Table Of Contents; Introduction - Alpha CD25C Installation And Servicing Instructions

CONTENTS
1 Introduction ....................................... 2
2 Technical data ................................... 3
3 General boiler information .................. 7
4 Installation ......................................... 13
5 Commissioning ................................. 19
6 Boiler operation ................................. 22
7 Routine servicing ............................... 23
1

INTRODUCTION

The Alpha CD range of high efficiency condensing boilers are wall mounted, fan assisted room-sealed combination boilers.
The burner is lit electronically and the heat output is controlled by a modulating fan and gas valve.
The CD25C, CD28C and CD35C are combination boilers providing both central heating and domestic hot water at mains
pressure.
The boilers are supplied with a pump, pressure relief valve, expansion vessel and pressure gauge fully assembled and tested.
They are designed for use with a fully pumped, sealed and pressurised central heating system using only Natural gas.
The CD25C boiler is suitable for central heating loads of between 5.5 and 19.5 kW (18 766 and 66 550 Btu/h).
The CD28C boiler is suitable for central heating loads of between 6.3 and 25.9 kw (21 496 and 88 400 Btu/h).
The CD35C boiler is suitable for central heating loads of between 7.8 and 30.3 kw (26 614 and 103 400 Btu/h).
The maximum output available for domestic hot water is 24.3 kW (84 800 Btu/h), capable of providing 9.6 litres/min for the Alpha
CD25C boiler, 28.7 kW (97 900 Btu/h), providing 11.4 litres/min for the Alpha CD28C boiler and 34.6 kW (118 100 Btu/h), providing
14.2 litres/min for the Alpha CD35C boiler, all with a temperature rise of 35°C.
IMPORTANT
It is the law that all gas appliances are installed by a competent person, ie CORGI registered personnel, in accordance with
the following recommendations:-
Current Gas Safety (Installation and Use) Regulations
All current Building Regulations issued by the Department of the Environment, i.e. Approved Document L1.
Building Standards (Scotland) (Consolidation) Regulations issued by the Scottish Development Department
UK Water Regulations/Byelaws (Scotland)
Health & Safety Document No. 635 (The Electricity At Work Regulations 1989)
The installation should also be in accordance with the following British Standard Codes of Practice:-
BS 5440:1:2000 Flues
BS 5449:1990 Forced circulation hot water systems
BS 5546:2000 Installation of hot water supplies for domestic purposes
BS 6700:1997 Design, installation, testing and maintenance of services supplying water
BS 6798:2000 Installation of gas fired hot water boilers
BS 6891:1998 Gas installation
BS 7593:1992 Code of Practice for treatment of water in heating systems
BS 7671:2001 Requirements for electrical installations, IEE Wiring Regulations
Reference should be made to DEFRA document 'Guide to condensing boiler installation assessment procedures for dwellings'.
If installation is in a timber framed building, refer to the Institute of Gas Engineers document IGE/UP/7.
This appliance meets the requirements of IPX4D, ie degree of protection against moisture.
Failure to install this appliance correctly could lead to prosecution. It is in your own interest and that of safety to ensure that the
law is complied with.
Manufacturer's instructions must NOT be taken in anyway as over-riding statutory obligations.
Notes: 1. Ensure that the Benchmark Checklist has been completed after the boiler has been installed and commissioned.
2. It is the law that all boiler installations are registered by the installer through the CORGI Gas Work Notification
Scheme.
3. The boiler must only be used with Alpha CD condensing flue components.
Alpha CD25C/28C/35C - Contents/Introduction
2
8 Component replacement ................... 25
9 Wiring diagrams ................................ 31
10 Fault finding ...................................... 33
11 Short parts list ................................... 37
12 Benchmark Checklist ........................ 38
13 Service record ................................... 39