Robinair 17800C Multi-Refrigerant Recover, Recycle, Recharge Machine — $10,549.70Enerpac SC10HTB 10 Ton, Four Hydraulic Cylinders and Hand Pump Toolbox Set — $6,826.67Powerex SLAE05EHP 5 HP High Pressure Oil-Less Scroll Air Compressor Bare Pump, 145 PSI — $6,083.84Milwaukee 2922-22M M18 FORCE LOGIC Press Tool Kit with ONE-KEY, 1/4 in - 7/8 in Streamline ACR Jaws — $4,605.02Husqvarna K1270 Rail 16" Rail Power Cutter — $3,818.08Detex AO19-1 Low Energy Automatic Door Operator for Single Doors, Right Hand Push — $3,745.56Durham Super Duty Bin Cabinet, 48 in W x 24 in D x 78 in H, 84 Blue Bins, 2 Adjustable Shelves, 6 Door Shelves, 12 Gauge Steel, Gray — $2,351.02Pace 8007-0597 MBT360 Multi-Channel Soldering and Rework Station w/ 3 Handpieces, 115V — $2,271.35Billy Goat KV601SP 27" Self-Propelled Outdoor Litter Vacuum, 190cc — $1,906.10Baldor EHM3311T Super-E HVAC Motor, 7.5 HP, 1770 RPM, 213T, OPSB, 230/460V 3-Phase — $1,397.88JB Industries DV-285N Platinum 10 CFM Vacuum Pump, 1/2 HP, 115V — $1,181.45Von Duprin 958003-00 Quiet Electric Latch Retraction Retrofit Kit, 3 ft — $995.63Baldor EM3558T 2 HP 1755 RPM 145T TEFC Motor, 208-230/460V, 3-Phase — $922.87Vestil LAD-7-21-P-EZ Steel Rolling Warehouse Ladder, 7 Step, Perforated, 50 Degree, 21 in Deep Top Step — $908.46Hubbell HBL4100P9W IEC Pin and Sleeve Plug, 3-Pole 4-Wire, 100A, 250V, Watertight, Blue — $872.38Lexmark MS821n Monochrome Laser Printer, 55 ppm — $843.01Barksdale 9021-MC-A Shear-Seal Manual Directional Control Valve, 1/4 in — $787.66Rite-Hite 504AR Holdown-Ramp Control w/5016 Ratchet Bar & Patented Auto Release — $741.85Rubbermaid FG9W7300BLA Mega Brute 120 Gallon Black Executive Series Mobile Waste Collector — $723.24Walter 30A606 Straight-Mate 6" 110V Straight Grinder — $706.57Buckhorn BH4845342010000 48 x 45 x 34 in. Collapsible Bulk Shipping Container, Black, 2500 lb — $694.81Louisville Ladder FE4228HD 28 ft. Fiberglass Extension Ladder, ANSI Type IAA, 375 lbs. Load Capacity — $694.82Alarm Lock Trilogy DL2700IC26D T2 Digital Keypad Lever Lock, SFIC Prep, Satin Chrome (Less Core) — $681.73Yale AU5405LN-626 5400LN Series Grade 1 Storeroom Cylindrical Lever Lock, Augusta Lever, Satin Chrome — $548.80APC RBC55 Replacement Battery Cartridge #55 — $495.83Yellow Jacket 46013 BRUTE II 4-Valve Test and Charging Manifold with 60 in Hoses — $481.83Odyssey ODX-AGM24M Extreme Series 12V Group 24 Marine Dual Purpose AGM Battery, 840 CCA — $465.49Amano BX-1500 Electronic Time Recorder — $440.99DEWALT DCN930B 20V MAX XR Brushless 30-Degree Paper Tape Framing Nailer (Bare Tool) — $391.02FLIR TG165-X MSX Thermal Imaging Camera, 80 x 60, -25°C to 300°C, with