Alpha CD28X User Manual

Installation and Servicing
Instructions
Alpha CD25X/28X
Range of Wall Mounted, Fan Assisted, Room Sealed,
Gas Fired, High Efficiency Condensing Combination Boilers
Alpha CD25X G.C. No. 47 532 39
Alpha CD28X G.C. No. 47 532 37
British Gas
Service Listed
For use with Natural Gas only
Leave these instructions with the User
Nepicar House, London Road,
Wrotham Heath, Sevenoaks,
Kent TN15 7RS
For Technical help or for Service call ...
ALPHA HELPLINE
Tel: 0870 3001964
0051

Alpha CD28X Specifications

General

ERP Rating	A
DHW Output (kW)	28
Flow Rate (l/min)	11.4
Output (kW)	28
Boiler Type	Combi
Mounting	Wall

Summary

Alpha Boiler Technical Data

Boiler Installation Procedures

Boiler Fitting and Pipework Connection

Instructions for fitting the boiler and connecting pipework.

Flue System Installation

Procedure for installing the flue system components.

Electrical Connections and Clock Kit

Connecting mains supply and installing an optional clock kit.

Boiler Commissioning Process

Gas Tightness and Supply Testing

Safety checks for gas tightness and supply.

Initial Lighting and Burner Pressure Checks

Steps for initial boiler ignition and verifying burner pressures.

Boiler Operation Modes

Routine Boiler Servicing

Pre-Servicing Checks and Notes

Key checks and notes to follow before performing routine servicing.

Component Replacement Guide

Burner Component Replacements

Replacing electrodes, main burner, and burner injector.

Fan, Ignition, and Gas Valve Replacements

Heat Exchanger and Flow Switch Replacements

Pressure Relief Valve and DHW Heat Exchanger

Wiring Diagrams

Boiler Fault Finding

Initial Fault Diagnosis Checks

Initial diagnostic checks for common boiler faults.

Central Heating Troubleshooting Sequence

Troubleshooting flowchart for central heating operational issues.

Domestic Hot Water Troubleshooting Sequence

Troubleshooting flowchart for domestic hot water operational issues.

Fault Finding Solutions A-D

Solutions for specific fault codes A through D.

Fault Finding Solutions E-K

Solutions for specific fault codes E through K.

Benchmark Installation Checklist