40
Installation and Servicing
SECTION 3 - SERVICING
1.
Isolate and drain down the HIU.
Refer to Section 3.5.
2.
Remove the front panel. Refer
to Section 3.4.
3.
Remove front insulation section.
Refer to Section 3.12.
4.
Unplug the electrical lead from
the thermistor.
5.
Unscrew the thermistor (to
facilitate removal a 13mm
socket spanner should be used).
6.
Fit the new thermistor.
7.
Reassemble in the reverse
order.
8.
Refill the HIU. Refer to Section
2.5.
9.
Check that the HIU operates in
both DHW & CH modes.
3.17 DOMESTIC HOT WATER THERMISTOR
3.18 CH FLOW & RETURN THERMISTOR
1.
Remove the front panel. Refer to Section 3.4.
2.
Unplug the electrical lead from the thermistor.
3.
Unclip the thermistor from the pipework.
4.
Fit the new thermistor ensuring it is positioned on the brass tab.
5.
Reassemble in the reverse order.
6.
Check that the HIU operates in both DHW & CH modes.
SER
VICING
