FläktGroup Multi-DENCO, Operation Manual, Page: 52 / 120

Medium Connections Multi -DENCO
52 FläktGroup DC-2013-0101-GB • Subject to modifications • R4-05/2018
6 Medium Connections
6.1 Requirements
– (For refrigeration circuits) Only pipe sizes recommended by FläktGroup are allowed.
Incorrect pipe sizing can cause compressor damage and void the warranty.
– Every part of all circuit(s) (cooling and heating) must be designed and installed to
national and local standards and regulations.
– Piping must be properly sized to meet the design requirements.
– Mechanical connections shall only be carried out by qualified licensed staff or other
individuals with proper professional training and experience in the relevant accident
prevention regulations, as well as other generally recognized safety and occupatio-
nal health codes.
Only copper refrigerant lines meeting EN 12735-1:2010 standards shall be used for
refrigeration pipework installation. R410A is the standard refrigerant used within
Multi -DENCO units, ensure that pipework used is suitable for the higher pressures
used with this refrigerant.
The relevant requirements of the standard, especially apply to:
– Quality of internal surfaces
– Sealed pipe ends
– Pipe labelling
– Testing
– Pressure resistance
Short line lengths Keep the pipe length as short as possible. The greater the distance between the air
handling unit and the outdoor heat rejection unit, the greater the pressure drops in
connected pipes, resulting in reduced energy efficiency of the unit.
Liquid receivers Installing a refrigerant receiver is not mandatory. With long pipe runs and low ambient
temperature operation of the unit it is, however, recommended to install a refrigerant
receiver. If a receiver is not installed, the refrigerant should be selected and charged
with extreme care. When charging the unit with refrigerant at low ambient temperature,
ensure that the system is not overfilled and the unit can be trouble-free operated at high
ambient temperature as well. Consider the manufacturer's instructions on layout of a
refrigerant receiver and installation manual on mounting a receiver.
6.2 Connecting refrigeration pipework
6.2.1 Pipework
All pipework must be installed in accordance with EN 378-4 and with recognised good
refrigeration practices in a tidy manner. Any further local legislation may vary, but must
be observed.
Within the EU, certain systems may be subject to mandatory requirements of the Pres-
sure Equipment Directive 2014/68/EU. To know the classification of your equipment,
refer to the serial plate on each unit.
Details of the maximum lengths of interconnecting pipework are in chapter 5.6.2.
NOTE!
When routing pipework, take due care that air flow is not obstructed as this may
reduce the efficiency of the system.