gledhill Stainless Lite HP SOL Indirect 180-400 litres Design, Installation & Servicing Instructions page 18

INSTALLATION
Schematic Open Vented Primary System (HP SOL)
Warming/Overflow
Pipe
F & E Cistern
Minimum
distance as
required by
heat pump
manufacturers
instructions
Pump
150mm max.
Heat Pump
Schematic Sealed Primary System (HP SOL)
Expansion
Vessel
Safety Valve
Gauge
Heat Pump
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 fl ow 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 effi ciency (i.e. COP of a heat pump), low temperature under fl oor heating
system should be considered.
The heat pumps normally operate at lower temperature diff erence between fl ow and
return compared with the traditional boilers and therefore when sizing the pipework
heat pump manufacturers recommendations should be taken into account.
Safety
Stainless Lite HP is fi tted 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.
INSTALLATION
Motorised Valve
(Energy cut-out)
Motorised Valve
Motorised Valve
(Energy cut-out)
Motorised Valve
Pump
Schematic Open Vented Primary System (HP & Slimline)
Warming/Overflow
Pipe
F & E Cistern
Minimum
distance as
required by
heat pump
manufacturers
instructions
Pump
150mm max.
Heat Pump
Schematic Sealed Primary System (HP & Slimline)
Expansion
Vessel
Safety Valve
Heat Pump
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 2-port spring return motorised valve
supplied should be fi tted 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.
Page 18
Motorised Valve
(Energy cut-out)
Motorised Valve
Motorised Valve
(Energy cut-out)
Gauge
Motorised Valve
Pump