Diverter Valve - Potterton Puma 100 Installation & Service Instructions Manual

Component Replacement - Page 38
6.24

Diverter Valve

(Fig. 33)
The diverter valve is made up in two parts. The wax
capsule head forms one part and provides the motive
power to open the valve. The second part, the valve
consists of the change over mechanism and the valve
seating. It is likely that only replacement of the head will
be necessary, if the complete valve requires
replacement proceed to (ii).
(i) Wax Capsule Head
a. Remove the white front case and base panel.
See 5.1 & 5.2 in 'Routine Maintenance'.
b. Lower the control panel assembly by undoing the
securing screw at the top right hand side of the control
panel.
c. Close the 15mm cold water isolating valve, open the
lowest hot water tap and remove the D.H.W drain screw
in the isolating valve to drain the system.
d. Close the central heating isolating valves, reduce the
system pressure by opening the pressure relief valve
and drain the water from the heating system by
removing the drain plug from the underside of the pump
manifold.
e. Undo the two D.H.W pipe connections to the valve
head. Retain the two pipe seals.
f. Unscrew the two grub screws (2mm hexagon key)
which hold the head to the main body. Pull the head
forwards using a twisting action and carefully remove
the head. Note the position of the loose brass cylinder
on the wax capsule push rod and transfer onto new
head assembly.
g. Fit new wax capsule head, re-assemble in reverse
order. Replace pipe seals is necessary.
(ii) Complete valve replacement
a. Remove the white front case and base panel.
See 5.1 & 5.2 in 'Routine Maintenance'.
b. Lower the control panel assembly by undoing the
securing screw at the top right hand side of the control
panel.
c. Close the 15mm cold water isolating valve, open the
lowest hot water tap and remove the D.H.W drain screw
on the isolating valve to drain the system.
d. Close the central heating isolating valves, reduce the
system pressure by opening the pressure relief valve
and drain the water from the heating system by
removing the drain plug from the underside of the pump
manifold.
e. Undo the two D.H.W pipe connections from the head of
the diverter valve. Retain the pipe seals.
f. Undo the Central heating pipe connections to the
diverter valve body and loosen the two nuts retaining
the C.H. Flow and Return pipe tails.
g. Remove the locknut at the rear of the diverter valve
holding the valve to the front cross brace.
h. Undo connection to the pump manifold and withdraw
the diverter valve from the boiler.
Transfer the water pressure switch and drain cock to
the new valve and re-assemble in reverse order.