Sight glasses with moisture indicator

Overview – ConstructionInstallationCatalogue

sight glasses with moisture indicator for refrigerants
Indicators with moisture sensitive element are normally installed in the liquid line between the filter drier and the expansion valve to monitor the condition of the refrigerant.

Level Indicator Refrigerant fluid moisture level, in ppm
R22 R134a R404A R407C R410A R507
SAFE GREEN <60 <75 <30 <30 <30 <30
WARNING CHARTREUSE 60 75 30 30 30 30
DANGER YELLOW >60 >75 >30 >30 >30 >30


Available versions

IGLOO indicators have a complitely hermetic construction to prevent refrigerant leakage. It’s not possible to dissassembly IGLOO indicators because the glass is clamped into the brass body and sealed thanks to a ring of special PTFE (Teflon®).

100% tested: max leak 1 gram/year

IGLOO sight glasses are tested one-by-one against leakage with helium up to 70bar (1,015psi) and we recommend a Maximum Working Pressure MWP of 48bar (700psi).
During lab tests IGLOO sight glasses broke at the impressive pressure of 290bar (4,200psi) without explode: the security factor adopted is more than 6X, among the highest in the industry.


IGLOO glass indicators are suitable for all the most common CFC, HCFC and HFC refrigerants such as R22, R134a, R404, R410, R507 and Carbon Dioxide CO2 R744 (sub-critical). Not suitable for ammonia R717.


  1. sweat version have two copper swaged connection suitable for brazing using common alloys such as Cu-Ag or Cu-P. In case of brazing with aluminum tubes we recommend the use of Zn-Al alloys: enquiry our technical dept for more information about
  2. the extra-long and extra-thick ODS swaged connection reduce the possibility of damaging both the moisture indicating element and the PTFE gasket
  3. threaded version have standard SAE Flare connections, male-to-female (external-to-internal) or male-to-male (external-to-external).
  4. by adopting an optimal forging with extremely high mechanical strength the overall design is characterized by a total weight reduction: the body is up to 30% lighter comparing to the competition and the burst pressure (290bar or 4,200psi) is one of the highest among the industry
  5. only one indicator for all the most common refrigerants: R22, R407C, R410A, R134a, R404A, R507, R744, etc.. The color of the wet and dry condition is very easy to distinguish, because the difference is very wide and color change is reversible as often as moisture level in the circuit varies

Color changing element

The change in color of the sensitive element is calibrated at a value in parts per million of moisture for each refrigerant considering the best industry standards, such as ARI 710-86, DIN 8948 and the statements published by the Association of European Refrigeration Components Manufacturers.
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