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Mcdonnell & Miller

Radiant Heat & Heating Supplies

Whether it's radiant heat, baseboard heating, hydronic heating, steam, electric or forced air heating, find all of the heating supplies to keep your home comfortable & warm.

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Application:	Replacement Part
Accessory For:	101A Series
	47 Series
	247 Series
	847 Series

Cartridge/Strainer Kit
for 101A, 47, 247, 847
Water Feeders

SKU: CTRD-101
Brand: Mcdonnell & Miller

In Stock!

8 Avail (Ships in 24-48 Hrs)

$94.25 / each

CTRD-101, Cartridge and Strainer Kit, Model CTRD-101

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Product Specifications
Application:	Replacement Part
Accessory For:	101A Series
	47 Series
	247 Series
	847 Series

CTRD-101, Cartridge & Strainer Kit, Model
CTRD-101

SKU: 310453
Brand: Mcdonnell & Miller

In Stock!

28 Avail (Ships in 24-48 Hrs)

$92.95 / each

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1" Flow Switch
w/ Gold Plated
Switch Contacts
- SKU: FS8-WG
- Brand: Mcdonnell & Miller
In Stock!
1 Avail (Ships in 24-48 Hrs)
$144.95 / each

Product Specifications
No Features Available

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Product Specifications
Application:	Steam Boilers
Switch:	Dual Precision Switches
Max Pressure:	20 psi (steam)
Type:	Float-Style
Insertion Length:	1-3/4"
Reset Type:	Automatic
Mount:	on 2-1/2" NPT Boiler Side Tappings
Electrical Ratings (AFL):	3.7 A @ 120 VAC
Electrical Ratings (ALR):	22.2 A @ 240 VAC

Float Type Low Water
Cut-off, 1-3/4" Insertion (Steam)

SKU: 369
Brand: Mcdonnell & Miller

In Stock!

4 Avail (Ships in 24-48 Hrs)

$189.95 / each

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Product Specifications
Application:	Hot Water Boilers
	Steam Boilers
Type:	Float-Style
Max Pressure:	100 psi
Max Vessel Pressure:	35 psi
Reset Type:	Automatic
Max Inlet Water Temp (F):	120°F
Width:	9"
Height:	10.375"

Mechanical Water Feeder

SKU: 51-S
Brand: Mcdonnell & Miller

Usually Ships 7-10 Days

$674.95 / each

Free Shipping

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Product Specifications
Application:	Replacement Part
Accessory For:	150S Series
Features:	Snap Switch

150S-HD, Head Assembly for 150 series
(Snap Switch)

SKU: 173003
Brand: Mcdonnell & Miller

In Stock!

54 Avail (Ships in 24-48 Hrs)

$391.49 / each

Free Shipping

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Product Specifications
Application:	Replacement Part
Accessory For:	PS-800 Series
	PS-850 Series

PA-800-RX2 Replacement Probe Remote

SKU: 354140
Brand: Mcdonnell & Miller

In Stock!

26 Avail (Ships in 24-48 Hrs)

$63.95 / each

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Product Specifications
Application:	Replacement Part
Accessory For:	RB-24E-A

UWH-RB-24A Universal Wiring Harness

SKU: 144681
Brand: Mcdonnell & Miller

In Stock!

30 Avail (Ships in 24-48 Hrs)

$20.95 / each

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Product Specifications
Application:	Boiler Receiver Tanks
Type:	Make-Up
Max Vessel Pressure:	35 psi
Max Inlet Water Temp (F):	120°F
Width:	17.4375"
Height:	11.8125"
Mount:	5-3/4" Bolt Circle
Bolt Hole Size:	7/16"
Connection Type:	NPT

21, Make-Up Water Feeder

SKU: 126400
Brand: Mcdonnell & Miller

In Stock!

6 Avail (Ships in 24-48 Hrs)

$374.55 / each

Free Shipping

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Product Specifications
Application:	Replacement Part
Accessory For:	21 Series

21-30, Float for 21

SKU: 311200
Brand: Mcdonnell & Miller

In Stock!

3 Avail (Ships in 24-48 Hrs)

$162.55 / each

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Product Specifications
Connection Size: 3/4"

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FS5-D-3/4, 3/4 Flow Switch w/ 2 SPDT switches
- SKU: 114763
- Brand: Mcdonnell & Miller
In Stock!
1 Avail (Ships in 24-48 Hrs)
$218.25 / each
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Product Specifications
Connection Size: 1"

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FS5-1, 1" Flow Switch
- SKU: 114780
- Brand: Mcdonnell & Miller
In Stock!
5 Avail (Ships in 24-48 Hrs)
$165.45 / each
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Product Specifications
Connection Size: 1"

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FS5-D-1, 1" Flow Switch w/ 2 SPDT switches
- SKU: 114783
- Brand: Mcdonnell & Miller
Usually Ships 7-10 Days
$218.25 / each
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Product Specifications
Connection Size: 1"

