8
2.8.
W
ATER
C
ONNECTIONS
Legend:
A = Central Heating Flow
E = Central Heating Return
B = Domestic Hot Water Outlet
H = Condensate discharge
C = Gas Inlet
I = Safety valve discharge
D = Domestic Cold Water Inlet
J = Drain valve
Central Heating
Detailed recommendations are given in BS 6798:1987 and BS 5449-1:1990, the
following notes are given for general guidance.
P
IPE
W
ORK
:
Copper tubing to BS EN 1057:1996 is recommended for water pipes. Jointing
should be either with capillary soldered or compression fittings.
Where possible pipes should have a gradient to ensure air is carried naturally to air
release points and water flows naturally to drain taps.
The appliance has a built-in automatic air release valve, however it should be
ensured as far as possible that the appliance heat exchanger is not a natural
collecting point for air.
Except where providing useful heat, pipes should be insulated to prevent heat loss
and avoid freezing.
Particular attention should be paid to pipes passing through ventilated spaces in
roofs and under floors.
B
Y
-
PASS
:
The appliance includes an automatic by-pass valve, which protects the main heat
exchanger in case of reduced or interrupted water circulation through the heating
system, due to the closing of thermostatic valves or cock-type valves within the
system.
S
YSTEM
D
ESIGN
:
This boiler is suitable only for sealed systems.
D
RAIN
C
OCKS
:
These must be located in accessible positions to permit the draining of the whole
system. The taps must be at least 15mm nominal size and manufactured in
accordance with BS 2870:1980.
S
AFETY
V
ALVE
D
ISCHARGE
:
The discharge should terminate facing downwards on the exterior of the building in
a position where discharging (possibly boiling water & steam) will not create danger
or nuisance, but in an easily visible position, and not cause damage to electrical
components and wiring.
The discharge must not be over an entrance or a window or any other type of
public access.
C
ONDENSATE
D
ISCHARGE
:
The condensate discharge hose from the boiler must be inserted by at least 50 mm
into a suitable acid resistant pipe - e.g. plastic waste or overflow pipe. The
condensate discharge pipe must have a continuous fall and preferably be installed
and terminated within the building to prevent freezing.
The discharge pipe must be terminated in a suitable position:
V
IEW OF THE
B
OILER
C
ONNECTIONS
A
C
B
D
E
H
I
J
J
F
IG
. 2.4
A
C
E
H
I
27 MFFI
27 RFFI
