16
General
Pipe installation must be carried out in accordance
with current norms and directives. HPAC can only
work up to a return temperature of around 50°C and a
flow temperature from the heat pump of around 60°C.
As the heat pump is not equipped with shut-off valves,
you have to install them yourself outside the heat
pump to facilitate future service.
The fluid in the building's distribution system is the
same as in the soil/rock collector.
Pipe connection, the building's
distribution system
The heat pump is connected to the HPAC and possi-
ble hot water heating.
Pipes connections are made at the bottom and top of
the HPAC. Requisite safety equipment, shut off valves
(fitted as close to the cooling module as possible), and
particle filters (supplied with the heat pump) are to be
fitted so that the HPAC is also protected.
When connecting to a system with thermostats on all
convectors, a relief valve must be fitted, or a number
of the thermostats must be removed to ensure suffi-
cient flow.
Pipe connections
Pipe connection, collector side
The length of the collector hose varies depending on
the rock /ground conditions and on the distribution
system.
When installing the collector hose ensure it rises con-
stantly towards the heat pump to avoid air pockets. If
this is not possible, install high points to vent the air.
The distribution system should be fitted with two pres-
sure expansionvessels and are pressurised to at least
0.5 bar.
All the system's pipes are to be condensation insulated
except the pipes to the hot water heater.
As the temperature of the brine system can fall below
0 °C this must be protected against freezing through
the mixture of propylene glycol (NOTE! Not ethanol).
The mixing ratio should be approximately 25 % propyl-
ene glycol and the remainder water. As a guideline for
the volume calculation, use 1 litre of ready mixed heat
transfer fluid per meter of collector hose, (for 40 x 2.4
PN 6.3 PEM hose).
The installation should be marked with the antifreeze
used.
Shut-off valves should be installed as close to the heat
pump as possible. Fit a particle filter to the incoming
pipe.
In the case of connection to an open groundwater sys-
tem, an intermediate frost-protected circuit must be
provided, because of the risk of dirt and freezing in the
evaporator. This requires an additional heat exchang-
er.
Condensation insulation
Pipes and other cold surfaces must be insulated with
diffusion-proof material to prevent condensation.
Where the cooling demand is high, fan convectors with
drip trays and drain connection are needed.
HPAC 42