Ashcroft 92958XLL Pressure Gauge 4.5 in 30-0-30 Psi Rear Flange

Product Description

The ASHCROFT 92958XLL is a compound pressure gauge designed for monitoring both positive and negative pressure in a single instrument. With a 30-0-30 psi range, it reads vacuum on the left side of the dial and positive pressure on the right. The 4.5-inch analog dial provides easy readability at a distance, and the thermoplastic case offers corrosion resistance in a range of service environments. Accuracy is rated at 0.5 percent of scale, making it suitable for applications where close pressure monitoring is required. This gauge ships dry — no liquid fill — and uses a 0.25-inch rear thread connection with a rear flange mount. It is typically installed by HVAC technicians, plumbers, and mechanical contractors.

This compound gauge is well suited for residential and light commercial mechanical systems where both vacuum and positive pressure readings are needed on a single instrument. Common applications include refrigeration service, HVAC chilled water and hydronic systems, pump suction lines, and similar plumbing or mechanical piping installations. The rear flange mount allows the gauge to be panel- or wall-mounted flush against a surface, keeping the face visible and the connection recessed.

Key Features

• Compound 30-0-30 psi range reads both vacuum and positive pressure on one dial
• 4.5-inch analog dial for clear, at-a-distance readability
• 0.5 percent of scale accuracy for reliable pressure monitoring
• Thermoplastic case provides corrosion resistance without added weight
• Dry gauge — no liquid fill, suitable for environments where leakage is a concern
• Rear flange mount allows panel or surface mounting with a recessed 0.25-inch rear thread connection

Compatibility

Designed as an OEM-style replacement or direct-install compound pressure gauge for mechanical piping, HVAC, and plumbing systems requiring a 0.25-inch rear-threaded, rear-flange-mount instrument with a 4.5-inch dial.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or qualified mechanical contractor in accordance with applicable local codes and ASME B40.100 gauge installation guidelines. Shut off system pressure and relieve line pressure to zero before connecting or removing the gauge. Use an appropriate thread sealant on the 0.25-inch NPT rear connection and avoid over-tightening, which can crack the thermoplastic case or distort the bourdon tube. Do not use this gauge in applications involving fluid compatibility issues with thermoplastic materials without verifying material suitability first.