Ashcroft 81408XLL Pressure Gauge 3.5 in 30-0-300 Psi Back Mount

Product Description

The ASHCROFT 81408XLL is an analog pressure gauge designed for industrial and mechanical service applications requiring accurate compound or positive pressure measurement. The gauge features a 3.5-inch dial with a 30-0-300 psi range, making it suitable for systems that experience both vacuum and positive pressure conditions. The stainless steel case provides corrosion resistance in demanding environments, while the bronze wetted parts are compatible with a broad range of non-corrosive media including water, oil, and air. Accuracy is rated at 1 percent of full scale. The 0.25-inch NPT center back mount configuration allows for direct panel or manifold installation without a separate adapter in most standard setups.

This gauge is commonly installed in HVAC systems, plumbing distribution lines, compressor systems, and light industrial fluid service where a durable, readable dial-type pressure indicator is required. The center back mount orientation is standard for panel-flush and inline manifold mounting. The dry, no-fill design simplifies installation in environments where glycerin or silicone fill could contaminate the process media or create maintenance complications. Licensed plumbers, HVAC technicians, and industrial pipefitters are the primary installers of this type of gauge.

Key Features

• 3.5-inch analog dial for clear, at-a-glance readings in the field
• 30-0-300 psi compound range covers both vacuum and positive pressure service
• 1 percent of full scale accuracy for reliable measurement in trade applications
• Stainless steel case resists corrosion and physical damage in harsh environments
• Bronze wetted parts compatible with water, air, oil, and other non-corrosive media
• Dry no-fill design eliminates fluid contamination risk and simplifies servicing
• Center back mount with 0.25-inch NPT connection suits standard panel and manifold installs

Compatibility

Designed as an OEM-style replacement or new-installation analog pressure gauge for HVAC, plumbing, and light industrial systems using standard 0.25-inch NPT center back mount fittings.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or qualified pipefitter in accordance with applicable local codes and ASME B40.100 gauge installation standards. Depressurize and isolate the system completely before removing any existing gauge or connecting the new unit. Use appropriate thread sealant on the NPT connection and tighten to a firm, leak-free fit without overtorquing the case. Do not use this gauge with strongly corrosive media, acetylene, or any service for which bronze wetted parts are not rated.