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Installation and Servicing
Section 2 - Installation
INST
ALLA
TION
2.21 REPLACING PRE-FITTED MAINS CABLE
Strain Relief
If it is necessary to use an alternative mains cable to the one
pre-fitted then use the following guide.
Replacement wiring should comply with notes in Section
2.19
and be caried out by a qualified person.
1.
Isolate the mains supply to the boiler.
2.
Remove the front panel.
3.
Swing the control box down into the service position,
unclip and swing back the installer wiring cover to latch
into the retaining clips.
4.
Unscrew the L N & E connections & remove wires from
connector.
5.
Remove the mains cable by pulling back through the
grommet .
6.
Route the replacement through the grommet and re-fit in
reverse order.
7.
Close the installer wiring cover ensuring that it is located
correctly and that the cable is retained into the strain
relief as shown.
8.
Swing the control box back up into the operating position
and re-fit the front panel ensuring a good seal is made.
The earth connection should be longer than the current
carrying connections. If the cord anchorage slips, the current
carrying wires become taut before the earth.
Wiring External to the Boiler
The fuse rating should be 3 A.
Wiring external to the boiler MUST be in accordance
with the current I.E.E. (BS.7671) Wiring Regulations
and any local regulations.
Frost Protection
If parts of the pipework run outside the house or if
the boiler will be left off for more than a day or so
then a frost thermostat should be wired into the
system.
The frost thermostat should be sited in a cold place
but where it can sense heat from the system.
If the boiler is installed in a garage it may be
necessary to fit a pipe thermostat, preferably on the
return pipework.
EXAMPLE - Connection to Honeywell Evohome
2.22 EXTERNAL ELECTRICAL CONTROLS