Technical data

23
8.16 PRESSURE GAUGE - Fig. 22
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).
Alpha SY9-24 - Component Replacement
Fig. 22
8.17 PRIMARY TEMPERATURE SENSOR - Fig. 19
1. Gain access to the combustion chamber as described in section 8.1 and drain the heating circuit as described in section
8.2.
2. The sensor is positioned on the right hand side of the heat exchanger, see Fig. 19. Disconnect the wiring and unscrew the
sensor. Re-assemble in reverse order with a new sensor and sealing washer.
8.18 AUTOMATIC AIR VENT - Fig. 23
1. Gain access behind the casing and drain the boiler heating circuit as described in sections 8.1 and 8.2.
2. Unscrew the automatic air vent from the pump outlet. Fit a new one using a new 'O' ring.
3. Refill and pressurise the system. (Refer to Commissioning, section 5.1).
8.19 PUMP - Refer to Fig. 23
Gain access behind the casing and drain the boiler heating circuit as described in sections 8.1 and 8.2.
Pump head
1. Remove the four socket head screws securing the pump head to the body. Withdraw the head, remove the wiring cover
and disconnect the wiring.
2. Connect the wiring to the new head as follows:-
Brown to L, Blue to N, Green/yellow to
.
Ensure the pump is set to maximum (3) and re-assemble in reverse order.
3. Refill and pressurise the system. (Refer to Commissioning, section 5.1).
Complete pump
1. Remove the pump head as described above.
2. Unscrew the automatic air vent from the pump outlet.
3. Disconnect the pump unions and withdraw the pump body.
4. Connect the wiring as described above, ensure that pump is set to maximum and re-assemble using new sealing washers.
5. Refill and pressurise the system. (Refer to Commissioning, section 5.1).
8.20 PRIMARY PRESSURE SWITCH - Fig. 23
1. Gain access behind the casing and drain the boiler heating circuit as described in sections 8.1 and 8.2.
2. Disconnect the wiring from the pressure switch.
3. Unscrew the switch from the primary flow pipe.
4. Using the new washer supplied, re-assemble in reverse order.
When connecting the wiring to the new switch the polarity of the wires is not important.