14
GENERAL REQUIREMENTS
Guide to system
requirements
Water circulation system
Detailed recommendations for the
water circulation system are given in
BS 6798 and BS 5449: Part 1 (for
small bore and micro bore central
heating systems).
Pipework not forming part of the
useful heating surface should be
insulated to help prevent heat loss
and possible freezing, particularly
where pipes are run through roof
spaces and ventilated underfloor
spaces.
Draining taps must be located in
accessible positions which permit the
draining of the whole system
including the boiler and the hot water
system. Draining taps should be at
least 1/2 in. BSP nominal size and
be in accordance with BS 2879.
The boiler is suitable for use with
minibore or microbore systems.
Copper tubing to BS 2871: Part 1
should be used for water carrying
pipework. All capillary joints in the
DHW pipework must be made with
lead free solder.
Particularly where a new boiler is to
be fitted to an existing system, it is
good practice that the system is
thoroughly cleansed. This cleansing
should take place prior to the fitting
of the new boiler and be in
accordance with BS 7593.
For advice on the application of
system cleansers contact either
Sentinel, Betz Dearborn Ltd. Widnes,
Cheshire, WA8 8UD.
Tel: 0151 495 1861
or Fernox
Alpha-Fry Technologies
Tandem House
Marlow Way, Beddington Farm Road
Croydon CRO 4xS
Tel. 0870 601 5000
Fernox technical
help line 01799 550811
Filling and make up
The system should be filled with water
via a seperate filling point at a
convienient position on the heating
cicuit. The connection must be
removed when filling is completed.
Where local Water Authority
regulation does not allow temporary
connection, a sealed system filler
pump with break tank must be used.
The heating system will not be filled
automatically from the domestic hot
water side.
(Alternative methods of filling sealed
systems are given in BS 5449).
Pressure relief valve
A pressure relief valve is provided
with the boiler. This safety device is
required on all sealed C.H. systems
and is preset at 3 bar and provided
with a 15 mm compression connec-
tion for a discharge pipe, which must
be of no less than 15 mm in diame-
ter. The Pressure Relief Valve must not
be used for draining purposes.
Pressure gauge
This is factory fitted to the boiler and
indicates the primary circuit pressure
to facilitate filling and testing.
