Diverter Valve Motor; Expansion Vessel; Gas Valve - Potterton 36 Installation And Service Manual

9 Maintenance
Fig.62 Remove diverter valve
Fig.63 Remove expansion vessel
Tab.23 Characteristics of combustion
Potterton Assure Combi
CO
2
Diameter of coaxial discharge pipes
60
9.3.10

Diverter valve motor

1. Disconnect the multi-pin plug from the diverter valve motor.
2. Hold the motor in place against the spring pressure of the valve as­
sembly, remove the securing clip.
3. Remove the motor.
4. When fitting the new motor it will be necessary to hold the unit firmly
while depressing the valve assembly spring to refit the securing clip.
5. Reconnect the multi-pin plug.
PN-0000311
9.3.11

Expansion vessel

Warning
Take precautions to protect other components from water damage
when removing the expansion vessel.
1. Close the flow and return isolation taps and drain the boiler primary
circuit.
2. Relieve the pressure from the expansion vessel.
3. Remove the silencer.
4. Prise off the securing clips and disconnect the braided hose from the
vessel and hydraulic inlet assembly, taking care as water may still
be in the vessel.
5. Ensure that the braided hose is free of restriction, as a boiler with a
blocked hose will exhibit symptoms similar to one with a failed ves­
sel.
Important
Where the hose is found to be blocked, it must be cleared or re­
placed and the vessel recharged to 1 bar.
PN-0000378
6. If the hose is clear support the vessel, undo the locknut and ma­
noeuvre the vessel out of the boiler.
7. Replace the expansion vessel with the new one and reassemble in
reverse order and recharge to 1 bar.
9.3.12

Gas valve

% (maximum) 9.0 + 0.3 – 0.2
% (minimum)
mm
25 30
9.0 + 0.3 – 0.2
8.5 + 0.1 – 0.4 8.5 + 0.1 – 0.4
60/100 & 80/125 60/100 & 80/125
36
9.0 + 0.3 – 0.2
8.5 + 0.1 – 0.4
60/100 & 80/125