The indicators are classified as “Pressure accessories” in the sense of the PED Directive 2014/68/EU, Article 2, paragraph 5 and are subject of Article 4, paragraph 1, letter (c), of the same Directive. All the product range is suitable for use with hydrocarbon refrigerants R290 (Propane), R600 (Butane), R600a (Isobutane), R1270 (propylene) proper to the Group 1, as defined in Article 13, paragraph 1, letter (a), of PED Directive 2014/68/EU and classified as A3 Group of Annex E of standard EN 378-1.
The function of liquid and humidity indicators is to verify the actual situation of flow and the presence of moisture in the system.
The indicators are made by embedding a spyglass directly into the body of hot forged brass EN 12420 – CW617N or in the annular indicator body of brass EN 12164 – CW614N. This forms a unique compact structure that minimizes the junctions between components, followed by removing possible leakage of refrigerant. To obtain a perfect sealing of glass in all indicators is used a modified PTFE gasket. This indicators series is characterized by an element sensitive to moisture which changes colour from green to yellow depending on the concentration of moisture in the system. The yellow colour indicates the presence of a high degree of humidity and therefore it is necessary to intervene with the replacing of the filter drier.
At the first start, the colour of the element sensitive to moisture can be yellow, both because of atmospheric moisture with which the indicator has come into contact, either due to moisture in the circuit. When the moisture content of the refrigerant is normalized through the dehydrator filter, the colour of the element becomes green. The brazing of the indicators to the system shall be done with a low melting point alloy. During this process do not point the flame directly towards the body keeping it cooled in order to avoid compromising the seal of the gaskets.