Apply to be a TradeMaster!
Filter menu expanded

Filters

469 items
Reset

SORT

Product Availability

Show In Stock Only (181)

Product Type

Accessory (1)
Adapter (1)
Air Flow Switch (2)
Air Meter (1)
Anemometer (1)
Aspirator Bulb (1)
Carrying Case (2)
Controller (16)
Flange (1)
Float Switch (8)

Switch

DPDT (1)
DPDT (Optional) (1)
DPST (1)
SPDT (62)
SPST (2)

Price Range

Under $1 (1)
$1 to $5 (1)
$5 to $10 (4)
$10 to $15 (4)
$15 to $20 (3)
$20 to $25 (11)
$25 to $30 (7)
$30 to $35 (7)
$35 to $40 (13)
$40 to $45 (3)

Dwyer

Help Face
Need a little help?
469 items
Grid
List
Compare
Product Image of Explosion-Proof Differential Pressure Switch (.07" - .15" W.C.)
$506.97 each
In Stock
Get 2 by Tomorrow, Aug 19
In Stock
Get 2 by Tomorrow, Aug 19
Compare
Product Image of 3-5/32" Averaging Flow Sensor
3-5/32" Averaging Flow Sensor
SKU: PAFS-1002
Dwyer
SKU: PAFS-1002
Brand: Dwyer
$12.54 each
In Stock
Get 2 by Thu, Aug 20
In Stock
Get 2 by Thu, Aug 20
Compare
Product Image of Large Diaphragm Pressure Switch, Visual Set Point, SPDT (.2" - 1.0" W.C.)
$772.05 each
In Stock
Get 5 by Thu, Aug 20
In Stock
Get 5 by Thu, Aug 20
Compare
Product Image of Digital Differential Manometer (+/-60" W.C.)
$236.17 each
In Stock
Get 2 by Thu, Aug 20
In Stock
Get 2 by Thu, Aug 20
Compare
Product Image of Low Differential Pressure Switch, SPDT (3.0" - 22.0" W.C.)
$130.37 each
In Stock
Get 3 by Thu, Aug 20
In Stock
Get 3 by Thu, Aug 20
Compare
Product Image of Straight Stainless Steel Pitot Tube (18" Insertion Length)
$296.83 each
In Stock
Get 4 by Thu, Aug 20
In Stock
Get 4 by Thu, Aug 20
Compare
Product Image of Split Core Current Transducer, 100/150/200A Input (4-20 mA Output)
$51.48 each
In Stock
Get 1 by Tomorrow, Aug 19
In Stock
Get 1 by Tomorrow, Aug 19
NTC Probe, 304 SST, 5' Length
SKU: TS-8T
Dwyer
SKU: TS-8T
Brand: Dwyer
$28.49 each
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Compare
Product Image of Wet/Wet Differential Pressure Transmitter, 4-20 mA (0 to 25 PSID)
Wet/Wet Differential Pressure Transmitter, 4-20 mA (0 to 25 PSID)
SKU: 629C-03-CH-P2-E5-S1
Dwyer
SKU: 629C-03-CH-P2-E5-S1
Brand: Dwyer
(1)
$615.63 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Solid Core Current Transducer, 10/20/50A Input (4-20 mA Output)
$42.47 each
In Stock
Get 2 by Tomorrow, Aug 19
In Stock
Get 2 by Tomorrow, Aug 19
Compare
Product Image of Intrinsically Safe Handheld Digital Manometer (0 - 20.0" W.C.)
$446.98 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Low Cost Timer Controller (6 Channels)
Low Cost Timer Controller (6 Channels)
SKU: DCT506A
Dwyer
SKU: DCT506A
Brand: Dwyer
$235.21 each
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Compare
Product Image of 18/0/18 Slack Tube Manometer
18/0/18 Slack Tube Manometer
SKU: 1211-36
Dwyer
SKU: 1211-36
Brand: Dwyer
$254.51 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of 1/4 DIN Temperature/Process Controller (Dual Relay Outputs)
$212.91 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Magnehelic Differential Pressure Gage (0 - 10.0" W.C.)
$115.87 each
In Stock
Get 3 by Thu, Aug 20
In Stock
Get 3 by Thu, Aug 20
Compare
Product Image of Magnehelic Differential Pressure Gage (2.0" - 0" - 2.0" W.C.)
$119.18 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Intrinsically Safe Handheld Digital Manometer (0 - 10.0" W.C.)
$554.81 each
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Compare
Product Image of 1/8" NPT Filter Vent Plug
1/8" NPT Filter Vent Plug
SKU: A-331
Dwyer
SKU: A-331
Brand: Dwyer
$37.15 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Magnehelic Differential Pressure Gage (.05" - 0" - .20" W.C.)
$121.74 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Brass Bourdon Tube SPDT Pressure Switch w/ Snap Action Switch & Adj. Deadband (0 - 30" HG VAC)
$1,167.02 each
In Stock
Get 1 by Tomorrow, Aug 19
In Stock
Get 1 by Tomorrow, Aug 19
Compare
Product Image of Low Differential Pressure Switch, SPDT (1.5" - 5.0" W.C.)
$165.57 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Master Controller (6 Channels)
Master Controller (6 Channels)
SKU: DCT1006
Dwyer
SKU: DCT1006
Brand: Dwyer
$393.34 each
In Stock
Get 3 by Thu, Aug 20
In Stock
Get 3 by Thu, Aug 20
Compare
Product Image of Static Pressure Tip, Stainless Steel for 1/4" Metal Tubing
