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Dwyer

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Product Image of Magnehelic Differential Pressure Gage (0 - 15.0" W.C.)
$87.75 each
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Product Image of Air Filter Kit
Air Filter Kit
SKU: A-605
Dwyer
SKU: A-605
Brand: Dwyer
$83.73 each
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Product Image of Minihelic II Differential Pressure Gage (0 - 2.0" W.C.)
$84.58 each
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Product Image of Digital Farenheit Temperature Switch, 16A (110V)
$174.16 each
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Product Image of Vaneometer Swing Vane Anemometer (25-400 FPM)
Vaneometer Swing Vane Anemometer (25-400 FPM)
SKU: 480-DWYER
Dwyer
SKU: 480-DWYER
Brand: Dwyer
$53.74 each
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Product Image of 12" Temperature Sensor Duct Mount Probe, 10K Ohm Type II Thermistor
$22.99 each
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Product Image of Magnehelic Differential Pressure Gage (.125" - 0" - .125" W.C.)
$88.55 each
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Product Image of Low Differential Pressure Switch, SPDT (.5" - 2.0" W.C.)
$126.12 each
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Product Image of Digital Farenheit Temperature/Process Indicator, PTC Thermistor Input (110V)
$64.54 each
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Product Image of 6" Straight Stainless Steel Static Pressure Tip w/ Mounting Flange
$12.48 each
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Product Image of Magnehelic Differential Pressure Gage (0.5" - 0" - 0.5" W.C.)
$112.02 each
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Product Image of Static Pressure Fitting for 3/16" & 1/8" ID Plastic/Rubber Tubing
$12.75 each
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Product Image of Portable Static Pressure Tip for 3/16" ID Rubber/Plastic Tubing w/ 4" Insertion
$22.89 each
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Product Image of Static Pressure Tip for 3/16" & 1/8" ID Plastic or Rubber Tubing
$27.74 each
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Product Image of Low Differential Pressure Switch, SPDT (.15" - .5" W.C.)
$110.02 each
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Product Image of 1" Midwest Bronze Sight Flow Indicator
1" Midwest Bronze Sight Flow Indicator
SKU: SFI-100-1
Dwyer
SKU: SFI-100-1
Brand: Dwyer
$306.46 each
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Product Image of Digital Timer (115 VAC)
Digital Timer (115 VAC)
SKU: LCT316-100
Dwyer
SKU: LCT316-100
Brand: Dwyer
$69.19 each
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Product Image of Flotect Vane Operated SPDT Flow Switch w/ 18" 18 AWG Wires (150 PSIG)
$134.39 each
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Product Image of Aspirator Bulb for Calibration & Leak Check Testing
$38.86 each
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Product Image of Static Pressure Pickup Ceiling Mount
Static Pressure Pickup Ceiling Mount
SKU: A-419A
Dwyer
SKU: A-419A
Brand: Dwyer
$24.84 each
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Product Image of Explosion-Proof Differential Pressure Switch (4.0" - 20.0" W.C.)
$368.55 each
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Product Image of Magnehelic Flush Mounting Kit for Magnehelic Gages
$47.24 each
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Product Image of 1/2" Midwest Bronze Sight Flow Indicator
1/2" Midwest Bronze Sight Flow Indicator
SKU: SFI-100-1/2
Dwyer
SKU: SFI-100-1/2
Brand: Dwyer
$217.91 each
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Product Image of Explosion-Proof Differential Pressure Switch (.15" - .5" W.C.)
$369.10 each
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Product Image of Magnehelic Differential Pressure Gage (0 - 8.0" W.C.)
$107.88 each
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Product Image of 1/16 DIN Temperature/Process Controller, Relay Output 1 & 2 (100 to 240 VAC)
$171.97 each
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Product Image of Magnehelic Differential Pressure Gage (.25" - 0" - .25" W.C.)
$112.02 each
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Product Image of Low Differential Pressure Switch, SPDT (.07" - .22" W.C.)
$112.75 each
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Product Image of Adjustable Air Flow Switch w/ Stainless Steel Vane
$157.70 each
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Product Image of 3-1/4" x 2-3/8" Static Pressure Pickup for Roof/Outside Mount
$49.65 each
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Product Image of Gas Pressure Switch (4.0" - 20.0" W.C.)
Gas Pressure Switch (4.0" - 20.0" W.C.)
SKU: 1996-20
Dwyer
SKU: 1996-20
Brand: Dwyer
$195.79 each
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Product Image of 2" Sight Flow Indicator
2" Sight Flow Indicator
SKU: SFI-100-2
Dwyer
SKU: SFI-100-2
Brand: Dwyer
$487.09 each
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Product Image of Static Pressure Tip, Stainless Steel w/ Mounting Flange for 3/16" Tubing (6" Insertion)
$18.41 each
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Product Image of Dual Stage Weatherproof Digital Temperature Switch, 90 to 255 VAC, w/ Probe
$168.42 each
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Product Image of Static Pressure Tip for 1/4" Metal Tubing Connection
$20.45 each
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Product Image of 6-0-6" UTube Manometer w/ Clips
6-0-6" UTube Manometer w/ Clips
SKU: 1221-12-W/M
Dwyer
SKU: 1221-12-W/M
Brand: Dwyer
(1)
$98.93 each
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Product Image of Adjustable Differential Pressure Switch w/ M20 Connection (.08" - 1.20" W.C.)
$56.99 each
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Product Image of Replacement Reed Switch for Water Leak Detector
Replacement Reed Switch for Water Leak Detector
SKU: WM-ACC-RS
Dwyer
SKU: WM-ACC-RS
Brand: Dwyer
$33.32 each
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Product Image of 3-Way Plastic Vent Valve 1/8" NPT to 1/4" Metal Tubing
$44.93 each
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Product Image of 3/16" ID x 5/16" OD Clear Vinyl Tubing (45 PSI Max @ 73-Degree (F))
$0.99 each
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Product Image of LPG4 Low Pressure Gage, Bottom Mount 1.5% FS Accuracy (0 - 15" W.C.)
$107.23 each
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Product Image of Gray Outdoor Static Pressure Sensor w/ 50' Vinyl Tubing
$113.15 each
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Product Image of Aluminum Surface Mounting Plate for Magnehelic Gage
$32.18 each
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Product Image of Large Diaphragm Pressure Switch w/ Visual Set Point Adjustment (.05" - .25" W.C.)
$569.99 each
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Product Image of Static Pressure Tip w/ 6" Probe
Static Pressure Tip w/ 6" Probe
SKU: A-421
Dwyer
SKU: A-421
Brand: Dwyer
$55.49 each
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Product Image of Differential Pressure Switch w/ Manual Reset (3.0" - 11.75" W.C.)
$169.67 each
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Product Image of 1/2" NPT Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch w/ Brass Tee
$400.64 each
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Product Image of 1" NPT Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch, w/ Brass Tee
1" NPT Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch, w/ Brass Tee
SKU: V6EPB-B-S-3-B
Dwyer
SKU: V6EPB-B-S-3-B
Brand: Dwyer
$357.08 each
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More About Dwyer

