Sight glasses type FI

Sight glasses

Sight glasses are required in refrigeration systems to determine the lack of refrigerant in the system. They are generally installed in the liquid line after the dryer and before the expansion valve.

Sight glasses type FI:

In addition to a lack of refrigerant, sight glasses with a moisture indicator also indicate an impermissibly high water content in the refrigerant. The indicator changes color depending on the moisture content of the refrigerant.

• Green: Refrigerant is free from harmful water content.
• Pale green: The moisture level in the refrigerant has reached a level where replacement of the filter drier is recommended.
• Yellow: The filter drier needs to be replaced because the harmful water content is too high.

Sight glasses type SG:

Indicates a lack of refrigerant in the refrigeration system

Advantages

• FI / SG sight glasses are suitable for all refrigerants (except NH3 and those containing NH3).
• Permissible temperature range - 40 °C to + 100 °C.
• Maximum permissible operating pressure 60 bar.
• The humidity is optionally displayed via a centrally mounted indicator with an optimized mode of operation.
• Large viewing area for all versions, with and without an indicator. High temperature resistance.
• Easy-to-assemble design thanks to large spanner flats on sight glasses with flared connection.

Technical advice

Material designation according to DIN EN 12164 → CW 614 N When delivered, the indicator is yellow (because of the existing humidity). The indicator turns green when in contact with dry refrigerant.