Changing Components - Potterton Promax System HE Installation And Servicing Instructions

Heat Exchanger
Manifold
Drain Point
Fig. 44
Air Vent
Sealing Washer
Fig. 45
Tube

13.0 Changing Components

13.1 Changing Components
IMPORTANT: When changing components
ensure that both the gas and electrical
supplies to the boiler are isolated before any
work is started.
When the boiler control knob is switched off
the control PCB remains live. Therefore it is
important to isolate the electrical supply.
Hazardous materials are not used in the
construction of Potterton 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).
2. Isolate the water circuit and drain the system
as necessary. There are 3 drain points:
a) Flow Valve
b) Heat Exchanger Manifold
c) Return Valve
NOTE: Do not use the Pressure Relief Valve to
drain the circuit.
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 6.2 and 10.1).
The air vent, flowswitch, thermistor, safety
thermostat and expansion vessel can be
accessed after removal of the outer case.
13.2 Automatic Air Vent (Fig. 45)
1. Drain the boiler.
2. Undo the 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.
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