mcdonnell miller
McDonnell Miller, a trusted name in boiler controls and flow switches, offers a comprehensive collection of products designed for efficiency and reliability. Explore our selection and find the perfect fit for your needs.
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129302 | Pump Controller 42S Combo Low Water Cut Off with Auto Reset SPST 120/240 Volt | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 129302
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127200 | Level Control 27-W Liquid 3/4 Inch Brass | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 127200
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127100 | Head Mechanism 25A-HD for Water Feeder 25-A Series | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 127100
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126400 | Water Feeder 21 Make Up Proportional Feed Action | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 126400
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123450 | Flow Switch AF3-D with 2 Single Pole Double Throw Switches | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 123450
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123400 | Flow Switch AF3 Medium Velocity Single Pole Double Throw | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 123400
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123010 | Flow Switch AFE1-1 with NEMA 7/9 Enclosure Single Pole Double Throw | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 123010
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122920 | Flow Switch AF1-J with Corrosion Coating Single Pole Double Throw | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 122920
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122800 | Flow Switch AF1 Single Pole Double Throw | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 122800
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120611 | Flow Switch FS-251 General Purpose SPDT with NEMA-1 Enclosure 1 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120611
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120610 | Flow Switch FS254 General Purpose SPDT with NEMA-4 Enclosure 1 Inch | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120610
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120601 | Flow Switch FS8-W General Purpose SPDT with NEMA-4 Enclosure 1 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120601
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120191 | Flow Switch FS7-4SW Stainless Steel Body NEMA 4X Enclosure Single Pole Double Throw 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120191
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120175 | Flow Switch FS7-4SE Stainless SPDT with NEMA 7-9 Enclosure 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120175
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120160 | Flow Switch FS7-4S with Stainless Steel Body Single Pole Double Throw 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120160
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120150 | Flow Switch FS7-4EL with Extended Paddle/Arm Single Pole Double Throw 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 120150
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119900 | Flow Switch FS7-4L with Extended Paddle/Arm Single Pole Double Throw 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 119900
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119750 | Flow Switch FS7-4D with 2 SPDT 1-1/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 119750
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115600 | Flow Switch FS6-1 High Sensitivity Liquid SPDT 1 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 115600
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115400 | Flow Switch FS6-3/4 High Sensitivity SPDT 3/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 115400
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115100 | Flow Switch FS4-3T1-1 Single Pole Double Throw 1 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 115100
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115000 | Flow Switch FS4-3T3-4 Low Flow SPDT 3/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 115000
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114800 | Flow Switch FS4-3T1-3 High Flow SPDT 3/4 Inch NPT | Mcdonnell Miller
Brand: Mcdonnell Miller
SKU: 114800
Application
- 101A; 47; 247; 847 Water Feeders
- 25-A Series Make-Up Water Feeder
- 42 and 42S Series Low Water Cut-Offs/Pump Controller
- 51; 851 Water Feeder
- Boiler Control
- Commercial/Industrial Low or High Pressure Boilers
- Commercial/Industrial Low or High Pressure Steam Boilers
- Electronic for Hot Water and Steam Boiler
- Low Water Cut Offs Water Feeder
- Low Water Cut Offs; Steam Boilers
