Apply to be a TradeMaster!
Filter menu expanded

Filters

151 items
Reset

SORT

Product Availability

Show In Stock Only (65)

Application

Air Flow (2)
Liquid Flow (67)
Replacement Part (28)

Size

1/2" (9)
3/4" (5)
1" (45)
1-1/4" (9)
1/8" (2)
2" (4)
6" (1)
12" (1)
19" (1)

Review Score

(22)
(3)
(2)

Price Range

$10 to $15 (3)
$20 to $25 (5)
$25 to $30 (2)
$30 to $35 (3)
$35 to $40 (3)
$45 to $50 (2)
$60 to $70 (1)
$70 to $80 (4)
$80 to $90 (2)
$90 to $100 (3)

Flow Switches

Help Face
Need a little help?
151 items
Grid
List
Compare
Product Image of FS1-J, High Sensitivity Flow Switch, 1/2" NPT (w/ BSPT Threads)
$366.42 each
In Stock
Get 1 by Mon, Jul 27
In Stock
Get 1 by Mon, Jul 27
Compare
Product Image of 3/4" NPT Flotect Explosion-Proof Mini-Size Brass SPDT Flow Switch w/ Brass Tee
$362.61 each
In Stock
Get 3 by Wed, Jul 29
In Stock
Get 3 by Wed, Jul 29
Compare
Product Image of FS7-4E, 1-1/4" Flow Switch w/ NEMA 7 & 9 enclosure
$846.93 each
In Stock
Get 1 by Mon, Jul 27
In Stock
Get 1 by Mon, Jul 27
Compare
Product Image of 1" Brass Flow Switch NEMA4 w/ Rigid Paddles (Double Switch)
$389.47 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
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 Tue, Jul 28
In Stock
Get 3 by Tue, Jul 28
Compare
Product Image of 1" Stainless Steel Flow Switch NEMA4 w/ Rigid Paddles (Small Turn Radius)
$676.45 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS1-17, Replacement Switch for Flow Switches
$144.94 each
In Stock
Get 1 by Mon, Jul 27
In Stock
Get 1 by Mon, Jul 27
Compare
Product Image of Side Wall Mount Liquid Level Switch, 304 Stainless Steel Cylindrical Float
$411.56 each
In Stock
Get 32 by Tomorrow, Jul 24
In Stock
Get 32 by Tomorrow, Jul 24
Compare
Product Image of Low Cost Timer Controller (10 Channels)
Low Cost Timer Controller (10 Channels)
SKU: DCT510A
Dwyer
SKU: DCT510A
Brand: Dwyer
$263.82 each
Out of Stock
Get it by Fri, Aug 7 - Fri, Aug 14
Out of Stock
Get it by Fri, Aug 7 - Fri, Aug 14
Compare
Product Image of FS4-3T-25, Paddle Kit for FS4-3T
$66.85 each
In Stock
Get 1 by Tomorrow, Jul 24
In Stock
Get 1 by Tomorrow, Jul 24
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, Jul 24
In Stock
Get 1 by Tomorrow, Jul 24
Compare
Product Image of FS7-28, Bronze Paddle Kit for FS7
$30.95 each
In Stock
Get 2 by Mon, Jul 27
In Stock
Get 2 by Mon, Jul 27
Compare
Product Image of Brass External Float Chamber Liquid Level Switch, Polypropylene Spherical Float
$443.34 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Flow Switch for Hydraulic Systems
Flow Switch for Hydraulic Systems
SKU: QVE1900U
Siemens
SKU: QVE1900U
Brand: Siemens
$156.20 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Flotect Stainless Steel Explosion-Proof SPDT Liquid Level Switch, Cylindrical Side Wall Mount
$589.83 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
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
In Stock
Get 1 by Tue, Jul 28
In Stock
Get 1 by Tue, Jul 28
Compare
Product Image of FS7-4SW, 1-1/4" Flow Switch w/ Stainless Steel Body, w/ NEMA 4X Enclosure
$1,354.11 each
In Stock
Get 2 by Mon, Jul 27
In Stock
Get 2 by Mon, Jul 27
Compare
Product Image of 1800, 1801, 2650, and 2651 Series Field Repair Kit, 0.5 GPM
$28.00 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Low Cost Timer Controller (6 Channels, DC)
Low Cost Timer Controller (6 Channels, DC)
SKU: DCT506ADC
Dwyer
SKU: DCT506ADC
Brand: Dwyer
$247.66 each
In Stock
Get 1 by Tue, Jul 28
In Stock
Get 1 by Tue, Jul 28
Compare
Product Image of 1" FS-204W Liquid - Wet Paddle-Type Flow Switch
$663.10 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Flotect Stainless Steel Explosion-Proof SPDT Liquid Level Switch, Spherical Side Wall Mount
