Protherm 80E User, Installation And Servicing Instructions - page 25
24
Diagram 23
To replace hot water thermistor
•
Pull off electrical connections from thermistor and unscrew thermistor (b) from left part of hydraulic block, see
diagram 21.
•
Remove gas valve module as described previously.
•
Fit replacement thermistor in reverse order to removal.
Note:
The polarity of the connections is not important.
To replace printed circuit board (PCB)
Important:
Isolate boiler from electrical supply before this operation.
•
Gently squeeze metal clip securing the control panel box, lift it up and hinge down.
•
From behind control panel box, unscrew and remove 4 screws securing PCB cover to panel.
•
Pull off electrical plugs from PCB.
•
Remove 4 screws securing PCB to panel and lift out PCB.
•
Fit replacement PCB in reverse order to removal.
To replace display and control panel board
Important:
Isolate boiler from electrical supply before this
operation.
•
Remove PCB cover as described in
‘To replace PCB’
.
•
Pull off electrical plug of display (A) from PCB, see dia-
gram 23.
•
Remove 4 screws securing PCB to panel and lift out
PCB.
•
Remove 4 screws securing display and control panel bord
to panel and gently lift it out.
•
Fit replacement display and control panel board in reverse
order to removal.
To replace timeclock
•
Remove PCB cover as described in
‘To replace PCB’.
•
Disconnect clock electrical connections from PCB. Unclench plastic clips securing time-
clock to lower front panel and remove timeclock from panel.
•
Fit replacement timeclock in reverse order to removal.
To replace pressure gauge
•
Drain boiler as described in
‘To replace pump’.
•
Unclip pressure gauge clip and pull it out.
•
Disconnect pressure gauge cable.
•
Fit replacement pressure gauge in reverse order to removal.
To replace heat exchanger
•
Drain down heating circuit of boiler only as described previously.
•
Remove sealed and combustion chamber covers and side cases as described
previously.
•
Remove overheating termostats from heat exchanger pipes.
•
Pull off spring clips securing heat exchanger pipes to heat exchanger.
•
Manoeuvre heat exchanger pipes down to disengage from heat exchanger.
•
Gain acces to heat exchanger by removing fan and flue hood.
•
Remove heat exchanger by sliding forward and out of boiler.
•
Fit replacement heat exchanger in reverse order to removal.
•
Open isolating valves on flow and return connections, refill, vent and pressurise boiler. Check for leaks.
Diagram 24