Series-1996

Supported Applications

The Dwyer Series 1996 Gas Pressure Switches are designed for use with natural, manufactured, or LP gas and air. These switches serve as reliable interlocks for gas-fired furnaces and equipment, providing visible set point adjustment and on-off indicators to monitor high or low gas pressure conditions.

Operating Conditions & Performance

The series operates within an ambient temperature range of -30°F (-34.4°C) to 110°F (43.3°C). For dry gas or dry air applications, the process temperature limit is specified as 32°F/0°C to 110°F/43.3°C. The switch supports continuous pressure up to 45 in w.c. (11.2 kPa) with a surge rating of 10 psig (68.95 kPa). Two primary measurement ranges are available: Model 1996-5 covers 1.4 to 5.5" w.c., and Model 1996-20 covers 4 to 20" w.c.

Performance characteristics include specific dead band values dependent on the set point, as documented in series specifications:

• Model 1996-5 (Low Range): Set points from 1.5 to 5 inches water column feature approximate dead bands ranging from 0.10 to 0.19.
• Model 1996-20 (High Range): Set points from 4 to 20 inches water column feature approximate dead bands ranging from 0.15 to 0.41.

Configuration Options

The Series 1996 is configured with an SPDT switch offering Normally Open (NO) or Normally Closed (NC) contacts via a 3-screw terminal block connection labeled Common, Normally Open, and Normally Closed. The electrical rating supports up to 15 amps at 120-480 VAC, 60 Hz.

Physical configuration includes:

• Housing: Aluminum die casting with steel stamping; zinc-plated for 200-hour salt spray resistance. Dimensions are approximately 3-1/8" (79.38 mm) in height and 3-1/2" (88.90 mm) in width.
• Process Connections: The bottom connection provides dual threading options: 1/8" female NPT or 1/4" male NPT for pipe nipple or coupling attachment.
• Vent Connection: A top port identified as LO-PR is provided to vent the diaphragm chamber to outside atmosphere or a combustion chamber. The HI-PR port is not used in fuel gas switches and remains unconnected to the diaphragm chamber.
• Enclosure: Features a removable conduit enclosure cover with a 7/8" (22.23 mm) opening for 1/2" conduit connection, housing the visible set point adjustment screw.

The series holds UL and C.S.A. listing as well as F.M. approval and CE compliance. Wetted materials should be confirmed by consulting the factory.

Key Product Differences

Differences within the Series 1996 are defined primarily by pressure range models:

• Model 1996-5: Configured for a set point adjustment range of 1.4 to 5.5 inches water column.
• Model 1996-20: Configured for a set point adjustment range of 4 to 20 inches water column.

The series documentation notes that explosion-proof alternatives are available in Series 1950 and Series 1950G. Process tubing options may be sourced from Gage Tubing Accessories catalogs. Installation requires mounting the switch with the diaphragm in a horizontal position, unless other orientations are confirmed by consulting the factory.