Quick Start Manual

13.0 Changing Components
38
© Baxi Heating UK Limited 2005
13.1 Changing Components
IMPORTANT: When servicing ensure that both the gas
and electrical supplies to the boiler are isolated before
any work is started.
“The boiler cannot be switched off at the boiler,
therefore it is important to isolate the electrical supply
at the mains fuse.”
Hazardous materials are not used in the construction of
Baxi products, however reasonable care during service is
recommended.
When replacing the combustion box door after changing
components, it is essential that the retaining screws are
tightened fully.
1. Remove the outer case and lower door panel (see
“Fitting the Outercase” Section 11.0).
WARNING: The PCB Control and Fan
Assembly is 325 Vdc. Isolate at supply before
access.
2. Isolate the water circuit and drain the system as
necessary. There are 4 drain points:
a) Flow Valve
b) Heat Exchanger Manifold (Fig. 45)
c) Return Valve
d) Cold Water Inlet
NOTE: When reassembling always fit new ‘O’ rings,
ensuring their correct location on the spigot. Green
“O” rings are used for gas joints and Black “O”
rings for water joints. Use Greasil 4000 (Approved
Silicone Grease).
3. After changing a component re-commission the boiler
where appropriate and check the inhibitor concentration
(see Section 6.1 and 10.1).
The air vents, flowswitch, thermistor, safety
thermostat and expansion vessel can be accessed after
removal of the outer case.
13.2 Manual and Automatic Air Vent (Fig. 46)
1. Drain the boiler.
2. Undo the manual air vent from the flow pipe or the
automatic air vent from the return pipe and retain the
sealing washer.
3. Remove the air vent.
4. Fit the new air vent and reassemble in reverse order.
Fig. 45
Heat Exchanger
Manifold
Drain Point
Tube
Fig. 46
Automatic Air
Vent
Sealing Washer
Manual Air Vent