Worcester Greenstar FS 30CDi Regular Instruction Manual page 11

S PLAN LAYOUT
N
B C
150mm max.
A
Y PLAN LAYOUT
N
B C
150mm max.
A
SEALED SYSTEM LAYOUT
N
J
K
A
I
Mains cold water
L
A - Boiler.
B - Heating vent (min. Ø22mm).
C - Primary cold feed (min. Ø15mm).
D - Diverter valve.
E - Pump.
F - Automatic by-pass.
G - Radiator valve (flow).
INSTALLATION & SERVICING INSTRUCTIONS
8 716 115 216b (09.2008)
M M
min. 250mm min. 250mm
G
D
F
E
M M
min. 250mm min. 250mm
G
D
E
Hot water flow
G
D
Heating
return
Cylinder return
H - Lockshield valve (return).
I - Expansion vessel.
J - Pressure gauge.
K - Relief valve.
L - Stop valve.
M - Static head.
N - Feed & expansion cistern.
WATER SYSTEMS & PIPEWORK
S & Y PLAN OPEN VENT PRIMARY SYSTEM:
Generally a by-pass is not necessary on a Y plan
system as one of the parts is open to flow.
• The feed and expansion cistern (N) must
be positioned to provide a static head (M)
H
of at least 250mm above the highest point
in the heating system.
• The heating vent (B) and cold feed (C)
pipes must rise continuously from the
appliance.
• The heating vent pipe (B) must be at least
Ø22mm.
• No valve shall be fitted in the heating vent
pipe (B) or the cold feed and expansion
pipe (C).
H
FULLY PUMPED SEALED PRIMARY SYSTEM:
• A pressure relief valve (K) (spring loaded
safety valve set to operate at 3 bar) must
be fitted to the heating return pipe as close
as possible to the boiler.
• An expansion vessel (I) must be fitted to
the heating return pipe close to the boiler
and pressurised for the system volume
according to the instructions supplied with
H
the vessel.
• A pressure gauge (J) (3 bar min.) must be
fitted to the heating return pipe.
• An automatic air vent must be fitted.
• Stop valve (L) must be a fixed cylinder
type or sealed systems approved
connection.
Heating flow
WATER SYSTEMS & PIPEWORK
9