Ashcroft 83226 Pressure Gauge 3.5 in Dial Npt Lower Mount

Product Description

The ASHCROFT 83226 is a liquid-filled analog pressure gauge designed for accurate pressure and vacuum monitoring in mechanical, HVAC, plumbing, and industrial service applications. The gauge features a 3.5-inch dial with a compound range of -30 to 0 to 15 inches Hg (in Hg), a stainless steel case for corrosion resistance, and a lower-mount 1/4-inch NPT connection. Liquid fill dampens needle vibration and reduces internal wear in high-pulsation or vibrating systems. The 1% of scale accuracy rating makes it suitable for diagnostic and commissioning work where reliable readings matter.

This gauge is used in residential and commercial applications where both vacuum and low positive pressure must be monitored from a single instrument. Typical install scenarios include refrigeration system service, low-pressure gas piping, hydronic heating systems, pump suction monitoring, and HVAC equipment commissioning. The lower-mount configuration allows direct installation into a tee or manifold fitting in a panel or piping assembly. The 3.5-inch dial is large enough for quick field readings without removing access panels.

Key Features

• Compound range: -30 to 0 to 15 inches Hg for vacuum and low positive pressure in a single gauge
• Liquid-filled case dampens needle vibration in pulsating or high-cycle systems
• Stainless steel case resists corrosion in wet and outdoor service environments
• 1% of scale accuracy for reliable diagnostic and commissioning readings
• 3.5-inch analog dial for clear field readability
• Lower-mount 1/4-inch NPT connection fits standard pipe fittings and manifolds

Compatibility

Designed as an OEM-style replacement or service gauge for low-pressure piping systems, HVAC equipment, and mechanical assemblies using standard 1/4-inch NPT lower-mount gauge ports.

Installation Notes

Installation is typically performed by a licensed HVAC technician, plumber, or refrigeration mechanic. Shut off and depressurize the system completely before removing or installing any pressure gauge. Apply thread sealant rated for the service fluid to the NPT threads before installation — do not use PTFE tape on compound vacuum gauges unless confirmed compatible with the system. Verify the pressure range of the gauge matches the expected operating range of the system before placing in service.