Ashcroft 82143 Pressure Gauge 3.5 in Dial Npt Lower Mount

Product Description

The ASHCROFT 82143 is a liquid-filled analog pressure gauge designed for accurate vacuum and compound pressure measurement in demanding trade applications. It features a 3.5-inch dial with a range of -30 to 0 to 30 inches of mercury (in Hg), making it suited for vacuum, refrigeration, and HVAC system diagnostics. The stainless steel case provides corrosion resistance in wet or chemically active environments. Liquid filling dampens needle vibration, extending service life and improving readability on systems with pulsating pressures. Accuracy is rated at 1 percent of scale. A licensed HVAC technician, plumber, or mechanical contractor would typically install this gauge on suction lines, vacuum applications, or low-pressure piping systems.

This gauge is commonly used in residential and light commercial HVAC systems, refrigeration circuits, plumbing vacuum applications, and process piping where compound pressure monitoring is required. The 1/4-inch NPT lower-mount connection allows direct installation into standard threaded ports at the base of the gauge, keeping the dial face oriented upward for easy reading. It is well suited for panel mounting or direct pipe installation in mechanical rooms, rooftop units, or equipment skids.

Key Features

• Compound pressure range: -30 to 0 to 30 in Hg for vacuum and positive pressure measurement
• Liquid-filled case dampens vibration and protects internals in pulsating-pressure environments
• Stainless steel case resists corrosion in wet or chemically active service conditions
• 1 percent of scale accuracy for reliable diagnostic and monitoring readings
• 3.5-inch analog dial provides clear readability in field conditions
• 1/4-inch NPT lower-mount connection fits standard threaded ports

Compatibility

Designed as an OEM-style replacement or upgrade gauge for residential and commercial HVAC, refrigeration, and plumbing systems requiring a 1/4-inch NPT lower-mount compound vacuum gauge with a 3.5-inch dial.

Installation Notes

Installation is typically performed by a licensed HVAC technician, refrigeration mechanic, or journeyman plumber. Isolate and de-pressurize the system fully before removing any existing gauge or fitting. Apply appropriate thread sealant to the NPT connection per the applicable IPC or IFGC guidelines, ensuring compatibility with the system media. Do not over-tighten the threaded connection; use a wrench on the gauge hex fitting only, not on the case body.