Keston System s30, Installation And Servicing Instructions

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Installation and Servicing
SECTION 2 - INSTALLATION
INST
ALLA
TION
2.16 REPLACING PRE-FITTED MAINS CABLE
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 2.18 and be
caried out by a qualified person to avoid a hazard.
1. Isolate the mains supply to the boiler.
2. Remove the front panel. Refer to Section 3.2.
3. Swing the control box down into the service position, unclip and swing
back the installer wiring cover to latch into the retaining clips. Refer to
Section 3.8.
4. Unplug the mains connector and release the cable from strain relief.
5. Unscrew the L N & E connections & remove wires from connector.
6. Remove the mains cable by pulling back through the grommet .
7. Route the replacement cable through the grommet and re-fit in
reverse order.
8. Close the installer wiring cover ensuring that it is located correctly and
that the cable is retained into the strain relief as shown.
9. Swing the control box back up into the operating position and re-fit
the front panel ensuring a good seal is made.
NOTE. When making the mains electrical connections to the boiler it
is important that the wires are prepared in such a way that the earth
conductor is longer than the current carrying conductors, such that if the
cord anchorage should slip, the current carrying conductors become taut
before the earthing conductor.
Strain Relief
6
4
FITTING THE KIT
Fitting the sensor
The air sensor should be located on an external wall of the building
to be heated. Fix the sensor to a north/north-east facing wall to avoid
direct radiation from the sun. The air sensor should be located to
avoid any heating effect from the boiler flue.
To fix the air sensor to the wall, unscrew the sensor box plastic cover
and screw/plug the sensor body to the wall.
Wire a twin core 0.5mm
2
cable from the sensor to the boiler through
an RH grommet located on the underside of the control box. Cable
length between sensor and boiler should be no greater than 20m.
Note that this connection is protected extra low voltage. It is not
necessary for the person carrying out the wiring to be approved to
Part P of the Building Regulations.
Avoid running this cable alongside mains voltage cables.
2.17 FITTING THE WEATHER COMPENSATION KIT - SUPPLIED AS STANDARD
This kit provides the facility to apply outside air temperature control to the boiler water
flow temperature which provides energy savings. The outside sensor provided measures
outside air temperature and sends a signal to the boiler, which adjusts the maximum boiler
flow temperature in response. If outside air temperature is greater than the system design
temperature, the boiler flow temperature is reduced providing running cost savings. The boiler
will operate in the condensing mode more frequently increasing savings.
Once the sensor is fitted it is automatically detected.
The sensor operation may be configured by adjustment of the boiler operating parameters, if
necessary.
Outside Air Sensor