IDEAL HP180IND, Installation & Servicing

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Schematic Open Vented Primary System (HP & Slimline)
Schematic Sealed Primary System (HP & Slimline)
Warming/Overflow
Pipe
F & E Cistern
Minimum
distance as
required by
heat pump
manufacturers
instructions
Port A
Pump
Port A
Heat Pump Heat Pump
Indoor
Unit
Indoor
Unit
Pump
• Sealed heating system
A heat pump selected must be suitable for
use in a sealed heating system which may
have working pressure of up to 3.0bar and it
must be fitted with an overheat temperature
cut-out device.
Unvented (i.e. sealed primary circuits may
be filled or replenished by means of a
temporary connection between the circuit
and a water supply pipe provided a WRC
‘Listed’ double check valve and filling loop
or some other no less effective backflow
prevention device is permanently connected
at the inlet to the circuit and the temporary
connection is removed after use.
Alternatively, a CA device can be used which
will allow the system to be permanently
connected to the cold mains supply. The
primary system can then be topped up,
when required, in the same way as an open
vented system fitted with an F&E cistern.
• Open vented heating system
It is essential that the primary circuit
between the heat pump and the Ideal HP
is pumped and that the cold feed and open
vent connections are positioned to prevent
pump over into the feed and expansion
cistern and to ensure that the open vent is
correctly sized. A typical arrangement of the
open vented system is shown in diagram.
INSTALLATION
INSTALLATION
Heating And Primary Systems
Although the heat pump and the primary heating system should be sized and installed
in accordance with BS EN 12828:2003, BS EN 12831:2003 & BS EN 14336:2004 the
following should also be taken into account during the design and installation phase.
The heat pumps normally operate at lower flow temperatures; typically 45 – 55°C
compared with 75 – 80°C for the boilers. Therefore if traditional radiators are used
then, these should be oversized in accordance with the heat pump manufacturers
recommendations.
For optimum efficiency (i.e. COP of a heat pump), low temperature under floor heating
system should be considered.
The heat pumps normally operate at lower temperature difference between flow and
return compared with the traditional boilers and therefore when sizing the pipework
heat pump manufacturers recommendations should be taken into account.
Safety
Ideal HP is fitted with a combined temperature and pressure relief valve to cope with
any increase in temperature and pressure in the cylinder above the design limits,
when used with heat sources up to 45kW total output. This is the maximum heat
input to the cylinder allowed by section G3 of the ‘Approved Document G’ of the
Building Regulations.
The heat supply to the cylinder and hence the temperature of the stored water should
be controlled as outlined below: -
• Heat supply from the primary heat source i.e. heat
The 3-port spring return motorised valve supplied should be fitted adjacent to the
unit and controlled by the cylinder thermostat (combined control and overheat
thermostat) supplied with the unit. The motorised valve and the thermostat must be
wired so that the motorised valve switches off when either the control thermostat
contact breaks when the set temperature is reached or the overheat thermostat
contacts break when an overheat condition develops. The operation of the heat
source should be controlled via the auxiliary switch of the motorised valve.
It is important to follow the wiring diagrams in the wiring section of these
instructions.