Automatic Air Vent; Pressure Relief Valve - Potterton Combi 80 Installation & Service Instructions Manual

Replacement of Parts - Page 36
5.26

Automatic Air Vent

1. Remove the white front case, base panel and white left
hand side panel. See 4.1, 4.2 & 4.3 in 'Routine
Maintenance'.
2. Drain the central heating circuit as described on Page
26.
3. Using a spanner to prevent the retaining nut from
rotating unscrew the auto air vent and remove from the
appliance. If there is insufficient space, removal will be
eased if the complete auto air vent and pipe assembly is
disconnected from the heat exchanger and then raised
above the top of the air box. To do this the fan and
fluehood will need to be removed, see 4.4 & 4.5 in
'Routine Maintenance'.
4. Fit new air vent and sealing washer ensuring the air
vent cap is left loose.
Re-assemble in reverse order, ensure that the grommet
is correctly positioned. Re-charge the system as
described in Section 1.8 and check for leaks.
5.27

Pressure Relief Valve

1. Remove the white front case and base panel.
See 4.1 & 4.2 in 'Routine Maintenance'.
2. Drain the central heating circuit as described on Page
26.
3. Undo the outlet tube nut and fully remove the two grub
screws holding the pressure relief valve to the pump
manifold, undo the top compression joint on the
pressure relief valve discharge pipe then remove the
valve.
Note: The outlet of the pressure relief valve is an olive
connection.
4. Fit the new pressure relief valve using a new 'O' ring
seal and soap solution as a lubricant. Re-assemble in
reverse order.
5. Recharge the system as described in Section 1.8 and
check for leaks.
- Fig. 24
- Fig. 25