Glow-worm Betacom2 - Manual (Page 43)

0020145065_01 - 09/12 - Glow-worm
18.4.2 Automatic air vent
• Drain the boiler heating circuit as described in the appropriate
chapter "Draining".
• Remove the retaining clip (19). Remove the automatic air vent
(18).
• Fit the new automatic air vent and ‘O’ ring ensuring the vent
cap is left loose.
• Refill, vent and pressurise the boiler.
18.4.3 Low water pressure sensor
• Drain the boiler heating circuit as described in the appropriate
chapter "Draining".
• Disconnect the electrical lead (4).
• Remove the retaining clip (6), remove the low water pressure
sensor (5).
• Fit the new low water pressure sensor.
• Refill vent and pressurise the boiler.
18.4.4 Safety discharge valve
• Drain the boiler heating circuit as described in the appropriate
chapter "Draining".
• Remove the low water pressure sensor as described in the
previous section.
• Undo the safety discharge valve union and remove the pipe.
• Disconnect the Central Heating isolation valve.
• Remove the securing clips and withdraw the safety discharge
valve plastic housing (29).
• Remove the safety discharge valve.
• Fit new ‘O’ ring. Refill, vent and pressurise the boiler.
18.4.5 Flow sensor and impeller
• Remove the the electrical connection (12).
• Unclip the flow sensor (13).
• Unscrew the impeller housing (28) and remove the impeller.
18.4.6 bypass
• Drain the boiler heating circuit as described in the appropriate
chapter "Draining".
• Remove the bypass valve retaining nut (26) to remove the
bypass from its housing (25).
• After replacing the bypass, refill, vent and pressurise the
boiler.
18.4.7 3 way valve motor and diverter valve
• Drain the boiler heating circuit as described in the appropriate
chapter "Draining".
• Disconnect the electrical plug (2).
• Remove the retaining clip (3).
• Remove the three way valve motor (1).
• Remove the diverter valve retaining nut.
• Remove the diverter valve.
• Fit new three way valve motor and diverter valve assembly.
• Refill, vent and pressurise the boiler.
18.4.8 Plate-to-plate heat exchanger
• Drain the boiler heating and domestic hot water circuits as
described in the appropriate chapter "Draining".
• Remove the two securing screws (23).
• Remove the plate-to-plate heat exchanger (17).
• When replacing the plate-to-plate heat exchanger, ensure that
the four rubber sealing washers are fitted into the hydroblock.
NOTE: The plate-to-plate heat exchanger only fits one way.
• Refill, vent and pressurise the boiler.
MAINTENANCE
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