Bullseye Laser — $391.02Fellowes Powershred 99Ci 18-Sheet Cross-Cut Paper Shredder, P-4, 100% Jam Proof — $382.19Bard S8105-039 CW Condenser Fan Motor, 1/3 HP, 208-230V, 825 RPM — $341.81Dayton 3YU59 1/2 HP Submersible Sump Pump, 1-1/4 in MNPT, 120V AC, Vertical Float — $297.86Berko SRA Series SRA2027DS Commercial Fan-Forced Small Wall Heater, 2000/1000W 277/240V — $294.12ESAB Dual Shield 710X Gas-Shielded Flux-Cored Welding Wire, .045 in x 33 lb Spool — $279.30Bendix K021557 SR-7 Spring Brake Modulating Valve — $278.50Dayco 80062 Fuel Line Hose, 5/16" ID x 250 ft — $266.30GRK R4 Multi-Purpose Framing Screw #9 x 3-1/8 in. (00105) — $265.57Maxx Ice 1858904400 Water Pump for MIM250/450 Ice Machines — $262.17OTC 7947 8-Way Slide Hammer Puller Set with Storage Case — $261.66DEWALT DCE560B 20V MAX Cordless Adhesive Gun, 10 oz / 300 ml (Tool Only) — $259.70WEG .7536OS3EJPR56C-S Jet Pump Motor, 0.75 HP, 3600 RPM, 56C Frame, ODP, 3-Phase, 208-230/460V — $249.27Ingersoll Rand 1099XPA 1/2 in Air Ratchet Wrench, 76 ft-lb, 220 RPM — $248.82BN Products-USA BNR6500 1800W Hand-Held Power Mixer, 120V, 2-Speed — $243.04NEXIQ Technologies MPS493033 3-Pin Deutsch 2-Pin Cummins Adapter — $226.86XR 20V MAX Brushless Cordless 3 in. Cut-Off Tool Kit — $223.06Square D 8910DPA53V06 Definite Purpose Contactor, 3 Pole, 50A, 480VAC Coil — $219.41RIDGID 18383 S36 Bolt Cutter Head Assembly, Center Cut — $195.953M Protecta Rebel 3100513 11 ft Web Self-Retracting Lifeline (SRL) with Steel Snap Hook and Anchorage Carabiner — $193.05Honeywell BZE6-2RN18 MICRO SWITCH Medium-Duty Enclosed Limit Switch, Wobble Coil Spring, SPDT, 15A, IP66 — $192.13Bergen Industries GL100182LED 100 ft LED Temporary Construction String Light, 18/2 AWG, 15A, 16,000 Lumens, Yellow — $181.29Norton 8301-689 Architectural Door Closer, Aluminum (689), Sizes 1-6, Tri-Style — $173.81AC Works L1530PR-025 SOOW 10/4 NEMA L15-30 30A 3-Phase 250V Industrial Rubber Extension Cord, 25 ft — $165.61UEI DM525 True RMS Wireless Digital Multimeter, 1000V AC/DC — $159.233M 7000126728 Adflo Leather Belt 15-0099-16, 1 EA/Case — $155.84Honeywell L6006C1018 Aquastat Controller - High or Low Limit / Circulator Control, Strap-On, 65-200 F — $153.38LOCTITE 271 Red Threadlocker, 250 ml Bottle — $147.14DeWalt DW099S Tool Connect 100 ft. Laser Distance Measurer — $143.6216 Pc. 72-Tooth 12 Point Ratcheting Combination Metric Wrench Set — $141.70CyberPower EC850LCD Ecologic UPS System, 850VA/510W, 12 Outlets, LCD — $129.31Blue Demon ER308L-023-10 Stainless Steel MIG Welding Wire, .023 in, 10 lb Spool — $127.88Buyers Products RM62000 6-Ton Receiver Mount Combination Hitch with 2 in Ball — $126.41ABB