- Primary Low Water Fuel Cut Off Protection and Pump Control for Commercial and Industrial Steam Boiler
- Protection Against High Water Condition in Steam Boilers and Other Water Level Applications
- Residential/Commercial Boilers with Steaming Capacity
- Residential/Commercial Industrial Low and Medium Pressure Steam Boilers with Separate Water Column
- Residential/Commercial Low Pressure Steam Boiler
- Residential/Commercial/Industrial Boiler with Steaming Capacity
- Series 247 and 247-2 Combination Low Water Cut-Offs/Pump Controllers
- Series 63 Low Water Cut-Offs
- Series FS4-3 and FS8-W General Purpose Liquid Flow Switches
- Tanks and Hydronic Heating Systems
- Water Feeders
Collection
End Connection
Material
Part Number
Pressure
Product Type
- 150S-HD with Manual Reset and Maximum Differential
- 158-S-HD with Manual Reset
- 2 Level High Pressure
- 51-2HD for Mechanical Water Feeder with Number 2 Switch Low Water Cut Off
- 69 with 1-3/16IN Insertion Length
- 851-S Make-Up with Extended Float and Rod Assembly
- Air
- Assembly CTRD-101
- Assembly CTRD-51
- Assembly For RS Series
- Assembly G-3-SS
- Assembly for 93/193/194 Control
- Auto Reset
- Ball Type for 47/247/67/70B Series
- Basket SA101-38
- CO-106 Screw and Pin
- Cast Iron Sensor Chamber with Probes
- Combination Pump Controller
- Combo Low Water Cut Off with Auto Reset SPST
- Combo Low Water Cut Off with Float Manual Reset SPST/SPDT
- Combo Low Water Cut Off with Maximum Differential SPST SPDT
- Combo Low Water Cut Off with Number 5 Switch
- Combo Low Water Cut Off with Quick Hook Up Fitting SPST
- Cover 4 Hole for RS-1 BR-1 Remote Sensor
- Cover for VFS VFC Gasket-PFC Series
- Cutoff with Manual Reset
- Direct Acting Liquid Level 3-15PSI Output
- Dirt Pocket 47-171 for 47/247 Series
- Electric
- Electric Replacement
- Electronic Manual Reset Probe
- Electronic with Auto Reset
- Electronic with Burner Control Harness
- Electronic with Manual Reset
- FLT-51-05 for 51 Water Feeder
- FS4-15
- FS4-3S with SPDT Body Stainless Steel
- FS4-3T1-3 High Flow SPDT
- FS4-3T3-4 Low Flow SPDT
- FS7-4D with 2 SPDT
- FS7-4SE Stainless SPDT with NEMA 7-9 Enclosure
- Fitting Lower for 42A/47/64A/67 Series
- Fitting Upper for 47/64/42/42S Series
- Fitting for 67 Series
- Float Arm 21-109 Model
- Float Type
- Float Type 3-18IN Insertion
- Float Type Auto Reset Number 2 Switch
- Float Type Manual Reset Number 2 Switch
- Float Type with 1-3/4IN Insertion
- Float Type with 2-1/4IN Insertion Length
- Float for Pneumatic Actuated Series PFC
- For 150 Series Snap Switch
- For 21 Series
- For 61/64/67/69/70/764/767
- For 64 Series
- For 69+ Series Model SA69-104
- For Combo Low Water Cut Off/Pump Controller With Manual Reset
- For Float Type Combo Low Water Cut Off/Pump Controller with Manual Reset
- For Low Water Cut Off 63 Series
- For Low Water Cut Off 64 Series
- For Low Water Cut Off 750/750-MT-120/PS800/PS801/PS850/PS851 Series
- For Mechanical Water Feeder 51 Series
- For RB-24E-S
- For Series 21 Make-Up Water Feeders
- For Series 51/52-2 Bellows Water Feeder BA-51-05
- For Series 851-S Make-Up Water Feeders
- For Series BA-551-05 Bellows
- For TC-4 Test-N-Check Valve
- For Water Feeder 25-A Series
- General Purpose Liquid SPDT
- General Purpose SPDT
- General Purpose SPDT with NEMA-1 Enclosure
- General Purpose SPDT with NEMA-4 Enclosure
- Ground
- High Pressure Model PA-750-HP
- High Sensitivity Liquid SPDT
- High Sensitivity SPDT
- High Sensitivity Single Pole Double Throw
- Insert for Low Water Cut Off 67 Series
- Junction F/Series 150-150S Low Water Cut Off Pump Controller
- Kit Model FS7-4W
- Large Model SA47-4
- Less Quick Hook Up Fittings
- Less Switch Steam 93-HDLS
- Liquid
- Long Barrel
- Long EA-157L for Series 157S-RBP
- Low Water Cut Off Controller Less Switch
- Low Water Cut Off Float Type Snap Switch SPST/SPDT
- Low Water Cut Off Float with Maximum Differential SPST/SPDT
- Low Water Cut Off Less Quick Hook Up Fittings
- Low Water Cut Off Number 5 Switch with Water Column
- Low Water Cut Off Proportional 7B with Manual Reset
- Low Water Cut Off Snap Acting Switch
- Low Water Cut-off
- Lower Test Model TC-L
- Main Valve 2200-2300
- Make Up
- Make Up Proportional Feed Action
- Make-Up for Model 847
- Manual Reset
- Manual Reset with Barrel Probe
- Manual Reset with Short Probe
- Manual Reset with Standard Probe
- Mechanical
- Mechanical Dual Switch
- Mechanical Less Quick Hook Up Fittings
- Medium Velocity Single Pole Double Throw
- Model 250-1 1.437M BTU
- Model 260-1
- Model BA-53-05
- Paddle Kit with 1IN and 6IN Paddles
- Potentiometer Automatic Reset
- Probe Style Auto Reset
- Probe for 4 Level Remote Sensor Model RS-4-BR-1
- Quick Hook Up
- Quick Hook Up Auto Reset Float Style
- Quick Hook Up Lever Operated
