89 CH EXPANSION VESSEL REPLACEMENT
1. Refer to Frame 53 & 54.
2. Drain the boiler. Refer to Frame 85.
3. Undo the union nut on the vessel water
connection pipe.
4. Remove the screw and remove the securing
clamp.
5. Remove the expansion vessel.
6. Fit the new expansion vessel.
7. Re-assemble in reverse order.
9. Check operation of the boiler. Refer to Frame
49.
Note.
If preferred, and for convenience, a new expansion
vessel may be installed elsewhere in the heating
system providing it ensures equivalent system
protection.
90 DHW EXPANSION VESSEL REPLACEMENT
1. Refer to Frame 53 & 54 .
2. Close the DHW inlet valve on the piping frame.
3. Release the DHW pressure by opening a hot tap.
4. Undo the union nut on the DHW expansion vessel.
5. Slacken backnut and remove the expansion vessel
from its bracket.
6. Fit the new expansion vessel.
7. Re-assemble in reverse order.
istor system store -
Installation and Servicing
SERVICING
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