Bsi bs en 00656 2000 (2006)

BRITISH STANDARD

BS EN
656:2000
Incorporating
Amendment No. 1

Gas-fired central
heating boilers —
Type B boilers of
nominal heat input
exceeding 70 kW but
not exceeding 300 kW

The European Standard EN 656:1999, with the incorporation of
amendment A1:2006, has the status of a British Standard

ICS 91.140.10

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BS EN 656:2000

National foreword
This British Standard is the official English language version of
EN 656:1999, including amendment A1:2006. It partially supersedes
BS 5978-1, -2 and -3:1989 which will be withdrawn once the full series of boilers
standards being prepared by CEN/TC 109 have been adopted by BSI.
The start and finish of text introduced or altered by amendment is indicated in
the text by tags !". Tags indicating changes to CEN text carry the number

of the CEN amendment. For example, text altered by CEN amendment A1 is
indicated in the text by !".
The UK participation in its preparation was entrusted to Technical Committee
GSE/41, Non-domestic gas-fired central heating boilers, which has the
responsibility to:
—

aid enquirers to understand the text;

—

present to the responsible international/European committee any
enquiries on the interpretation, or proposals for change, and keep UK
interests informed;

—

monitor related international and European developments and
promulgate them in the UK.

A list of organizations represented on this committee can be obtained on
request to its secretary.
Cross-references
The British Standards which implement international or European
publications referred to in this document may be found in the BSI Catalogue
under the section entitled “International Standards Correspondence Index”, or
by using the “Search” facility of the BSI Electronic Catalogue or of British
Standards Online.
This publication does not purport to include all the necessary provisions of a
contract. Users are responsible for its correct application.

Compliance with a British Standard does not of itself confer immunity
from legal obligations.

Summary of pages
This document comprises a front cover, an inside front cover, the EN title page,
pages 2 to 116, an inside back cover and a back cover.
The BSI copyright notice displayed in this document indicates when the
document was last issued.
This British Standard, having
been prepared under the
direction of the Engineering
Sector Committee, was published
under the authority of the
Standards Committee and comes
into effect on 15 February 2000

© BSI 2006

ISBN 0 580 32062 6

Amendments issued since publication
Amd. No.

Date

Comments

16533

29 September 2006 See national foreword

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4.3 Type of technologies ..................................................................................................................... 20
4.3.1 gas condensing boiler .................................................................................................... 20
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5.16 Chemical composition of the condensate for low temperature boilers ...................................... 37
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