Electrical; General; Mains Power Connection; New Complete System Installations - Worcester GREENSTAR 24 Installation, Commissioning And Servicing Instructions

Electrical

1
3
Fig. 37 Plume distance to opening
1 Opening in building
2 Flue discharge
3 Plume deflector
4 Minimum 1500mm from an opening in the building
Table 14 Key to figure 37
24
4
2
6720643895-119.1Wo
5 ELECTRICAL
5.1

GENERAL

CAUTION: Risk of electric shock
▶ Isolate the mains electrical supply before starting
any work and observe all relevant safety precautions.
The boiler is pre-fitted with a mains supply cable. Route
the cable through one of the holes adjacent to the flow
and return valves on the isolating valve bracket, leaving
some slack for movement of control panel.
FUSES
The appliance is protected by three fuses. They are located on the circuit
board (page 27).
Replacement fuses can be found on the back of the cover
( Fig. 39).
5.2

MAINS POWER CONNECTION

• The mains electrical supply to the boiler must be through either a
fused double pole isolator or a fused three pin plug and unswitched
socket situated, where practicable, adjacent to the boiler.
• The isolator must have a contact separation of 3mm minimum in both
poles.
• Any additional equipment connected to the boiler must not have a
separate electrical supply.
• External fuse rating 3A.
5.2.1

NEW COMPLETE SYSTEM INSTALLATIONS

If a new complete heating system installation is in a new build property
or is a first time installation in an existing property, heating systems must
conform to current building regulations Part L1a.
All new heating systems in dwellings must have at least two heating
zones. Each of these zones will be controlled by a thermostat and zone
valve.
An alternative would be individual electronically controlled TRVs. Hot
water supplied from a storage system would require separate time and
temperature control.
2
If the dwelling is over 150m , than a separate time and temperature
control for each zone is required.
All radiators must have TRVs fitted in all rooms except bathrooms and
rooms with room thermostats.
The exception to this are single storey, open plan dwellings where the
living area is more than 70% of the total useable floor area. Then this
type of dwelling can be controlled as one zone.
5.2.2

EXISTING INSTALLATIONS

For boiler replacements on an existing system, it is not necessary to zone
the upstairs and downstairs separately, compliance with the zone
requirements can be achieved by a single room thermostat or
programmable room thermostat.
While the system is drained down, TRVs must be fitted to all rooms
except the bathrooms and the room with the room thermostat.
5.3

ACCESS TO ELECTRICAL CONNECTIONS

Lower the control box into the service mode position to access all wiring
connections:
▶ Remove the outer casing ( page 21).
6 720 811 922 (2014/07)