Selecting the hydraulic
connection
2-conductor cooling system
■
Wall installation without valve
assembly:
When the fan is switched
off the flow of air from the air
inlet can be ignored without
sacrificing comfort. In this
application case, use of a valve
assembly is not absolutely
essential.
■
Ceiling installation without
valve assembly:
A valve assembly must be
used in this application case
to prevent the flow of cold
air from the air outlet when
the fan is switched off.
■
Wall installation with valve
assembly:
In order to prevent any
flow of cold air and severe
condensate formation,
for
reasons of comfort
a valve assembly can be used
inthis application case.
■
Ceiling installation with valve
assembly:
In order to prevent any flow
of cold air and permanent flow-
generated noise, for reasons
of comfort a valve assembly
is recommended in this
application case.
System components
required
Valve assembly for 2 or
4-conductor systems (accessory)
In 2 or 4-conductor systems, cold
or warm medium is fed through
the heat exchangers into the unit
and cold or warm air can be
discharged. Control is provided
by the 3-way valve assembly.
It consists of the electrically
actuated valve head and the valve
body. If the head is electrically
activated, it actuates the body,
which routes the medium into
the register. If the temperature
is reached, the head is switched
off and the medium is fed past
the heat exchanger through
the bypass . The bypass serves
to ensure the minimum medium
flow rate for the chiller.
Valves for hydronic balancing
The calculated individual pressure
losses in the pipeline network
layout for each individual unit
are adjusted to the entire system
with hydronic balancing valves
to be provided by the customer.
The nominal flow rates for
the medium adjust to the values
needed as a consequence
of the pressure loss.
The time between being fully
open and fully closed can
be approx. three minutes.
NOTE
Connection of the medium
piping
■
The connection of the piping
by the customer is made
on the rear side of the units.
■
For the purpose of servicing,
connections must be equipped
with shut-off valves and
the medium flow rate adjusted
using hydronic balancing
valves.
■
Additional automatic bleed
valves must be provided
in the supply and return flows
at the installation's highest
point.
■
The medium piping must
not exert any structural load
on the unit.
■
The pipe connections must
not impose any thermal
or mechanical stresses
on the unit.
If necessary, cool the piping
or support with the second tool.
2-conductor system
for cooling and heating
■
As the 2-conductor system
must cool and heat equally,
for reasons of convection
during winter operation,
a valve assembly is stipulated
for all installation methods for
this system operation to avoid
undesirable heat emission.
4-conductor system
for cooling and heating
■
As the 4-conductor system
must cool and heat equally, two
valve assemblies are stipulated
for this system operation for
the cooling and heating register.
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