- RS-1-LP Low Pressure Sensor
- Remote High
- Replacement For 101A Series
- Replacement Harness for RB-24E-L
- Replacement Remote
- Replacement for 42S
- Replacement for 67-G
- Replacement for 93/193 Series Combination Low Water Cut Off Pump Controller
- Replacement for B-24E-B
- Replacement for Low Water Cut Off
- Replacement for Mechanical Water Feeder
- Replacement for Model 63BM/63M Float Type Low Water Cut Off
- Replacement for Model 93/193 Low Water Cut Off
- Replacement with 7B Switch for 94/194 Series Control
- Replacement with Manual Reset
- Reverse Acting Liquid Level 3-15PSI Output
- Reverse Acting Model SWA-PFC-R
- SA150-106R Replacement
- SA150-11 for Series 150/157 with Gasket
- SA159-17
- SA21-6
- SA25-5
- SA25A-15 with Valve Disc
- SA25A-6
- SA27T-75 Diaphragm
- SA37-30
- SA47-104 Replacement
- SA51-9
- SA51-9R
- SA51S-6
- SA63-5
- SA67-2
- Short EA-157S for Series 157S-RBP
- Short PA-Rb-122
- Single Level Remote High Pressure
- Single Pole Double Throw
- Slide Kit Model 7B-1R for 7B Switch
- Snap Action for 150S/157S Model SWA150S-M
- Snap Action for 42S Model SWA42S
- Snap Action for Model SWA150S-MD
- Snap Assembly Replacement
- Snap Assembly for SW-FS250
- Snap FS7-31
- Spring Loaded
- Stainless Steel Body NEMA 4X Enclosure Single Pole Double Throw
- Strainer for WF2U and WFE Series
- Supply for Pneumatic Actuated G-PFC-S
- Switch Replacement
- Teflon Coated
- Test-N- Check
- Universal for Hot Water Boilers with Vent Damper
- Upper SA66-35
- Upper Test Vacuum Breaker with Gasket Model TC-U
- Water Feeder Make-Up for 551S-HD
- With 2 Single Pole Double Throw Switches
- With 4-1/8IN Insertion Length
- With Auto Reset
- With Barrel Probe
- With Blow Down Auto Reset
- With Burner Control Harness
- With Corrosion Coating Single Pole Double Throw
- With Extended Paddle/Arm Single Pole Double Throw
- With Extension Barrel Model PSE-802-24
- With Fitting
- With Float Block
- With Float Block 63B
- With Gasket Model SA53-6
- With Gasket Model SA64-30
- With Gasket SA-63-30
- With Low Water Cut Off #2 Switch
- With Low Water Cut Off #2 Switch Manual Reset
- With Low Water Cut-off Mechanical
- With Manual Reset
- With Manual Reset Quick Hook Up
- With Millivolt Switch Length 1-3/4IN Insertion Length
- With NEMA 7/9 Enclosure Single Pole Double Throw
- With Pump Controller 150S-B with Manual Reset
- With Pump Controller 157S SPDT with Water Column
- With Pump Controller 157S with Manual Reset SPDT
- With Pump Controller 157S-R SPDT with Alternate Tapings
- With Pump Controller 157S-RBP-MD SPDT with 2 Integral Conductance Probes
- With Pump Controller 157S-RL Float Type Combo SPST/SPDT Auto Reset
- With Pump Controller 193 with 7B Switch Steam
- With Pump Controller 193-A with 7B Switch Steam
- With Pump Controller 193-B with 7B Switch Steam
- With Pump Controller 194-A with 7B Switch
- With Pump Controller 94 with 5 Switch SPDT
- With Pump Controller Alternate Tapping
- With Pump Controller Glass Connector
- With Pump Controller Manual Reset
- With Pump Controller Model 93-7B SPDT
- With Pump Controller Model 93-M SPDT Steam
- With Pump Controller Series 7B Switch
- With Pump Controller and Float Block
- With Quick Hook Up Fittings
- With Remote Sensor RX2 Probe
- With Stainless Steel Body Single Pole Double Throw
- With Standard Probe
- With Strainer SA51-101-102
- With Vent Damper Harness Model RB-24E-A
Size
Temperature
Used on
- 101-A Series Electrical Water Feeder and 551-S Series Make-Up Water Feeder
- 21; 25-A and 221 Series Make-Up Water Feeder
- 25-A Series Make-Up Water Feeder
- 64A; 47; 47-2 Controls
- 750B-C3/750B-C4 Series
- Actuation Control
- Air Flow
- Boiler
- Boiler Receiver Tanks
- Commercial and Industrial Liquid Level Open Tank Applications
- Hot Water/Steam Boilers
- Liquid Flow
- Low Pressure Steam and Hot Water Boilers
- Low Pressure Steam/Hot Water Boilers
- MA-159/MA-259 Quick Hook-up Fitting
- Multilevel Control
- PS-800/850 Series
- PS-801-U-120/PS-802-U-24 Series
- RS Sensors
- Series 150E/157E
- Series 21 and 221 Make-Up Water Feeders
- Series 247; 247-2; 47 and 47-2 Combination Low Water Cut-Offs/Pump Controllers
- Series 25A
- Series 51-S and 51-S-2 Combination Mechanical Water Feeder/Low Water Cut-Offs and Series 851-S Make-Up Water Feeders
- Series 51; 851
- Series 61/64/67/69/70
- Series 61; 67; 69 and 767 Low Water Cut-Off
- Series 63 Low Water Cut-Offs and Series 47; 47-2; 247; 247-2; 51; 51-2; 51-S; 51-S-2; 53 and 53-2 Combination Mechanical Water Feeder/Low Water Cut-Offs
- Series 67 Low Water Cut-Offs
- Series 750B Remote Mount Control Modules
- Series 93; 193; 94 and 194 Combination Low Water Cut-Offs/Pump Controllers
- Steam Boilers
- Steam/Hot Water Boilers with Cold Water Feed
- Water Boiler
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