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Flow Switches

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Product Image of 1/2" NPT Thermal Dispersion Flow Switch for 1/2" - 1-1/2" Pipe (6 ft Cable)
$377.17 each
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Product Image of 2" MNPT Sight Window
2" MNPT Sight Window
SKU: SFI-550-2
Dwyer
SKU: SFI-550-2
Brand: Dwyer
$102.95 each
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Product Image of Low-Flow Stainless Steel Explosion-Proof Mini-Size Flow Switch, Lead Free
$554.57 each
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Product Image of FS7-4S, 1-1/4" Flow Switch w/ Stainless Steel Body
$1,079.16 each
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Product Image of 1" FS-204W Liquid - Wet Paddle-Type Flow Switch
$663.10 each
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Product Image of FS6-W-1, 1" Flow Switch w/ NEMA 4X enclosure
$545.76 each
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Product Image of SPST Boiler Water Level Control, Close on Rise
$832.39 each
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Product Image of FS1-14, Replacement Gasket for FS1
$20.42 each
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Product Image of AF3-122, Paddle Kit for AF3
$38.50 each
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Product Image of FS7S-4R-4, Paddle Arm Kit
$220.00 each
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Product Image of FS7-VL-4R-4, Long Paddle Arm Kit
$265.09 each
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Product Image of Air Velocity Transmitter w/ LED Display (6" Probe)
$915.99 each
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Product Image of Air Velocity Transmitter (3% Accuracy)
Air Velocity Transmitter (3% Accuracy)
SKU: AVUL-3DA1
Dwyer
SKU: AVUL-3DA1
Brand: Dwyer
$337.45 each
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Product Image of Thermo Air Flow Switch (24 VDC)
Thermo Air Flow Switch (24 VDC)
SKU: AVFS-2
Dwyer
SKU: AVFS-2
Brand: Dwyer
$446.70 each
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Product Image of Air Velocity Transmitter (5% Accuracy)
Air Velocity Transmitter (5% Accuracy)
SKU: AVUL-5DA1
Dwyer
SKU: AVUL-5DA1
Brand: Dwyer
$215.62 each
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Product Image of 1/2" NPT Horizontal Mount Level Switch, 316 Stainless Steel Float
$469.32 each
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Product Image of 1/8" MNPT Vertical Level Switch, Buna-N Float, 316 Stainless Steel Stem
$73.69 each
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Product Image of 1" High Current Brass Flow Switch w/ Flexible Paddles
$222.76 each
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Product Image of 1" High Current Stainless Steel Flow Switch NEMA1 w/ Flexible Paddles (Double Switch)
$624.60 each
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Product Image of NPT Paddle Flow Switch w/ Conduit Electrical Connection
$94.10 each
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Product Image of Free Floating Sewage Water SPDT Level Switch (20 ft Cable)
$146.28 each
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Product Image of FS7-28S, Replacement Paddle for FS7-F4
$46.33 each
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Product Image of S-2, Switch Cover Replacement
$23.62 each
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Product Image of FS4-3D-17, Replacement SPDT Switch for Flow Switches
$36.47 each
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Product Image of FS7-4EL, 1-1/4" Flow Switch w/ NEMA 7 & 9 enclosure, w/extended paddle & paddle arm
$751.93 each
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Product Image of AF1-21, Replacement Gasket for Air Flow Switch
$10.54 each
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Product Image of AF1-122, Paddle Kit for AF1 & AF1-J
$47.50 each
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Product Image of FS8-WZ, 1" Flow Switch w/ ANSI terminal connections
$251.71 each
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Product Image of FS8-33, Replacement Switch
$133.00 each
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Product Image of 641 Series Air Velocity Transmitter (12" Probe)
$726.14 each
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Product Image of Timer Controller (22 Channels)
Timer Controller (22 Channels)
SKU: DCT622
Dwyer
SKU: DCT622
Brand: Dwyer
$524.00 each
In Stock
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Product Image of Flow Sensor for 4" Pipe
Flow Sensor for 4" Pipe
SKU: DS-300-4
Dwyer
SKU: DS-300-4
Brand: Dwyer
$435.94 each
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Product Image of 1" High Current Brass Flow Switch NEMA1 w/ Rigid Paddles (Single Switch)
$233.95 each
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Product Image of 1" Stainless Steel Flow Switch NEMA4 w/ Flexible Paddles (Small Turn Radius)
$662.37 each
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Product Image of Optical Level Switch, 316 Stainless Steel/Polysulfone
$213.99 each
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Product Image of 1" NPT Weatherproof Vane Operated Flow Switch
1" NPT Weatherproof Vane Operated Flow Switch
SKU: V7-WBS-30N
Dwyer
SKU: V7-WBS-30N
Brand: Dwyer
$139.52 each
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Product Image of FS7-4WL, 1-1/4" Flow Switch w/ NEMA 4X enclosure, w/extended paddle & paddle arm
$653.55 each
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Product Image of FS4-3T2-1, 1" Flow Switch w/ NPT body (Medium Flow Rate)
$296.97 each
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Product Image of FS4- 3J, 1" Flow Switch w/ BSPT connections
$213.08 each
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Product Image of FS5-D-3/4, 3/4 Flow Switch w/2 SPDT switches
$406.44 each
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Product Image of 641 Series Air Velocity Transmitter (6" Probe)
$726.14 each
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Product Image of AF1-S-122, Stainless Steel Paddle for Air Flow Switches
$71.75 each
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Product Image of FS7W-43, Replacement Gasket for Flow Switch
$78.00 each
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Product Image of SA2-7, Switch Cover Replacement
$327.17 each
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Product Image of AF2-122, Paddle Kit for AF2
$38.82 each
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Product Image of Dust Collector Timer Controller (10 Channels)
Dust Collector Timer Controller (10 Channels)
SKU: DCT1010DC
Dwyer
SKU: DCT1010DC
Brand: Dwyer
$479.14 each
In Stock
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Product Image of Low Cost Timer Controller (4 Channels)
Low Cost Timer Controller (4 Channels)
SKU: DCT504A
Dwyer
SKU: DCT504A
Brand: Dwyer
$190.65 each
Out of Stock
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Product Image of 19" Probe Capacitive Level Switch, Weatherproof
19" Probe Capacitive Level Switch, Weatherproof
SKU: CLS2-W11RK1-019
Dwyer
SKU: CLS2-W11RK1-019
Brand: Dwyer
$743.66 each
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More About Flow Switches
A flow switch is an instrument that monitors the flow of steam, air, or liquid. The flow switch sends a signal to a device, such as a pump, to turn on or shut off. Flow switches can be used for air conditioning, heating and hydronic systems, among other applications.

Air flow switches are used in applications that require low to high velocity, providing an economical way to detect change or loss of air flow velocity. This change or loss may be caused by a closed damper or fan inlet, loose fan wheel, slipped or broken fan belt, dirty or clogged filter, or an overload on a fan motor switch.

Liquid flow switches have a universal design and serve a wider range of applications, such as starting or stopping electrically operated equipment like signal lights, alarms, motors, and automatic burners. In addition, liquid flow switches are used for general purpose applications with environmental exposure or applications requiring a water-tight or dust-tight flow switch. The liquid-flow F61 Series flow switch, manufactured by Johnson Controls, responds to fluid flow in lines carrying water, ethylene glycol, or other nonhazardous fluids. It also responds to low fluid flow rates in applications with pipe sizes under 1" trade size.

Our website offers a vast selection of McDonnell & Miller Johnson Controls, Watts. and Taco flow switches that suit a wide range of residential, commercial, and industrial applications.