IDEAL HP180IND, Installation & Servicing

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Temperature/pressure relief valve
This safety device is also pre-set at the factory and relieves before the temperature
reaches 100°C. It is also a Pressure Relief Valve, and is pre-set to 6 bar.
Immersion Heater
The immersion heaters fitted to our units are 3kW 240V ~AC. Check that the mains
supply conforms to this, and all external wiring conforms to the most recent
revision of the IEE wiring regulations. An Incoloy element is used on this product for
standard domestic use and water conditions, use our Titanium elements in all other
circumstances, part number SH002.
The immersion heater is fitted into the hot water cylinder using an O-ring. After the
unit is filled with water check for leaks to determine if the O-ring has sealed and
tighten carefully using the appropriate tool. To prevent damage to the O ring do not
use excessive force to tighten the immersion heater.
The immersion heater is supplied with a thermostat which has been tested
for operation in the cylinder and complies with the European directives for
Electromagnetic compatibility and radio interference. It is Rated at 20 Amp 250V ~AC.
The immersion thermostat has two terminals L and N. These should be connected as
shown in the diagram. It has been our experience that crimp terminals make better
connections. The immersion heater must be fully earthed (earth post) and connected
via a double pole isolator switch.
Danger of electrocution: before making any adjustments to the thermostat isolate
the immersion heater from the mains electricity supply at the fuse spur unit.
INSTALLATION
INSTALLATION
The immersion heater thermostats incorporate
a manual reset safety/overheat cut out
thermostat. Should this operate, investigate
the cause before pressing the red reset button
labelled safety. If there is no apparent fault
adjust the control setting down slightly to
prevent nuisance tripping.
If another heat source is used to heat the
cylinder and this is allowed to raise the water
temperature excessively then the overheat
thermostat will trip.
All Ideal HP models are fitted with a 3kW
immersion heater so that the store temperature
can be raised above that which the heat pump
provides, to boost the hot water performance
if necessary and to protect against legionella
eg. once a day or once a week.
The operation of the boost immersion heater can
also be controlled by means of an independent
time switch as shown schematically below. The
‘ON’ time settings on the immersion heater
should be between 30 - 60 minutes later than
the ‘ON’ times set for the hot water programmer
channel.
For example if the hot water is programmed to
come on between 0600 - 0900 and 1700 - 2200
then the immersion heater setting should be
0640 - 0900 and 1740 - 2200. This will give hot
water heating by heat pump a priority.
Control/overheat Thermostat
Care must be taken to ensure that the probes
are fully inserted into the pockets provided.
Typical schematic wiring diagram for the boost immersion heater
using immersion programmable immersion heater timer.
Immersion Heater Wiring
Assembly and fitment
for earth cable to stud
Nut
Cup washer
Earth cable
Plain washer
Spring washer
Nut
Thermostat Type WTS fitted in the immersions, and are supplied set in position 4.5 at 61°C ± 3°C.