$611.74 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
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 Tue, Jul 28
In Stock
Get 1 by Tue, Jul 28
Compare
Product Image of Timer Controller (10 Channels)
Timer Controller (10 Channels)
SKU: DCT610
Dwyer
SKU: DCT610
Brand: Dwyer
$284.28 each
Out of Stock
Get it by Fri, Aug 7 - Fri, Aug 14
Out of Stock
Get it by Fri, Aug 7 - Fri, Aug 14
Compare
Product Image of 2650 Series 1" Slip Socket PVC Shuttle Flow Switch Liquid/Water/Oil, 0.5 GPM Increasing Flow, No Conduit Connector
$113.40 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS5-S-1, 1" Flow Switch w/ Stainless Steel body
$1,420.78 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of 1" Brass Flow Switch NEMA4 w/ Flexible Paddles (Double Switch)
$374.61 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
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
In Stock
Get 1 by Tue, Jul 28
In Stock
Get 1 by Tue, Jul 28
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, Jul 24
In Stock
Get 1 by Tomorrow, Jul 24
Compare
Product Image of 1/8" MNPT Vertical Level Switch, All Stainless Steel
$77.13 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS4-15RP, Reinforced Stainless Steel Paddle Kit w/ 1" & 6" Paddles
$24.00 each
In Stock
Get 1 by Mon, Jul 27
In Stock
Get 1 by Mon, Jul 27
Compare
Product Image of FS4-3COV, Replacement Cover for Flow Switch
$23.87 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Vane Operated Flow Switch w/ Weatherproof Enclosure
$168.37 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of SPST Boiler Water Level Control, Close on Rise
$832.39 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Flotect Liquid Level Switch
Flotect Liquid Level Switch
SKU: L6EPB-SS3L-MT
Dwyer
SKU: L6EPB-SS3L-MT
Brand: Dwyer
$845.66 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of 1" Stainless Steel Flow Switch NEMA4 w/ Flexible Paddles (Small Turn Radius)
$662.37 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of GSKT-FS254, Gasket for FS254
$12.52 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Side Wall Mount Liquid Level Switch, 304 Stainless Steel Spherical Float
$436.57 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of S-2, Switch Cover Replacement
$23.62 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS7-31, Replacement Snap Switch for Flow Switch
$191.36 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS7-4EL, 1-1/4" Flow Switch w/ NEMA 7 & 9 enclosure, w/extended paddle & paddle arm
$751.93 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS7-VL-4R-4, Long Paddle Arm Kit
$265.09 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of AF3-122, Paddle Kit for AF3
$38.50 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS5-DS-1, 1" Flow Switch w/Stainless Steel body, 2 SPDT switches
$1,310.60 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
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
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Explosion-Proof Ultrasonic Level Transmitter (7.5 m Range, 2" MNPT, 1/2" NPT Conduit)
$2,031.63 each
In Stock
Get 2 by Tue, Jul 28
In Stock
Get 2 by Tue, Jul 28
Compare
Product Image of AF1-122, Paddle Kit for AF1 & AF1-J
$47.50 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of Low-Flow Stainless Steel Explosion-Proof Mini-Size Flow Switch, Lead Free
$554.57 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Compare
Product Image of FS7-4D, 1-1/4" Flow Switch w/2 SPDT
FS7-4D, 1-1/4" Flow Switch w/2 SPDT
SKU: 119750
McDonnell & Miller
SKU: 119750
$567.00 each
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Backorder
Get it by Fri, Aug 21 - Mon, Sep 21
Resources
FAQs, Manuals & Videos
Articles
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.