50
Installation and Servicing
SECTION 3 - SERVICING
3.23 SAFETY RELIEF VALVE REPLACEMENT
1. Refer to Section 3.8.
2. Drain the boiler. Refer to Section 3.21.
3. Remove the clip on return thermistor. Refer to Section 3.12.
4. Pull out and remove the clip (positioned behind the safety
valve) retaining the safety valve.
5. Undo the safety valve pipe compression tting positioned
outside the boiler casing.
6. Lift out the safety valve/pipe assembly.
7. Remove the safety valve pipe and transfer to the new safety
valve.
8. Reassemble in reverse order ensuring the retaining clip is
correctly tted, the pipe compression tting retightened and
return thermistor is re-clipped.
9. Rell the boiler. Check that the boiler operates in both DHW
& CH modes.
3.24 PUMP AUTOMATIC AIR VENT REPLACEMENT
1. Refer to Section 3.8.
2. Drain the boiler. Refer to Section 3.21.
3. Remove the expansion vessel. Refer to Section 3.32.
4. Firstly, increase access area by disconnecting the 22mm pipe connection at
top of pump manifold and bottom of heat exchanger and remove pipe. Refer
to Section 3.26.
5. The automatic air vent head is retained in the pump body with a bayonet
connection. The air vent head and oat assembly is removed by turning the
head anti-clockwise (viewed from above) and pulling upwards.
6. Reassemble in reverse order. Ensure the air vent head ‘o’ ring seal is tted.
7. Ensure the air vent cap is loose.
8. Rell the boiler. Refer to Section 2.16. Check for leaks around the new air vent
joint.
9. Check that the boiler operates in both DHW & CH modes.
5
3 4
Dust Cap
3.25 DHW FILTER & DHW FLOW REGULATOR CLEANING/REPLACEMENT
1. Refer to Section 3.8.
2. Drain the DHW system. Refer to Section
3.21.
3. Turn the housing anti clockwise and pull
forward to remove the cartridge.
4. Using a pair of pliers, pull out the plastic
lter/ow regulator.
5. Clean or replace lter as necessary.
6. Reassemble in reverse order.
7. Rell the boiler.
8. Check that the boiler operates in both
DHW & CH modes.
3
4
SERVICING