Baxi Barcelona System Installation And Servicing Instructions page 30

13.0 Changing Components - Page 30
13.3 Flowswitch (Fig. 46)
1. Drain the boiler
(see Section 13.1 paragraph 2 & 3).
2. It may be necessary to remove the expansion vessel (see
Section 13.5).
3. Remove the clip securing the flow pipe to the flowswitch.
4. Remove the two screws securing the flow switch to the
boiler.
5. Disconnect the inline electrical connection.
6. Remove the flowswitch.
7. Fit the new flowswitch and reassemble in reverse order.
8. Recommission the boiler and check the inhibitor
concentration (see Section 6.2 and 10.1).
13.4 Flow Temperature Thermistor and Safety
Thermostat (Fig. 47)
1. The procedure is the same for both the thermistor and the
safety thermostat.
2. Remove the electrical connections from the sensor.
3. Unscrew the sensor from the pipe.
4. Fit the new thermistor or safety thermostat and
reassemble in reverse order.
13.5 Expansion Vessel (Fig. 48)
1. Drain the boiler (see Section 13.1 paragraph 2 & 3).
2. Loosen the securing screw at the base of the expansion
vessel.
3. Whilst supporting the vessel undo the expansion vessel
connection and retain the sealing washer.
4. Remove the expansion vessel.
5. Fit the new expansion vessel and reassemble in reverse
order.
13.6 Re-pressuring Expansion vessel
1. The charge pressure is 1.0 bar.
2. Close the central heating flow and return isolating valves.
3. Drain the boiler
(see Section 13.1 paragraph 2 & 3).
4. The "Schraeder" valve is positioned centrally at the side
of the appliance. Pressurise to 1.0 bar.
5. Open the isolating valves and recharge the system to
between 1.0 bar and 2.5 bar. Vent the system as necessary.