Electrical connection
27
Worcester Commercial Boiler Series – 6720814332 (2019/04)
▶ Connect the connection pipe of the expansion vessel to the
connection point.
Fig. 45 Expansion vessel connection
5.12
Mounting the back panel insulation
▶ Hook the insulated rear panel of the pump group into the boiler.
Fig. 46 Mounting the insulated rear panel
6
Electrical connection
CAUTION:
Risk of electric shock.
▶ Always isolate the boiler from the power supply before working on the
electrical parts. Guard against unintentional re-connection.
NOTICE:
Short circuit.
▶ Only use original cables if they must be replaced.
In order to commission and electrically isolate the boiler, the mains
isolator and therefore the socket (230 V AC, 50 Hz) must be accessible
at all times. The socket must be earthed (earthing contact).
Use a 2-wire power cable with 0.4 - 0.8 mm
2
cross-section for all
24 V AC connections on the terminal strip.
▶ When establishing the electrical connections, also observe the
documentation and wiring diagram of the accessory being connected
(
chapter 2.12, page 10).
6.1
Control principle
The boiler is suitable for control according to the principles of room
temperature-dependent and weather-dependent control.
• In the case of room temperature-dependent control, the user
interface in the reference room controls the temperature required
within it (room temperature-dependent controller). In order to
control the temperature correctly, radiators must be equipped with
manual radiator valves or the thermostatically controlled radiator
valves must be fully open (
figure 47).
• With weather-dependent control, the temperature in all rooms is
controlled by thermostatically controlled valves mounted on the
radiators. The controls can be installed in any location (
figure 48).
Fig. 47 Control principle of room temperature-dependent control
[1]
Boiler
[2]
Room temperature-dependent controller
[3]
Radiator valve
[4]
Thermostatically controlled radiator valve (TRV)
[5]
Other rooms
[6]
Living space
[7]
Installation location
0010010000-001
1
0010010001-001
0010010002-001
1
2
7
6
5
4
3
