tech level liquid indicators High Pressure
CONSTRUCTION
Moisture
indicators are equipped with a sensitive element that changes color from green
to yellow depending on the humidity level present in the refrigeration circuit.
The indicators in this series are manufactured by integrating the sight glass
directly into the hot‑forged brass body EN 12420 – CW617N, creating a compact,
monolithic structure that minimizes joints between components and eliminates
additional potential refrigerant leakage points. To ensure perfect sealing of
the glass in all models, a modified PTFE gasket is used.
The
connection material varies according to the series:
- MI..MP: copper tube EN 12735‑1 – Cu‑DHP R290
- MI..MPI: stainless steel tube AISI 304
INSTALLATION
During
initial start‑up, the sensitive element may appear yellow, either due to
atmospheric moisture absorbed during handling or because of residual moisture
inside the circuit. Once the refrigerant’s moisture content is brought back to
normal levels through the dehydrator filter, the indicator returns to green.
Indicators of the MI..MP and MI..MPI series can be installed in
any required position.
APPLICATION
Indicators
of the MI..MP and MI..MPI series are classified as “Pressure
accessories” according to PED Directive 2014/68/EU, Article 2, paragraph 5.
The entire product range is suitable for use with refrigerant R744 (CO₂),
classified under Article 13, paragraph 1, letter (b) of the same Directive as a
Group 2 fluid — non‑toxic, non‑flammable, and non‑explosive — and listed
as A1 class in Annex E of EN 378‑1.
According
to Directive 2014/68/EU, the hazard classification of the product depends on:
- the type of fluid used (R744),
- intrinsic dimensions (DN),
- maximum design working pressure (PS).
For the MI..MP
and MI..MPI series, internal nominal diameters (DN) range from 9 mm
for the smallest models up to 25 mm for the largest versions. Maximum
operating pressures, as specified in the technical tables, do not exceed 62
bar for the MI..MP series and 70 bar for the MI..MPI series.
In
accordance with Table 7 of Annex II of PED Directive 2014/68/EU, all
products fall within the scope of Article 4.3.
