Gas Installation - Hamworthy WESSEX-HE 200 Installation, Commissioning And Servicing Instructions

British Standards Codes of Practice
BS 6891: Installation of low-pressure gas pipework of
up to 28mm (R1) in domestic premises. (For larger
installations see UP/1, UP/1A and UP/2 below).
BS 6644: Installation of Gas Fired Hot Water Boilers -
60kW to 2MW.
BS 6700: Design,
maintenance of services supplying water for domestic
use.
BS 6880: Code of practice for low temperature hot
water heating systems of output greater than 45kW.
BS 3456: (CEE 10 Part 1, CEE 11 Part 1) Electrical
Standards.
CP 342: Centralised hot water supply.
Part 2: Buildings other than individual dwellings.
Institution of Gas Engineers Publications
IGE/UP/1: Soundness
industrial and commercial gas installations.
IGE/UP/1A: Soundness testing and direct purging of
small low pressure industrial and commercial Natural
Gas installations.
IGE/UP/2: Gas installation pipework, boosters and
compressors in industrial and commercial premises.
IGE/UP/10: Installation of gas appliances in industrial
and commercial premises. Part 1: Flued appliances.
Health and Safety Executive
Guidance Note PM5 - Automatically Controlled Steam
and Hot Water Boilers.
CIBSE Publications
CIBSE Guide
It is impractical in this document to specify all relevant
information, but the following extracts from the above
references are emphasized since failure to comply
with these requirements will almost certainly result in
an unsatisfactory installation.
3.2 Feed Water Quality - If the boiler feed water has
a high degree of hardness, it is recommended that
the water be treated to prevent precipitation of scale
or sludge in the boiler water passageways. Details of
additives can be obtained
manufacturer of water treatment products or the local
Water Authority.
It should be noted however, that even if the boiler
water were of average hardness, not requiring
HAMWORTHY HEATING LTD
installation, testing
testing and purging
from any reliable
WESSEX-HE 200 BOILER
treatment, subsequent draining of the system for
repair or constant make-up water due to an
undetected leak would cause additional deposits and
gradual build-up of scale. It is essential therefore,
that leaks are attended to promptly and draining is
kept to an absolute minimum.
It is recommended that the system be flushed out at
least twice with hot water before any water treatment
is added. If any doubt exists regarding the internal
and
cleanliness of an old system, consideration should be
given to the fitting of a coarse filter in the return
pipework to the boilers.
3.3 Adequate Water Flow
Also refer to section 8.7.
The Hamworthy Wessex HE boiler is designed as a
quick response, low water content unit, to run
continuously with minimum or no operating problems.
Care should be taken in the initial design and layout
having due regard for adequate water flow through
the boilers and the influence of any control systems in
the pipework.
of
NOTE! The Standards Authority recommends a
minimum return temperature of 50°C in all heating
systems other than condensing boilers.
3.4 Time Clock Control
In order to avoid local overheating and progressive
calcium deposition at zero flow conditions where
boilers are operated by time clocks, provision should
be made for a 3 minute circulating pump over-run
after the last boiler has ceased firing.
NOTE! Time clocks should not interrupt live, neutral
or earth connections. External voltage MUST NOT
be applied to remote stop/start terminals C5 and C6.
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500001008/K