Ashcroft 83225 Pressure Gauge 3.5 in Dial 30 Hg Npt Lower

Product Description

The ASHCROFT 83225 is an analog vacuum pressure gauge designed for monitoring negative pressure in HVAC, plumbing, refrigeration, and industrial piping systems. It features a 3.5-inch dial face calibrated from 30 inches of mercury (Hg) to 0, with a stated accuracy of 1 percent of full scale. The stainless steel case provides corrosion resistance in wet or chemically active environments. Liquid-filled construction dampens pointer vibration and protects the internal bourdon tube movement from pulsation and shock, extending service life in demanding applications. Connection is via a 0.25-inch NPT lower-mount fitting, allowing direct in-line or panel installation. Licensed HVAC technicians, plumbers, and mechanical contractors are the primary installers.

This gauge is suited for vacuum service applications including refrigerant evacuation monitoring, vacuum pump performance verification, and low-pressure gas or fluid system diagnostics. The lower-mount NPT connection supports vertical or upright installations where the process connection enters from the bottom of the gauge. The analog dial provides at-a-glance readings without power requirements, making it practical for field service work, mechanical rooms, and permanent panel installations in both residential and light commercial systems.

Key Features

• 3.5-inch analog dial for clear readings at typical service distances
• Vacuum range: 30 Hg to 0, suitable for refrigeration evacuation and vacuum service
• 1 percent of full-scale accuracy for reliable diagnostic readings
• Liquid-filled movement dampens vibration and protects internal components from pulsation
• Stainless steel case resists corrosion in wet and chemically active environments
• 0.25-inch NPT lower-mount connection for direct in-line or panel installation

Compatibility

Designed as an OEM-style replacement or service gauge for vacuum and low-pressure monitoring applications using standard 0.25-inch NPT lower-mount fittings in HVAC, plumbing, refrigeration, and mechanical piping systems.

Installation Notes

Installation should be performed by a licensed HVAC technician, plumber, or qualified mechanical contractor. Isolate and depressurize the system completely before removing an existing gauge or making new connections. Apply thread sealant tape to NPT threads per standard practice, and do not overtighten the fitting, as stainless steel fittings can gall. Verify that the gauge range is appropriate for the system before returning the system to service.