Row
-DENCO
Installation
FläktGroup DC-2014-0106-GB 2019-02/R3 • Subject to modifications
45
8.4.5 Leak testing
•
Connect the manometer to the service connections of the respective refrigeration
circuit on the suction and pressure side.
•
Before leak testing, examine the pressure values on the high and low-pressure
manometer
•
Indicated pressure must be within the overpressure range.
•
In this case, open the liquid shut-off valve and the suction gas shut-off valve to test
for leakage.
•
If no overpressure is measured in the refrigeration circuit of the device, it should be
assumed that the refrigeration circuit in the unit possibly has a leak.
•
If this is the case, close the liquid shut-off valve and the suction gas shut-off valve to
test for leakage.
•
At first, test the refrigeration circuit in the unit on seal effectiveness and possibly
remedy leaks
•
Thereafter, open the shut-off valves in the liquid and suction line and examine the
remaining refrigeration circuit on seal effectiveness.
The system must be depressurized with dry nitrogen to test for leakage as long as the
pipework is accessible and not yet insulated.
For successful testing, test pressure must be as high as possible, but not exceeding
the maximum allowed operating pressure.Introduce nitrogen for depressurizing using
a pressure-reducing valve on the cylinder valve of the unit. The control gauge on the
pressure-reducing valve must be set to the maximum test pressure of the system.
•
Increase pressure in the system in steps, first to 0.1 MPa (1 bar) overpressure and
then to around 0.5 MPa (5 bar) overpressure.
•
All pipe connections must be leak tested using foaming Leak Detection Spray.
•
If no leaks are detected at 0.5 MPa (5 bar) overpressure, pressure is increased to
the maximum allowed test pressure.
•
Perform the pressure test using the maximum allowed test pressure for at least two
hours.
•
Subsequently, overpressure in the system can be reduced.
8.5
Water connections (DRC)
The following are recommended for all water connections:
– flexible connections (available from the options in the price list) to avoid transmitting
vibrations and allow small movements of the
Row
-DENCO
– joints in three pieces, near the fittings, to simplify removal of the unit
– on-off valves to disconnect the unit from the water circuit: where possible use ball
valves with full opening to minimise pressure drop
Notice!
Important: the flexible connections available as accessory are PN10.