Guide To System Requirements; Water Circulation System; Filling And Make Up; Pressure Relief Valve - Vaillant 824/2 E Instructions For Installation Manual

requirements of BS 1363. Alternatively, a 3 Amp. fused
doublepole switch with a 3 mm contact separation on
both poles may be used.
Important!
This appliance must be earthed.

4.8 Guide to system requirements

4.8.1 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
all 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, GE Betz. Widnes, Cheshire,
WA8 8UD.
Tel: 0151 420 9595
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

4.8.2 Filling and make up

The system can be filled using the built in filling loop
(turboMAX plus only) or via a separate filling point fitted
at a convinient position on the heating circuit
(thermoCOMPACT). 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.
Instructions for Installation and Servicing turboMAX plus and thermoCOMPACT R1
Supplied By www.heating spares.co Tel. 0161 620 6677
General Requirements 4
(Alternative methods of filling sealed systems are given
in BS 5449).

4.8.3 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 connection for a discharge pipe, which
must be of no less than 15 mm in diameter. The Pressure
Relief Valve must not be used for draining purposes.

4.8.4 Pressure gauge

This is factory fitted to the boiler and indicates the
primary circuit pressure to facilitate filling and testing.

4.8.5 Expansion vessel

The 15 and 20 kW thermoCOMPACT boilers as well as
the 24 kW turboMAX plus boiler incorporate a 6 litre
expansion vessel which is suitable for a sealed heating
system with a maximum water content of 60 litres. A
10 litre expansion vessel kit is available as an optional
accessory for for the turboMAX plus 24 kW boiler and
the 15 and 20 kW thermoCOMPACT boilers.
The 28, 37 turboMAX plus and 24, 28, 37 kW
thermoCOMPACT boilers incorporate a 10 litre expansion
vessel which is suitable for a sealed heating system with
a maximum water content of 100 litres.
If the nominal capacity of the built in expansion vessel is
not sufficient for the heating system (for instance in
case of modernization of old open systems) an
additional expansion vessel can be installed external to
the boiler. It should be fitted in the return pipe as close
as possible to the boiler in accordance with BS 5449:
Part 1.
Guidance on the sizing of an additional expansion vessel
is given in Table on page 14.
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