$113.61 each
In Stock
Get 2 by Thu, Aug 20
In Stock
Get 2 by Thu, Aug 20
Compare
Product Image of 1/2" NPT Low-Flow Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch, w/ Brass Tee
$379.51 each
In Stock
Get 1 by Tomorrow, Aug 19
In Stock
Get 1 by Tomorrow, Aug 19
Compare
Product Image of LPG3 Low Pressure Gage, Bottom Mount, 1.6% FS Accuracy (0 - 15" W.C.)
$150.37 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Timer Controller (10 Channels)
Timer Controller (10 Channels)
SKU: DCT610
Dwyer
SKU: DCT610
Brand: Dwyer
$284.28 each
In Stock
Get 5 by Thu, Aug 20
In Stock
Get 5 by Thu, Aug 20
Compare
Product Image of 2" NPT Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch, w/out Tee
$351.15 each
In Stock
Get 1 by Tomorrow, Aug 19
In Stock
Get 1 by Tomorrow, Aug 19
Compare
Product Image of Digihelic 3-in-1 Differential Pressure Controller (0 - 2.5" W.C.)
$663.08 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Digital Manometer w/ Air Velocity and Flow Modes (0 - 1.00" W.C.)
$505.70 each
In Stock
Get 2 by Thu, Aug 20
In Stock
Get 2 by Thu, Aug 20
Compare
Product Image of Low Cost Timer Controller (10 Channels, DC)
Low Cost Timer Controller (10 Channels, DC)
SKU: DCT510ADC
Dwyer
SKU: DCT510ADC
Brand: Dwyer
$277.37 each
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Compare
Product Image of Brass External Float Chamber Liquid Level Switch, Polypropylene Spherical Float
$443.34 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Stainless Steel Pitot Tube (5/16" Dia., 60-5/8" Insertion Length)
$240.62 each
In Stock
Get 1 by Tomorrow, Aug 19
In Stock
Get 1 by Tomorrow, Aug 19
Compare
Product Image of Master Controller (22 Channels)
Master Controller (22 Channels)
SKU: DCT1022
Dwyer
SKU: DCT1022
Brand: Dwyer
$580.61 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of DM Series Digital Differential Pressure Transmitter (0 - 0.25" W.C.)
$162.85 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of 40/400 SCFH RMB Air Flowmeter, Stainless Steel Valve
$102.77 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Master Controller (10 Channels)
Master Controller (10 Channels)
SKU: DCT1010
Dwyer
SKU: DCT1010
Brand: Dwyer
$467.19 each
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Out of Stock
Get it by Wed, Sep 2 - Thu, Sep 10
Compare
Product Image of Magnehelic Differential Pressure Indicating Transmitter, Max 10 PSI (0 - 1.0" W.C.)
$637.89 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Low Differential Pressure Switch, SPDT (5.0" - 44.0" W.C.)
$135.38 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of 1" FNPT Plastic Flowmeter (3 - 30 GPM)
1" FNPT Plastic Flowmeter (3 - 30 GPM)
SKU: HFPC-3-4
Dwyer
SKU: HFPC-3-4
Brand: Dwyer
$517.65 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Compare
Product Image of Flotect Stainless Steel Explosion-Proof SPDT Liquid Level Switch, Cylindrical Side Wall Mount
$589.83 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of 2000 Series Differential Pressure Gauge (0 - 4" W.C.)
$92.95 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Stainless Steel Pitot Tube (5/16" Dia., 18-5/8" Insertion Length)
$148.63 each
In Stock
Get 2 by Tomorrow, Aug 19
In Stock
Get 2 by Tomorrow, Aug 19
Compare
Product Image of Magnehelic Differential Pressure Gage (0 - 5 psi)
$131.24 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Liquid Level Switch w/ Weatherproof Enclosure
$198.52 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of DM Series Digital Differential Pressure Transmitter (0 - 3" W.C.)
$162.85 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Solid Core Current Transducer, 10/20/50A Input (0-10 V Output)
$34.26 each
In Stock
Get 4 by Thu, Aug 20
In Stock
Get 4 by Thu, Aug 20
Compare
Product Image of 0.5/5 LPM RMA Air Flowmeter, Stainless Steel Valve
0.5/5 LPM RMA Air Flowmeter, Stainless Steel Valve
SKU: RMA-26-SSV
Dwyer
SKU: RMA-26-SSV
Brand: Dwyer
$81.19 each
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Backorder
Get it by Thu, Sep 17 - Thu, Oct 15
Compare
Product Image of Digital Manometer w/ Air Velocity and Flow Modes (0 - 200.00" W.C.)
$308.77 each
In Stock
Get 1 by Thu, Aug 20
In Stock
Get 1 by Thu, Aug 20
Resources
FAQs, Manuals & Videos
Articles
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.