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Alpha E-Tec 25R - Component Replacement
8.11 PRIMARY HEAT EXCHANGER - Fig. 7.4
Gain access and drain the boiler heating circuit as described in Sections 8.1 and 8.2.
1. Remove the condensate trap assembly as described in Section 8.10.
2. Remove the combustion manifold as described in Section 7.2.
3. Unplug the connection from the flue temperature sensor and remove the sensor as described in Section 8.6.
4. Disconnect the condensate drain pipe by pulling its rubber connector from the heat exchanger.
5. Disconnect the flue sensor wires and remove the lower retaining screw on the bottom of the heat exchanger.
6. Remove the heating flow and return pipe retaining clips from the primary heat exchanger and pull the pipes downwards
from the heat exchanger connections.
7. Lift the heat exchanger upwards and forwards to disconnect it from the bottom bracket and withdraw it from the boiler.
8. Remove and refit the plastic blanking cap on the right side of the heat exchanger.
9. Reassemble in reverse order using the lubricant supplied with the heat exchanger kit.
Note:
Lubricating the seals with soap and water will aid assembly.
10. Refill the system and visually inspect for leaks.
11. Test the boiler, check the ignition and test the combustion as described in Section 6.
8.12 PRIMARY TEMPERATURE SENSORS - Fig. 7.4
Gain access to the boiler as described in Sections 8.1.
1. Unplug the wiring and unclip the sensor from the flow or return pipe as required. Re-assemble in reverse order with a
new sensor onto the conductive paste ensuring good contact between the pipe and sensor.
8.13 COMBUSTION CHAMBER INSULATION
1. Remove the complete burner/fan/air inlet assembly as described in Routine Servicing, Section 7.2.
2. Using a flat screwdriver in the slots of the three spring clips lever each clip out of its retaining groove (see Fig. 7.3) and
carefully lift off the insulation panel. It may be necessary to remove the electrode assembly first as described in Section
8.3.
3. To remove the rear insulation panel, open the four clips and prise out the panel.
4. Fit the new panel(s) and re-assemble in reverse order referring to Routine Servicing, Section 7.5.
5. Test the boiler, check the ignition and test the combustion as described in Section 7.
8.14 ALPHA CONTROLS (if fitted)
Refer to Section 5.11 on the connection options for boiler controls.
8.15 OVERHEAT THERMOSTAT
1. Gain access to the boiler as described in Section 8.1.
2. Unplug the wiring and remove the retaining pin from from the base of the thermostat.
3. Unclip the sensor from the flow pipe.
4. Re-assemble in reverse order using a new overheat thermostat in the same position as the original and refit the
retaining pin.