A.O. Smith TWI 35-200 Troubleshooting guide

Twister
Condensing Stainless Steel
Water Heater
TWI 35-200/45-200
Installation, User and Service Manual
0313279 / R1.1 0819 / EN

A.O. Smith Water Heaters
Unit B7-B8 Armstong Mall
Southwood Business Park
Farnborough Hampshire
GU14 ONR UK
T : 0870 267 6484
[email protected]
www.aosmith.co.uk
A.O. Smith Europe
De Run 5305
PO Box 70
5500 AB Veldhoven
The Netherlands
Data is subject to change.

Preface
Copyright
Copyright © 2018 A.O. Smith Water Products Company
All rights reserved.
Nothing from this publication may be copied, reproduced and/or published by means of
printing, photocopying or by whatsoever means, without the prior written approval of
A.O. Smith Water Products Company.
A.O. Smith Water Products Company reserves the right to modify specifications in this
manual.
Trademarks
Brand names in this manual are registered trademarks of their respective owners.
Warranty
Refer to the appendix Warranty (see 13.7) for the warranty provisions.
Liability
User
A.O. Smith accepts no liability when the water heater is not used correctly and requires
the user to:
•Read this manual carefully and obey the instructions.
•Ask your installation engineer for advise about the use of the water heater.
•Make sure that the service and maintenance activities are done by a qualified
engineer.
•Store the manual, in good condition, near the water heater.
Installation engineer
A.O. Smith accepts no liability when the water heater is not used correctly and requires
the installation engineer to:
•Read this manual carefully and obey the instructions.
•Make sure that the entire water heater installation complies with the applicable
regulations (on page 4).
•Make sure that the water heater is tested before the installation is taken into use.
•Explain the correct use to the user.
•Notify the user when service and maintenance activities are necessary.
•Make sure that you hand over all applicable manuals.
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Supplier
The Twister water heater is designed in accordance with the applicable regulations. The
water heater is delivered with the CE-marking and all necessary documentation to obey
these regulations. See the compliance section. (on page 4)
A.O. Smith accepts no liability for claims from third parties when:
•The instructions for the correct installation of the water heater are not obeyed.
•The instructions for the correct use of the water heater are not obeyed.
•The water heater did not have maintenance on the correct maintenance interval.
For more information, refer to the General Terms of Sales. These are available on request,
free of charge.
We believe that this manual provides you with accurate and complete descriptions of all
relevant components. If you, nonetheless find errors or inaccuracies in this manual, please
inform A.O. Smith. This helps us to further improve our documentation.
Compliance
To safely produce domestic hot water, the design and construction of the Twister water
heaters is in accordance with:
•the European Regulations 2016/426 on appliances burning gaseous fuels (GAR).
•the European Standard for Gas–fired storage water heaters for the production of
domestic hot water (EN89).
•The European ECO-Design Directive.
•The European Energy Labeling Directive
Refer to the appendix Declaration of conformity.
Regulations
It is law that all gas appliances are installed by competent persons, in accordance with The
Gas Safety (Installation and Use) Regulations 1998. Failure to install appliances
correctly could lead to prosecution. It is in your own interest, and that of safety, to ensure
that this law is complied with. The installation of the equipment MUST be in accordance
with the relevant requirements of the Gas Safety Regulations, Building Regulations,
I.E.E. Regulations and the bylaws of the local water undertaking.
In addition, the installation should follow the relevant guidance offered in the following
documents. It is not practical to list all relevant information due to continuous changes but
emphasis is placed on the following documents, as failure to comply with the guidance
given will almost certainly result in an unsatisfactory installation:
•British Standards (BS)
•Institute of Gas Engineers and Managers (IGEM) Publications
•CIBSE Guides
•Clean Air Act
•H.S.E Guidance
Note
Manufacturer's notes must not be taken in any way as overriding statutory obligations.
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Contact information
If you have any comments or questions, please contact:
A.O. Smith Water Products Company
Adress: PO Box 70
5500 AB Veldhoven
The Netherlands
Telephone: 0870 - AOSMITH (free)
0870 - 267 64 84
General: [phone]
Fax: [phone]
E-mail: [email protected]
Website: www.aosmith.co.uk
In the event of problems with your gas, electricity or water supply connections, contact
your (energy/water) supplier.
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About this manual
Scope
This manual gives information about safe and correct use of the water heater and how
installation, maintenance and service activities have to be done correctly. You must obey
the instructions in this manual.
Caution
Read this manual carefully before you start the water heater. It can cause personal injury
and damage to the water heater when you do not read the manual and/or do not obey
the instructions.
The purpose of this manual is to:
•describe the working principles and layout of the water heater
•explain the safety devices
•highlight possible hazards
•describe the use of the water heater
•describe the installation, service and maintenance of the water heater
This manual has two parts:
•An User part that describes the correct usage of the water heater.
•An Installation, Maintenance and Service part, that describes the correct installation
and maintenance procedures.
Target group
The information in this manual applies to three target groups:
•users
•installation engineers
•service and maintenance engineers
The User part is intended for the (end) users. The Installation, Maintenance and Service
part is intended for the installation engineers and the service and maintenance engineers.
Notation conventions
This manual uses the following text conventions:
•Numbers between parentheses e.g. (1), refer to elements in a figure that are
described by the text.
•Buttons are always shown between brackets, for example: [ACCEPT], [BACK].
•Cross-references to sections, tables, figures etc. are underlined and written as (see
