Glow-worm Ultimate c - Manual (Page 44)

0020167175_01 - 02/13 - 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.
•
Refi ll, 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.
•
Refi ll 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. Refi ll, vent and pressurise the boiler.
18.4.5 Flow sensor and impeller
•
Remove the the electrical connection (12).
•
Unclip the fl ow 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, refi ll, 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.
•
Refi ll, 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 fi tted into the hydroblock.
NOTE: The plate-to-plate heat exchanger only fi ts one way.
•
Refi ll, vent and pressurise the boiler.
MAINTENANCE
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