Potterton Performa 24 Installation & Servicing Instructions Manual page 35

Microswitch &
Bracket
Diaphragm
Heating
Flow Pipe
Fig. 84
Diverter Manifold
Cartridge
Body
Filter Gauze
Fig. 85
Flow
Regulator
Venturi
Central Heating
Pressure Differential
Valve
Sensing Pipe
Spring Clip
Pressure Gauge
Capillary
Inlet / Return Manifold
12.0 Changing Components
12.21 Diverter Valve Assembly (Cont)
Pressure Differential Valve (Fig. 84)
1. Remove the pressure differential valve as
described above.
By-pass
2. From the brass diverter manifold undo the nut
Pipe
on the heating flow pipe. Remove the screw
securing the diverter manifold to the appliance
lower bracket.
3. Disconnect the pressure gauge capillary from
the diverter manifold and remove the two wires
from the microswitch.
4. Prise off the spring clip securing the by-pass
pipe to the diverter manifold and disconnect the
sensing pipe.
5. Ease the diverter manifold out of the plate
heat exchanger manifold. Remove the assembly
from the appliance.
6. Undo the screw securing the microswitch
bracket to the valve body. The sensor may now
be dismantled to examine the diaphragm.
7. To examine the diaphragm hold the assembly
securely and carefully remove the four screws.
The diaphragm spring will force the two halves
of the valve apart.
8. Carefully examine the diaphragm and replace
it if there is any damage.
9. Reassemble in reverse order.
CH Pressure Microswitch
(Fig. 84)
1. Remove the two wires from the pressure
microswitch.
2. Undo the screw securing the microswitch
bracket to the valve body.
3. Reassemble in reverse order.
12.22 Flow Regulator (Figs. 85 & 86)
1. Undo the filter cartridge from the inlet/return
manifold.
2. Unscrew the venturi and remove the flow
Fig. 86 regulator.
3. Check the cleanliness of the filter gauze,
rinsing thoroughly in clean water as necessary.
Fit the new flow regulator and reassemble in
reverse order.
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