"..."). In the digital version, the cross-references function as hyperlinks that can be
used to navigate through the manual by clicking on them. Example: Safety (see 2).
This manual contains the following text styles/symbols for situations that may endanger
users/engineers, cause damage to equipment or need special attention:
Note
A note gives more information on a topic.
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Caution
Obey the caution instructions to prevent damage of the water heater.
Warning
Obey the warning instructions to prevent danger of personal injury, and serious damage
to the water heater.
Document identification
Article number Language Version
0313279 UK 1.1
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Table of Contents
Preface........................................................................................ 3
Copyright.......................................................................... 3
Trademarks....................................................................... 3
Warranty...........................................................................3
Liability.............................................................................3
Compliance....................................................................... 4
Regulations....................................................................... 4
Contact information............................................................ 5
About this manual....................................................................... 7
Scope............................................................................... 7
Target group......................................................................7
Notation conventions.......................................................... 7
Document identification.......................................................8
User part.................................................................. 13
1 Introduction.............................................................................. 15
2 Safety........................................................................................17
3 Interface................................................................................... 19
3.1 Operator interface............................................................ 19
3.1.1 Control Switch..................................................................19
3.1.2 Display............................................................................19
3.1.3 Display buttons................................................................ 20
3.2 Status of the water heater................................................. 21
3.2.1 Operating modes.............................................................. 22
3.2.2 Error conditions................................................................22
4 Use............................................................................................ 23
4.1 Turn on the water heater................................................... 23
4.1.1 Switch to ON mode........................................................... 23
4.1.2 Set the water temperature.................................................23
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4.2 Turn off the water heater................................................... 24
4.2.1 Turn off for a short period.................................................. 24
4.2.2 Isolate from the mains...................................................... 24
4.2.3 Turn off for a long period................................................... 24
Installation, Maintenance and Service part.............. 25
5 Introduction.............................................................................. 27
5.1 About the water heater..................................................... 27
5.2 Working principle..............................................................27
6 Safety........................................................................................29
6.1 Safety instructions............................................................29
6.2 Instructions on the water heater.........................................30
6.3 Safety devices..................................................................31
6.4 Environmental aspects...................................................... 33
6.4.1 Recycling.........................................................................33
6.4.2 Disposal.......................................................................... 33
7 Water heater............................................................................. 35
7.1 Structure of the water heater............................................. 35
8 Installation............................................................................... 37
8.1 Packaging........................................................................37
8.2 Conditions....................................................................... 37
8.2.1 Ambient conditions........................................................... 37
8.2.2 Maximum floor load.......................................................... 37
8.2.3 Water composition............................................................ 37
8.2.4 Working clearances...........................................................38
8.3 Installation diagram..........................................................38
8.4 Water connections............................................................ 39
8.4.1 Cold water connection....................................................... 39
8.4.2 Hot water connection........................................................ 40
8.4.3 Circulation connection....................................................... 40
8.5 Condensate drain............................................................. 40
8.6 Gas connection.................................................................40
8.7 Venting system................................................................ 41
8.7.1 C13/C33 concentric systems.............................................. 43
8.7.2 C13/C33 parallel systems.................................................. 45
8.7.3 C43/C53/C63 systems.......................................................47
8.8 Electrical connections........................................................ 48
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