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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PSE801-120 | 120v Probe Type Lwco For Steam 153827 Replaces PS801-120 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: PSE801-120
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MA259 | Quick Hook Up Fittings For 42A4764A 332800 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: MA259
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FS8-W | SPDT 1" General Purpose Flow Switch Nema 4X 120601 Replaces FS8-V | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS8-W
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FS5-1 | Flow Switch(low Flow Rate Sensitivity) 1" 114780 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS5-1
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FS4-3RP-T | General Purpose Liquid Flow Switch With Re-inforced Paddle 114639 Replaces FS4-3RP 114650 Has Manual Test Feature | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS4-3RP-T
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FS4-3 | Nema 1 SPDT General Purpose Liquid Flow Switch 1" Includes 123 & 6" Paddle 114400 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS4-3
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FS4-15SS | Stainless Steel Paddle Kit Includes A 1" 2" 3" & 6" Paddle 310451 Replaces FS4-37 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS4-15SS
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FS254 | SPDT 1" NPT. General Purpose Nema-4 Flow Switch Includes 1" 2" 3" & 6" Stainless Steel Paddles 120610 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS254
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FS251 | SPDT 1" NPT. General Purpose Liquid Flow Switch Includes 1" 2" 3" & 6" Stainless Steel Paddles 120611 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS251
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FS1-W | 1/2" In-line High Sensitivity Flow Switch W/nema-4X enclosure 113601 | MCDONNELL & MILLER (OBSOLETE)
Brand: MCDONNELL & MILLER
SKU: FS1-W
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FS1 | 1/2" In-line High Sensitivity Flow Switch 113200 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: FS1
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F-26 | Head Gasket For 22125a51 533155 304200 old # 304100 (m10) *** SOLD INDIVIDUALLY *** | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: F-26
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EA-157-S | Short Electrode For 157-RBP 354106 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: EA-157-S
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EA-157-L | Long Electrode For 157-RBP 354107 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: EA-157-L
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CO-11 | Sylphon Base Gasket For 42 63 new # 303600 old # 302500 (m5) *** SOLD INDIVIDUALLY *** | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: CO-11
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BA53-05 | 310441 New Style Bellows Assembly With Gasket For 53 Replaces 310483 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: BA53-05
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93-HDLS | 93 & 193 Head Less Switch 162402 | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: 93-HDLS
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847-26 | Head Gasket 21847851 335400 (m5) *** SOLD INDIVIDUALLY *** | MCDONNELL & MILLER
Brand: MCDONNELL & MILLER
SKU: 847-26
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
- 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
- Residential/Commercial/Industrial Low or High Pressure Boiler Applications
- 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
Details
End Connection
Material
Part Number
- 47
- 51
- 101A-24
- 129802
- 132900
- 133400
- 133900
- 135100
- 135200
- 135300
- 135500
- 136200
- 143200
- 143700
- 144676
- 149400
- 149500
- 155400
- 162400
- 163100
- 163500
- 163600
- 164100
- 164525
- 165500
- 165800
- 166500
- 166700
- 166701
- 167200
- 169400
- 169550
- 169560
- 171900
- 171907
- 172819
- 173702
- 176212
- 176236
- 178402
- 178802
- 247
- 247-2
- 25A
- 47-2
- 51-2
- 51S-2
- 53-2
- 551S
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 Replacement
- Cutoff with Manual Reset
- Direct Acting Liquid Level 3-15PSI Output
- Dirt Pocket 47-171 for 47/247 Series
- Electric
- Electric Replacement
- Electric with Manual Reset
- Electronic Manual Reset
- 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
- FS4-3D with 2 SPDT Switches
- FS4-3S with SPDT Body Stainless Steel
- FS4-3T1-3 High Flow SPDT
- FS4-3T3-1 Low Flow SPDT
- FS4-3T3-4 Low Flow SPDT
- FS6-W-1 with NEMA 4X Enclosure 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 847/851 Model 37A-130
- 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
- For Water Feeder 53-HD
- 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 FS7-28
- Kit Model FS7-4W
- Large Model SA47-4
- Less Quick Hook Up Fittings
- Less Switch Steam 93-HDLS
- Liquid
- Liquid SPDT
- Liquid with Test Feature
- Long Barrel
- Long EA-157L for Series 157S-RBP
- Low Velocity Single Pole Double Throw
- 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 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
- Model P-1/3-SS
- Output For Series PFC G-PFC-O
- 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 FS4-33
- Replacement For 101A Series
- Replacement Harness for RB-24E-L
- Replacement Remote
- Replacement for 21 Series
- Replacement for 25A/27W
- 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 51-S-2-HD Low Water Cut Off
- 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
- Single Pole Double Throw with NEMA 7/9 Enclosure
- 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
- Spring Pressure Control Model SPS-30
- 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 FDR 51S-HD
- 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 Control Board Harness Model RB-24E-S
- With Corrosion Coating Single Pole Double Throw
- With Extended Barrel U Probe
- 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 FTL-53-05
- With Gasket Model SA53-6
- With Gasket Model SA64-30
- With Gasket SA-63-30
- With Gasket for Model 51S-114
- 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 194-7B with Manual Reset
- With Pump Controller 194-A with 7B Switch
- With Pump Controller 2 Single Pole Double Throw Switches
- With Pump Controller 2 Single Pole Single Throw Switches
- With Pump Controller 94 with 5 Switch SPDT
- With Pump Controller 94 with 7B 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 SA47-101-102
- With Strainer SA51-101-102
- With Vent Damper Harness Model RB-24E-A
- Y for 42A/47/64A/67
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
- RS Series 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 47; 247; 847
- 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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