Flushing/Descaling The Heat Exchangers - andrews MAXXflo EVO CWH 90/302 Installation And Maintenance Manual

6.3 FLuSHING/DESCALING THE HEAT EXCHANGERS

The following instructions only apply when the optional pressure sensor and
isolation pipe work is fitted
• Start by removing the B8 flue sensor connection (see 6.2.2) from the heat exchanger to be flushed and
wait two minutes for the pump to stop rotating before turning off the heat engine isolation valves.
• Close both water isolation valves and use both of the drain points to drain down water until no further
release of water occurs.
• Connect flushing apparatus to the drain / flushing points
• For best results, reverse the flow of the flushing apparatus
Isolation Valve
• When the operation is completed, thoroughly flush the system to a drain with clean water.
• Retighten the drain / flushing points and open the isolation valves
• Replace the B8 flue sensor connector.
• Operate the pump by pulling the electrical connector off the heat exchanger front flow sensor B2 (see
6.2.14)
• When all sound of air has stopped, reconnect B2 sensor and press the reset for 1 second
Maintenance
Isolation Valve
69
Drain / flushing
point
Drain / flushing
point
MAXXflo EVO