Dwyer Instruments traces its roots to 1931, when the F.W. Dwyer Manufacturing Company was founded in Chicago to produce liquid filled manometer test instruments. In 1953 the company developed the Magnehelic gauge, which grew into its flagship product and helped drive the company's expansion.

As the business grew, Dwyer moved its headquarters from Chicago to Michigan City, Indiana, where it remains today, with additional offices supporting customers across Asia, Europe, and Australia. The company now manufactures instrumentation for HVAC and process automation markets.

Product Lines

Dwyer's pressure product line includes the Series 2000 Magnehelic differential pressure gauges and Series MSX Magnesense differential pressure transmitters, both used to measure low air or non-corrosive gas pressure. The catalog also covers manometers, flow meters, flow switches, and flow indicators for measuring flow rate in liquids and gases.

Beyond pressure and flow, Dwyer supplies controllers, data loggers, remote displays, and sensors for temperature, level, and air velocity, along with calibration services and accessories for the instruments it manufactures.

Why Contractors Specify Dwyer

Magnehelic gauges have been used in the field since the 1950s for tasks like filter monitoring, duct static pressure checks, and cleanroom pressure differential readings, giving contractors a design with a long track record. Because the gauge uses a frictionless internal movement, it reads pressure without external power.

Carrying pressure, flow, level, and temperature instruments under a single brand simplifies sourcing replacement parts and matching new installations to existing equipment already in the field. That range makes Dwyer instruments a common choice for HVAC balancing, air quality monitoring, and process control work.

How to Choose Dwyer Products

Begin with what needs to be measured: pressure, flow, level, or temperature, since Dwyer's product lines are organized around these measurement types. For pressure applications, decide between a mechanical gauge like the Series 2000 Magnehelic for local visual readings or a transmitter like the Series MSX Magnesense when a signal needs to reach a building automation or control system.

Check the pressure range, accuracy, and gas compatibility required for the application, and confirm whether the instrument will be exposed to corrosive gases before selecting a model. Mounting location and available power at the install point should also factor into the choice between a gauge and a transmitter.

Frequently Asked Questions

What is a Magnehelic gauge used for?

It measures low differential air or non-corrosive gas pressure, whether positive, negative, or differential, and is commonly used for filter monitoring, duct static pressure, and cleanroom pressure differential readings.

What is the difference between the Series 2000 Magnehelic gauge and the Series MSX Magnesense transmitter?

The Series 2000 is a mechanical dial gauge for local visual reading, while the Series MSX is an electronic transmitter that sends a signal to a building automation or control system.

Does a Magnehelic gauge need external power?

No, the Magnehelic gauge uses a frictionless internal movement and does not require external power to operate.

Where is Dwyer Instruments headquartered?

Dwyer is headquartered in Michigan City, Indiana, with additional offices in Asia, Europe, and Australia.

What industries rely on Dwyer instrumentation?

Dwyer instruments are used in HVAC and process automation applications, including air quality, flow, level, temperature, and process control monitoring.