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INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER BOSCH
8-716-106-252a (03.05)
11
CONDENSATE &
PRESSURE RELIEF PIPEWORK
CONDENSATE &
PRESSURE RELIEF PIPEWORK
CONDENSATE PIPEWORK:
The condensate pipe must be a minimum of
21.5mmØ polypropylene pipe.
The condensate pipework must fall at least
50mm per metre towards the outlet and should
take the shortest practicable route and not
exceed 3 metres outside the building.
The pipework must follow one of the options
shown opposite:
a - Internal waste drainage system
b - Soil/vent stack
c - External drainage system
d - External condensate absorption point
Use waterproof pipe insulation in exposed
positions and for external pipework
IMPORTANT: Condensate pipework must
not leak and must discharge into a
condensate trap filled with water before the
boiler is started to prevent the possibility of
potentially harmful flue products escaping
via the condensate route.
A -Condensate from boiler
B -Sink
C -21.5mmØ polypropylene condensate pipe
D -Gully
E -Internal soil and vent stack
F - Condensate trap (75mm min)
G -300mm x 100mmØ sealed plastic tube
H -Ground level
J - Drainage holes 50mm from base of tube
(12mmØ at 25mm centres) facing away from
building
K -Limestone chippings
PRESSURE RELIEF PIPEWORK:
IMPORTANT: The pressure relief valve is a
safety device for the boiler and if activated
may discharge boiling water or steam
through the relief valve drain pipe.
Care should taken when siting the outlet
pipe so that it does not cause an obstruction
or discharge above a window, entrance or
other public access where it could cause a
hazard.
The pressure relief drain pipe (M) should be
at least 15mm diameter copper pipe and run
downwards away from the boiler and discharge
away from any electrics or other hazard,
preferably to an external drain or soakaway.
Pipe (M) should be finished with a partial bend,
near the outlet to face the external wall (as
shown) to help prevent freezing.
Use waterproof pipe insulation in exposed
positions and for external pipework.
L - Outside wall
M - Drain pipe
N - External drain
M
N
L
M
Invert
450 min
.
75mm
min.
75mm min.
a
b
E
A
A
B
C
D
C
F
F
75mm min.
c
D
A
C
F
25mm
min.
400mm
min.
500mm min.
d
G
K
J
H
75mm min.
A
C
F