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FS4-3T1-1, 1" Flow Switch w/ NPT body
(High Flow Rate)
- SKU: 115100
- Brand: Mcdonnell & Miller
In Stock!
5 Avail (Ships in 24-48 Hrs)
$151.35 / each

Product Specifications
Connection Size:	3/4"

Product Specifications
Connection Size:	1"

Product Specifications
Connection Size:	1"

Product Specifications
Connection Size:	1"

FS4-3Z, 1" Flow Switch w/ ANSI terminal connections

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Product Specifications
Connection Size:	1"
Application:	Liquid Flow
Type:	General Purpose
Flow Rate:	6-166 FPM
Amperage:	7.4
	3.7
Voltage:	240v
	120v
Max PSI:	160 psi

FS4-3Z, 1" Flow Switch
w/ ANSI terminal connects

SKU: 114410
Brand: Mcdonnell & Miller

In Stock!

5 Avail (Ships in 24-48 Hrs)

$101.95 / each

69, Float Type Low Water Cut-off, 4-1/8" Insertion (Steam)

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Product Specifications
Application:	Steam Boilers
Switch:	Dual Precision Switches
Max Pressure:	20 psi (steam)
Type:	Float-Style
Insertion Length:	4-1/8"
Reset Type:	Automatic
Mount:	2-1/2" NPT Boiler Side Tappings
Electrical Ratings (AFL):	3.7 A @ 240 VAC
	7.4 A @ 120 VAC

69, Float Type LWCO
4-1/8" Insertion (Steam)

SKU: 153900
Brand: Mcdonnell & Miller

In Stock!

16 Avail (Ships in 24-48 Hrs)

$172.25 / each

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Product Specifications
Connection Size: 1"

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FS5-DS-1, 1" Flow Switch w/ Stainless Steel body
2 SPDT switches
- SKU: 114793
- Brand: Mcdonnell & Miller
Usually Ships 7-10 Days
$697.15 / each

Free Shipping

Product Specifications
Connection Size:	1"

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Product Specifications
Application:	Replacement Part
Accessory For:	25A Series
	27-W
Type:	Float-Style

421-30, Float Replacement Less Rod for 25A, 27W

SKU: 334100
Brand: Mcdonnell & Miller

In Stock!

7 Avail (Ships in 24-48 Hrs)

$122.45 / each

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Product Specifications
Application:	Steam Boilers
Switch:	Dual Precision Switches
Max Pressure:	20 psi (steam)
Type:	Float-Style
Reset Type:	Manual
Features:	Quick Hook-Up Fittings
Connection Type:	NPT
Electrical Ratings (AFL):	3.7 A @ 120 VAC
Electrical Ratings (ALR):	22.2 A @ 240 VAC

67-M, 67 Float Type
Low Water Cutoff
w/ manual reset (Steam)

SKU: 149700
Brand: Mcdonnell & Miller

In Stock!

26 Avail (Ships in 24-48 Hrs)

$247.95 / each

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Product Specifications
Application:	Replacement Part
Accessory For:	25A Series
	51 Series
	53 Series
	3155 Series
	51S Series
	221 Series

F-26, M35 Gasket for 221 25A, 51, 53, 3155

SKU: 304100
Brand: Mcdonnell & Miller

In Stock!

24 Avail (Ships in 24-48 Hrs)

$5.85 / each

1 - 20 of 334

More about Mcdonnell & Miller

For over 80 years, McDonnell & Miller has been an industry leader in the engineering and manufacturing of flow switches, low water cut-offs, water feeders, etc. Trust McDonnell & Miller for everything you need to move water.

Air Eliminators	Nipples
Air Valves	Pipe Insulation
Aquastats & Wells	Pressure Valves
Baseboard Heaters	Pumps & Flanges
Boilers	Radiant Heat
Expansions Tanks	Radiator Valves
Fittings	Relief Valves
Flow Controls Valves	Switching Relays
Flow Switches	Tekmar Controls
Gas Valves	Temperature Controllers
Gauges	Thermocouples
Heating Specialties	Thermostats
Kickspace Heaters	Transformers
Low Water Cutoffs	Water Feeders
Mixing Valves	Zone Valves & Controls

Access Doors	PEX Plumbing
Backflow Preventers	Plumbing Specialties
Chemicals & Compounds	Pumps
Expansion Tanks	Solder
Faucets & Sinks	Stops & Risers
Fittings	Tools
Flush Valves	Toilet Parts
Grease Traps	Tub & Shower Products
Outlet Boxes	Tubular Goods & P-Traps
Nipples	Valves
Pipe Hangers	Water Filters
Pipe Insulation	Water Heaters

Air Cleaners	HVAC Controls
Air Conditioners	Line Sets
AC Install Parts	Mini-Split Air Conditioners
Condensate Pumps	Replacement Parts
Dampers	Registers & Grilles
Dehumidifiers	Replacement Filters
Filter Driers	Thermostats
Flex Duct	Tools
Humidifiers	Ventilation Fans

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