Monitoring sight glass LFSG series

level indicatorfor refrigerationthreaded

Product overview
The sight glass is used on the liquid pipeline of the refrigeration and air-conditioning unit. It is installed behind the dryer to detect the flow of the refrigerant, the water content in the refrigerant and the flow of the lubricating oil in the oil return line of the oil separator. It is equipped with a wetness indicator, and the water content is displayed intuitively by color.

Parameters
General | Value
Applicable refrigerant: Commonly used refrigerants such as HCFC and HFC.
Max. working pressure: 4.5MPa
Max. proof pressure: 6.8MPa
Ambient temperature range: -50℃~+80℃
Applicable Medium Temperature: -40℃~+80℃

Features

• High-precision color-changing indicator and wide-angle clear glass cover ensure accurate identification.
• Brass welding, strong and corrosion-resistant, explosion-proof press fit to ensure safety.
• The sealing parts are made of high-performance PTFE, and 100% leakage test is conducted to ensure no leakage.
• Design of circular indicating paper, cancellation of adapter, low pressure loss.
• The connection has optional screw and weld, and is compatible with HCFC, HFC and corresponding lubricating oil.

Dimension / Model naming
Model naming LFSG-a-b a stands for pipe size, b stands for pipe form.
a can be 4(1/4"), 6(3/8"), 8(1/2"), 10(5/8"), 12(3/4"), 14(7/8"), 18(1-1/8").
b can be no=ODF ODF 1=SAE 2=Male Femal

Dimension table (selected rows)
Model | Pipe size | L | L1 | H | D | d | M | Male | Female
LFSG-4 | 1/4" | 100 | 7 | 23 | 26.5 | 6.5 | — | — | —
LFSG-4-1 | 1/4" (SAE) | 64 | — | 23 | 26.5 | — | 7/16-20UNFF | — | —
LFSG-4-2 | 1/4" (Male/Female) | 59 | — | 24.5 | 26.5 | — | — | — | —
LFSG-6 | 3/8" | 118 | 8 | 23 | 26.5 | 10.1 | — | — | —
LFSG-6-1 | 3/8" (SAE) | 70 | — | 23 | 26.5 | — | 5/8-18UNF | — | —
LFSG-6-2 | 3/8" (Male/Female) | 65 | — | 29 | 26.5 | — | — | — | —
LFSG-8 | 1/2" | 144 | 10 | 28 | 26.5 | 12.8 | — | — | —
LFSG-8-1 | 1/2" (SAE) | 78 | — | 28 | 26.5 | — | 3/4-16UNFF | — | —
LFSG-8-2 | 1/2" (Male/Female) | 70 | — | 31.5 | 26.5 | — | — | — | —
LFSG-10 | 5/8" | 150 | 14 | 31 | 26.5 | 16.1 | — | — | —
LFSG-10-1 | 5/8" (SAE) | 78 | — | 31 | 26.5 | — | 7/8-14UNF | — | —
LFSG-10-2 | 5/8" (Male/Female) | 78 | — | 37 | 30 | — | — | — | —
LFSG-12 | 3/4" | 166 | 16 | 34 | 31.5 | 19.1 | — | — | —
LFSG-12-1 | 3/4" (SAE) | 94 | — | 34 | 31.5 | — | 1-1/16-14UNF | — | —
LFSG-14 | 7/8" | 172 | 17 | 37 | 31.5 | 22.3 | — | — | —
LFSG-18 | 1-1/8" | 212 | 18 | 42 | 31.5 | 28.7 | — | — | —

Comparison table of refrigerant with water content and color
Medium | 25℃: Green/dry / Intermediate / Yellow/moist | 43℃: Green/dry / Intermediate / Yellow/moist
R22 / R502 | <30 / 30~120 / >120 | <50 / 50~200 / >200
R134a | <30 / 30~100 / >100 | <45 / 45~170 / >170
R404a | <20 / 20~70 / >70 | <25 / 25~100 / >100
R407C | <30 / 30~140 / >140 | <60 / 60~225 / >225
R507 | <15 / 15~60 / >60 | <30 / 30~110 / >110
R401A | <66 / 66~266 / >266 | <135 / 135~540 / >540
R410A | <60 / 60~280 / >280 | <75 / 75~420 / >420

Documents summary
Product datasheet and certificates are available (PDF documents listed separately).

Caractéristiques / spécifications techniques

• Applicable refrigerants: HCFC and HFC families.
• Max. working pressure: 4.5 MPa.
• Max. proof pressure: 6.8 MPa.
• Ambient temperature range: -50℃ to +80℃.
• Applicable medium temperature: -40℃ to +80℃.
• Wetness indicator: high-precision color-changing indicator to display water content visually.
• Body material and sealing: brass welded body, PTFE sealing parts, 100% leakage tested.
• Connection options: screw or weld; SAE and various thread options available for certain models.
• Designed for low pressure loss and compatibility with refrigerant lubricating oils.