Worcester 27i System Compact User Manual

PRE-INSTALLATION
Greenstar i System Compact - 6 720 807 726 (2013/05)10
SEALED PRIMARY SYSTEM:
• The CH sealed system must be filled using a WRAS approved filling
loop or comply with figure 2 for system fill.
• Where the system volume is more than 100 litres or exceeds 2.65 bar
at maximum heating temperature, an extra expansion vessel (2) must
be fitted as close as possible to the appliance in the central heating
return.
• Pressurise the extra expansion vessel (2) to the same figure as the
expansion vessel built into the appliance.
• Do not use galvanised pipes or radiators.
SYSTEM FILL
Fig. 2 System fill
Fig. 3 Additional expansion vessel
[1] Appliance expansion vessel - CH
[2] Extra expansion vessel - CH return
[3] Pressure relief discharge
OPTIONAL DIVERTER VALVE
This boiler is designed to operate on a sealed system only. The boiler will
require a second return pipe from the water cylinder to the wall
mounting frame and terminate in 15mm copper pipe.
3.3.1 S AND Y PLAN SYSTEMS
3.3.2 EXISTING INSTALLATIONS
S PLAN LAYOUT
Y PLAN LAYOUT
SYSTEM LAYOUT WITH OPTIONAL INTERNAL DIVERTER VALVE
(NOT SUPPLIED WITH BOILER)
[1] Diverter valve
[2] Radiator valve (flow)
[3] Lock shield valve (return)
[4] Bypass
3.3.3 NEW INSTALLATIONS
S PLAN PLUS LAYOUT
NOTICE: Artificially softened water must not be used to
fill the central heating system.
The boiler is equipped with an internal by-pass.
The internal bypass is not intended to be a substitute for
an external system bypass.
An external automatic bypass should be used if the
system flow can be significantly adjusted or stopped by
zone valves and thermostatic radiator valves (TRV).
CV = Check Valve
SV = Stop Valve
SV SV
Test point
Temporary hose
Hose union
CV
CV
Heating
return
Mains
supply
SYSTEM MAKE UP
AA = Auto Air vent
CV = Check Valve
SV
CV
AA
Make up
vessel
Heating
return
1000 mm (39 in)
above the highest
point of the system.
Fill point
6720644743-08.1Wo
1
2
3
6720644743-09.1Wo
NOTICE: Automatic bypass
▶ An automatic bypass valve is required when fitting an
S-plan type system with two-port valves.
NOTICE: Drain cock
▶ A drain cock should be fitted at the lowest point(s) of
the heating circuit and beneath the appliance.
3
2
1
4
M
M
3
2
1
M
6720646609-33.1Wo
Heating flow
Cylinder return
Cylinder flow
Heating return
F
R
3
2
F
R
3
2
1
4
M
MM

Worcester 27i System Compact Specifications

General

Brand	Worcester
Model	27i System Compact
Category	Boiler
Language	English