Alpha 28X - Pressure Gauge; Primary Temperature Sensor; Automatic Air Vent

34
Alpha InTec C and X - Component Replacement
6. Unplug the fan and remove it from the boiler.
7. Remove the heating flow and return pipe-retaining clips from the primary heat exchanger and pull the pipes downwards
from the heat exchanger connections.
8. Slide the heat exchanger downwards and forwards to disconnect from the flue connection and withdraw it from the
boiler.
9. Re-assemble in reverse order, ensuring that new seals are used.
Lubricating the seals with soap and water will aid assembly.
10. Refill, pressurise the system and vent the air from the heat exchanger using the manual air vent. (Refer to
Commissioning, Section 5.1).
7.20 PRESSURE GAUGE - Fig. 34
1. Gain access behind the casing and drain the boiler heating circuit as described in Sections 7.1 and 7.2.
2. Withdraw the retaining clip securing the pressure gauge sensor (just to the left of the automatic air vent) and withdraw
the sensor.
3. Remove the main cable grommet in the bottom panel and remove the sensor tube.
4. Depress the two lugs on the pressure gauge and push it out of the control panel.
5. Fit the new gauge using a new 'O' ring on the connection if necessary.
6. Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
7.21 PRIMARY TEMPERATURE SENSOR - Fig. 30
1. Gain access as described in Section 7.1 and drain the heating circuit described in Section 7.2.
2. Disconnect the wiring and unscrew the sensor. Re-assemble in reverse order with a new sensor and sealing washer.
3. Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
7.22 AUTOMATIC AIR VENT - Fig. 34
1. Gain access behind the front casing and drain the boiler heating circuit as described in Sections 7.1 and 7.2.
2. Turn the automatic air vent anticlockwise and lift it out
3. Insert the new air vent using a new washer and turn it clockwise to lock it in position.
4. Refill and pressurise the system. (Refer to Commissioning, Section 5.1).
Fig. 34
Primary pressure switch
Automatic air vent
Pump
Pressure relief valve
Pressure gauge
Drain point
Pressure gauge sensor position