 1-1.3 bar.
WARNING
As regards treating water in domestic heating systems, it is advisable to use specific products that are suitable for
multi-metal plants, in order to optimize performance and safety, preserve these conditions over time, ensure regular
operation of auxiliary equipment as well, and minimize energy consumption, in compliance with the applicable laws
and standards.
WARNING
The low water pressure safety switch will prevent the burner from being started when the water pressure is below
0.4÷0.6 bar.
The water pressure in the CH system must not be below 1÷1.3 bar. Restore the correct value as needed and while the
water in the system is cold.
The boiler pressure gauge shows the water pressure in the system.
WARNING
If the boiler is not used for a long time, the pump may not work.
BEFORE STARTING UP THE BOILER, PERFORM THE FOLLOWING PROCEDURE TO MAKE SURE THAT THE PUMP WORKS.
• Unscrew the protection bolt in the centre front section of the pump motor.
• Insert the tip of a screwdriver in the hole and rotate the circulation unit shaft clockwise.
• Once the unblocking operation has been completed, screw the protection bolt back on and check for water leaks.
When the protection bolt is removed, some water may flow out. Before re-installing the external housing of the boiler,
check that all internal surfaces are dry.
3.4.
Starting the boiler
3.4.1. Preliminary checks
Before starting the boiler, perform the following checks:
• The flue gas exhaust pipe and terminal must be installed as instructed. When the boiler is running, no combustion products
must leak from any of the gaskets.
• Supply power to the boiler must be 230 V – 50 Hz.
• The system must be filled with water (pressure reading on water gauge 1÷1.3 bar).
• All the stopcocks on the pipes must be open.
• The gas supplied to the boiler must be of the type for which the boiler is designed. If necessary, convert the boiler following
the instructions in subsection 3.6 - ADAPTATION TO OTHER GASES AND BURNER ADJUSTMENT. This operation must be carried
out by a qualified service engineer.
• The gas supply stopcock must be open.
• There must be no gas leaks.
• The main power switch must be on.
• The boiler safety valve must not be blocked.
• There must be no water leaks.
• The pump must not be blocked.
The boiler is equipped with a three-speed circulation pump corresponding to three different residual heads.
It is delivered with the circulation pump on the third speed setting.
If you wish to set a different speed, taking account of the water circulation requirements in the boiler (assured
by the water pressure switch) and the resistance properties of the system, check operation of the boiler in
all the conditions dictated by the features of the system (e.g. closure of one or more heating zones or of
thermostat-controlled valves).
3.4.2. Switching on and off
To switch the boiler on and off, refer to the Instructions for the User, in section 1.
