Alpha CD24C Installation And Servicing Instructions page 27

8.17 PRIMARY HEAT EXCHANGER - See Fig. 32
1. Gain access behind the room sealed chamber panel as described
in Section 8.1 and drain the boiler heating circuit as described in
Sections 8.1 and 8.2.
2. Disconnect the gas inlet union from the combustion chamber front.
3. Remove the two screws and six nuts and washers securing the
combustion chamber front burner assembly and remove.
4. Remove the overheat thermostat (Section 8.9), flue thermostat
(Section 8.10) and the primary temperature sensor (Section 8.20).
5. Disconnect the condensate drain union.
6. Remove the two clips from the heat exchanger flow and return
pipes and disconnect the unions at the pump and diverter valve (if
applicable).
7. Remove the four screws securing the heat exchanger retaining
brackets.
8. Lift up the heat exchanger off the pipes and remove it by carefully
withdrawing it out of the boiler.
9. Re-assemble in reverse order, ensuring that new seals are used.
Lubricating the seals with the grease supplied will aid assembly.
10. Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
8.18 COMBUSTION CHAMBER INSULATION
Gain access to the combustion chamber as described in Section 8.1.
Front insulation - see Fig. 27
1. Remove the electrodes from the combustion chamber front as described in Section 8.3.
2. Remove the four screws securing the burner.
3. Carefully remove the insulation.
Back insulation - see Fig. 32
1. Remove the combustion chamber front/burner assembly.
2. Remove the centre screw retaining the insulation.
3. Carefully remove the insulation, suction applied to the centre of the insulation will aid this.
Fit a new panel and re-assemble in reverse order.
Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
8.19 PRESSURE GAUGE - Fig. 33
1. Gain access behind the casing and drain the boiler heating circuit as described in Sections 8.1 and 8.2.
2. Remove the nut securing the pressure gauge sensor and withdraw the sensor.
3. Depress the two lugs on the pressure gauge and push it out of the control panel.
4. Fit the new gauge using a new washer on the manifold connection if necessary.
5. Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
Primary pressure switch
Pressure gauge
Fig. 33
Alpha CD24C/32C - Component Replacement
Fig. 32
Automatic air vent
Pump
Pressure relief valve
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