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Parker PSG-4S sight glass with solid copper extended ends and O-ring design

Parker

Parker PSG-4S Personal Protective Equipment

SKU CH-S6J8-8PABF MPN PSG-4S

A sight glass with solid copper extended ends, a two-piece O-ring design and a 650 PSIG UL listing for secure sweat fitting installation

  • Clear flow visibility with 1/2 inch sweat fittings
  • Robust copper construction for long service life
  • Secure seal via 2-piece O-ring design
  • UL listed for 650 PSIG working pressure
  • Compact 3.87 inch cut-out fits tight spaces

Sight Glass for Refrigerant Lines

The Parker PSG-4S is a sight glass designed for installation in refrigerant lines. It uses a sweat fitting type with solid copper extended ends for permanent brazed connections. The unit is UL listed for a maximum working pressure of 650 PSIG. It allows visual inspection of refrigerant flow and condition.

Technicians requiring a brazed inline sight glass

This component suits HVAC and refrigeration technicians who need a permanent, soldered installation on half-inch copper tubing. The two-piece design with an O-ring seal allows for internal cleaning or maintenance access. It is not intended for systems using flare or threaded connections. Installers needing a removable or clamp-on style should look at other designs.

Half-inch sweat fitting

The fitting connects to 1/2 inch copper tube via sweat brazing on both ends. The required cut-out length for the tubing is 3.87 inches, while the overall assembled length measures 4 22/25 inches. This specific dimension determines whether the glass fits the available space in the piping layout. Verify the cut-out measurement before purchase.

Highlights

  • Clear flow visibility with 1/2 inch sweat fittings
  • Robust copper construction for long service life
  • Secure seal via 2-piece O-ring design
  • UL listed for 650 PSIG working pressure
  • Compact 3.87 inch cut-out fits tight spaces

Specifications

BrandParker
ModelPSG-4S

Questions about this item

What pipe size and fitting type does the PSG-4S sight glass require for installation?

The PSG-4S uses a sweat fitting type with 1/2 x 1/2 inch connections and solid copper extended ends for direct soldering to matching copper tubing.

Can the PSG-4S be used in a system that still runs at the original 650 PSIG design pressure?

Yes, the PSG-4S is UL Listed for 650 PSIG, so it remains rated for the full design pressure of the existing system.

How can I verify the PSG-4S is sealed correctly after soldering it into the line?

Pressurise the system and watch through the glass for bubbles at the O-ring joint; a clear, bubble-free view confirms the 2-piece seal is holding.

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