35
1.
Switch OFF the power supply to the system (e.g. at
a separate fuse or a mains isolator).
2.
Remove the front cover. See page 33.
Fig. 28
3.
Note
Reset button
B
is red
D
when locked out.
Use a screwdriver to press the reset button.
The reset button turns white
C
.
4.
Fit the front cover with an earth cable.
5.
Switch ON the power supply.
Note
If the DHW heat pump high limit safety cut-out
locks out several times in a row, replace heat pump
control unit
A
.
Replacing the heat pump control unit
1.
Switch OFF the power supply to the system (e.g. at
a separate fuse or mains isolator).
2.
Remove the front cover. See page 33.
Fig. 29
3.
Disconnect cables
B
from heat pump control unit
A
.
4.
Remove 4 screws and spacer sleeves, then the
remove heat pump control unit.
5.
Fit the new heat pump control unit.
6.
Connect the cables to the heat pump control unit.
7.
Fit the front cover with an earth cable.
8.
Switch ON the power supply.
Draining the DHW cylinder from the DHW side
1.
Shut off the cold water supply.
2.
Open the DHW draw-off points to release pres-
sure.
3.
Drain the DHW cylinder from the drain valve in the
cold water supply.
Maintenance
Maintenance
(cont.)
5788 057 GB
Maintenance
