Heatrae Sadia ELECTROMAX Installation & Servicing Instructions Manual page 41

9.3.10 Removing the Electric Boiler Main
Control PCB
(a) Remove cover from over the electric boiler
control pcb (see diagram 43, page 39).
(b) Disconnect cables from the terminal
blocks.
(c) Unplug ribbon cable connector CONN 2.
(d) Unplug the thermistor connector from
CONN 4. Unplug the over-temperature
cut-out connector from CONN 3.
(e) Remove the pcb securing screws (numbered
1 to 4 on diagram 46, page 41).
(f) Carefully remove the pcb assembly from
the boiler pipework. This may be stiff
and gentle prising from the top may be
required.
(g) Disconnect the cables from the electric
boiler element connections.
(h) Replacement is a reversal of the above
procedure. Ensure the correct element
connections are made. The element
terminals are colour coded to correspond
with the same colour connecting wires
from the pcb, ensure they are connected
to the correct elements. Ensure heat sink
compound is applied to the underside
of the heat sink. Refit the pcb tightening
the fixing screws in the order indicated on
diagram 46, page 41. Ensure all electrical
connections are correctly made (refer to
wiring diagram 14, page 21) and tightened
fully. Loose terminations can overheat and
cause a fire hazard.
9.3.11 Removing the 3 amp Panel mounted
fuses (see diagram 47, page 41)
(a) Remove fuseholder end cap from control
assembly using screwdriver.
(b) Replace 3 amp fuse.
(c) Replace fuseholder end cap.
Terminal Blocks
1
3
Diagram 46 Electric Boiler Control PCB
Fuse
Fuse
Holder
Screw
Driver
Diagram 47 Replacement 3 Amp Fuse
Installation & Servicing Instructions
CONN 5
FS 1 T 2A 240V
2
4
CONN 2
41