2
B029
Page No.
1. SERVICING INSTRUCTIONS
1.1 Replacement of Parts
3
1.2 To Gain General Access
- Removing the Front Panel
3
- Removing the Side Panels
4
- To Lower the Control Panel
4
1.3 Access to the Combustion Chamber
- Removing the Sealed Combustion Chamber
5
- Removing the Burner and Injectors
5
- Removing the Electrodes
6
- Removing the Main Heat Exchanger
7
- Removing the Air Pressure Switch
7
- Removing the Venturi Device
8
- Removing the Fan
8
1.4 Servicing and Removal of the Gas Valve
- Setting Gas Pressure
9
- Removing the Spark Ignitor
11
- Removing the Gas Valve
12
1.5 Access to the Hydraulic Circuit
- Removing the D.H.W. (Secondary) Exchanger
12
- Removing the Safety Valve
13
- Removing the Automatic Air Vent
13
- Removing the Main Flow Circuit Switch
13
- Removing the Pump
14
- Removing the Pressure Gauge
14
- Removing the Expansion Vessel
15
- Removing the Overheat Thermostat
15
- Removing the Heating Temperature Sensor (N.T.C.)
15
1.6 Access to the Control System
- Checking the Fuses
16
- Removing the Time Clock
16
- Removing the P.C.B.s
17
2. FAULT FINDING
2.1 Fault Finding Guide (Flow-chart)
18
2.2 Fault Finding Using the Total Check System
23
3. ELECTRICAL DIAGRAMS
3.1 Electrical Connection
24
3.2 Functional Flow Connection
25
4. SHORT SPARE PARTS LIST
26
TABLE OF CONTENTS