Medium Connections Multi-DENCO
72 FläktGroup DC-2013-0101-GB • Subject to modifications • R5-08/2020
6.3 Refrigerant pipework testing procedures
On completion of the refrigeration pipework the equipment must be pressure tested
with dry nitrogen, at a pressure relevant to the refrigerant used. This should be com-
pleted by a competent person holding the relevant refrigerant handling qualification.
Leak testing A thorough leak test must be performed to ensure that the system is 'leak tight'. It must
be carried out at pressure, using oxygen-free nitrogen. This can be carried out at rela-
tively low pressures (see below) in accordance with safe methods of working and good
refrigeration practice
Certification On all new installations once the system is found to be leak free, a label stating date
and time and final pressure reading is to be attached to the pipework inside the unit.
A pressure test certificate must be signed, witnessed and passed to the commissioning
engineer.
Pressure Relief Valves could be fitted:
– On W-Version units on the liquid receivers in the WaterCool Module
– On P-Version units on the shell and tube condenser in the WaterCool Module
– On outdoor units (condensers) that are fitted with liquid receivers or winter kits
(A-Version)
NOTE!
The procedures below are according to EN 378 and are the minimum standards
expected during leak, pressure and strength testing. Always refer to your country/
region specific legislation.
NOTE!
The use of 'tracers' or 'dyes' are not permitted on Multi-DENCO units under any cir-
cumstances.
NOTE!
Depending upon your commercial agreement, you may be required to perform the
vacuuming and oil and refrigerant pre-charging of the system, before the commis-
sioning engineer's arrival.
For details of this 'Pre-Commissioning Procedure' please see chapter 8 'Commis-
sioning' and in particular chapter 8.2.6 'Initial charge for refrigerant circuits'.
Important safety information is listed at the start of chapter 8, therefore read the
whole chapter IN FULL before commencing any work.
Pressure Relief Valves (PRV) are essential safety devices to prevent the risk of
excess pressure within the direct expansion circuit / liquid receiver causing an
explosion or rupture.
However, to successfully conduct pipework pressure testing, it is be required to iso-
late the PRV using the in-line Shut Off Valve (SOV).
During pressure testing:
• Isolate the PRV by setting the inline SOV to the CLOSED position
• Conduct the pressure test as per the instructions in the following chapters
• Ensure the SOV is set to the OPEN position after testing
To Next Page
Loading...
