Draining The Boiler; Siphon Removal; Primary Sensor (Ch Ntc) - Worcester Greenstar 25Si Compact Installation, Commissioning And Servicing Instructions

SERVICE AND SPARES
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Fig. 76 Removing outer case

7.8.2 DRAINING THE BOILER

Many of the tasks in this section require that the boiler be isolated and
drained.
1. Connect a suitable hose firmly to the drain point and run the hose
outside to a suitable point or container.
2. Turn the drain valve a ¼ turn anti-clockwise to open the drain. Turn
the valve firmly clockwise to close.
Fig. 77 Draining the boiler
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7.8.3 SIPHON REMOVAL

1. Disconnect the discharge hose from the wall frame connector.
2. Rotate the siphon body clockwise to release the bayonet connection.
3. Pull the siphon body down and away from the boiler.
3.
Fig. 78 Siphon removal

7.8.4 PRIMARY SENSOR (CH NTC)

▶ Remove the combustion air inlet pipe from the pre-mix unit, rotate
anti-clockwise and pull away from the fan assembly.
▶ Ease the gas pipe to the left.
▶ Disconnect the lead to the sensor.
▶ Remove the sensor by pulling forward.
▶ Replace the sensor onto the flow pipe.
▶ Connect the lead to the sensor.
▶ Re-fit the combustion air inlet pipe to the pre-mix unit.
Fig. 79 Primary sensor
Greenstar Si Compact
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ErP - 6 720 813 278 (2015/07)