Potterton iHE 100/300, Installation And Servicing Instructions

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iHE 28
CHANGING COMPONENTS
NONE OF THE CONTROLS ARE REPAIRABLE IF THEY
ARE NOT WORKING THEY MUST BE REPLACED
In all cases, before work commences turn off the
Mains Electricity and Gas Supply.
The following items can be replaced:
• Pressure Temperature Relief Valves.
• Flow, Return and DHW Flow Sensors
• LLH and Tank Sensor.
• Flue
Sensor.
• The HMI Display.
• Master and Slave PCBs
• Spark
Generator.
• Spark and Sense Electrodes.
• Gas
Valve.
• Fan.
• Venturi.
• Heat
Exchanger.
• Pumps.
• Plate Heat Exchanger.
• Expansion
Vessel.
P
RESSURE
T
EMPERATURE
R
ELIEF
V
ALVE
The removal of this valve will require either the drain-
ing or the valving off of the system that is above tank
level. Once Isolated the connecting pipework can be
removed and the Valve unscrewed from the Tank.
R
ETURN
, F
LOW AND
DHW F
LOW
S
ENSORS
The Flow and Return Sensors are clipped on to the
copper pipework beneath the Heat Exchangers. The
DHW Flow sensor is clipped to the DHW Flow pipe
at the top of the Tank.
•
Pull off the two leads and unclip the sensor
• Replacement is the reverse.
LLH
AND
T
ANK
S
ENSORS
These sensors are fi tted in to pockets at the top of
the LLH and the Tank, they have in-line connectors
within 500 mm from their pockets.
•
Pull the connector apart and withdraw the sen-
sor.
• Replacement is the reverse.
F
LUE
S
ENSOR
This is located at the Flue outlet of the Heat Ex-
changer.
•
They are removed by turning anti-clockwise a
quarter turn and withdrawing.
• Replacement is the reverse.
AVS 37 HMI D
ISPLAY
• Use a small fl at edged screwdriver to release the
HMI from its mounting bracket, by springing off its
four plastic edge clips.
• Remove the cable from the HMI Display.
• Replacement is reverse.
LMS14 PCB 1
TO
3
These are located on Control Panel. It is important that
the correct PCB replacement is used in the right place.
They are named from top to bottom
PCB1, PCB2 and PCB3.
•
Pull off all the connectors on the PCB.
• Release all 7 PCB supports and withdraw the
board.
• Replacement is the reverse.
S
PARK
G
ENERATOR
This is located at the front of the Heat Exchanger on
the Fan Mounting bracket.
•
Pull off the grey connector to the Generator.
• Release the nut holding the Generator to the
bracket, and remove generator.
• Replacement is the reverse.
S
PARK AND
S
ENSE
E
LECTRODES
These are located on the front of the Heat Exchanger.
•
Pull off the electrical connectors.
• Undo the two screws retaining the bracket and
withdraw.
• Replacement is the reverse.
P
LATE
H
EAT
E
XCHANGER
• Remove the lower left hand side cover to gain ac-
cess to the heat exchanger
• Remove the condense pipework from behind the
heat exchanger.
• Remove the two crosshead screws, located either
side of the heat exchanger.
• Drain as much of the primary and secondary sys-
tems water as possible.
• Release all four heat exchanger connections and
slide the heat exchanger toward the rear of the
appliance
• Replacement is the reverse.