AF09ZB-30-10-21 Railway Contactor, 3-Pole, 1NO Auxiliary, Coil 24-60V AC / 20-60V DC, Screw Terminals — $112.03Milwaukee 48-73-1313 BOLT Orange Safety Helmet, Type 2, Class E — $107.77Honda 06424-ZS9-000AH EU3000is Generator 4-Wheel Kit with Locking Front Swivel Casters — $103.58Genuine Mopar Serpentine Belt for 2003-2012 Dodge Ram Cummins 5.9L/6.7L (Mopar 53041138AE) — $88.18Parker E-Z Mate EZ-501-8FP Pneumatic Push-to-Connect Coupler, 1/2 in Female NPT — $70.66Robinair 17800C Multi-Refrigerant Recover, Recycle, Recharge Machine — $10,549.70Enerpac SC10HTB 10 Ton, Four Hydraulic Cylinders and Hand Pump Toolbox Set — $6,826.67Powerex SLAE05EHP 5 HP High Pressure Oil-Less Scroll Air Compressor Bare Pump, 145 PSI — $6,083.84Milwaukee 2922-22M M18 FORCE LOGIC Press Tool Kit with ONE-KEY, 1/4 in - 7/8 in Streamline ACR Jaws — $4,605.02Husqvarna K1270 Rail 16" Rail Power Cutter — $3,818.08Detex AO19-1 Low Energy Automatic Door Operator for Single Doors, Right Hand Push — $3,745.56Durham Super Duty Bin Cabinet, 48 in W x 24 in D x 78 in H, 84 Blue Bins, 2 Adjustable Shelves, 6 Door Shelves, 12 Gauge Steel, Gray — $2,351.02Pace 8007-0597 MBT360 Multi-Channel Soldering and Rework Station w/ 3 Handpieces, 115V — $2,271.35Billy Goat KV601SP 27" Self-Propelled Outdoor Litter Vacuum, 190cc — $1,906.10Baldor EHM3311T Super-E HVAC Motor, 7.5 HP, 1770 RPM, 213T, OPSB, 230/460V 3-Phase — $1,397.88JB Industries DV-285N Platinum 10 CFM Vacuum Pump, 1/2 HP, 115V — $1,181.45Von Duprin 958003-00 Quiet Electric Latch Retraction Retrofit Kit, 3 ft — $995.63Baldor EM3558T 2 HP 1755 RPM 145T TEFC Motor, 208-230/460V, 3-Phase — $922.87Vestil LAD-7-21-P-EZ Steel Rolling Warehouse Ladder, 7 Step, Perforated, 50 Degree, 21 in Deep Top Step — $908.46Hubbell HBL4100P9W IEC Pin and Sleeve Plug, 3-Pole 4-Wire, 100A, 250V, Watertight, Blue — $872.38Lexmark MS821n Monochrome Laser Printer, 55 ppm — $843.01Barksdale 9021-MC-A Shear-Seal Manual Directional Control Valve, 1/4 in — $787.66Rite-Hite 504AR Holdown-Ramp Control w/5016 Ratchet Bar & Patented Auto Release — $741.85Rubbermaid FG9W7300BLA Mega Brute 120 Gallon Black Executive Series Mobile Waste Collector — $723.24Walter 30A606 Straight-Mate 6" 110V Straight Grinder — $706.57Buckhorn BH4845342010000 48 x 45 x 34 in. Collapsible Bulk Shipping Container, Black, 2500 lb — $694.81Louisville Ladder FE4228HD 28 ft. Fiberglass Extension Ladder, ANSI Type IAA, 375 lbs. Load Capacity — $694.82Alarm Lock Trilogy DL2700IC26D T2 Digital Keypad Lever Lock, SFIC Prep, Satin Chrome (Less Core) — $681.73Yale AU5405LN-626 5400LN Series Grade 1 Storeroom Cylindrical Lever Lock, Augusta Lever, Satin Chrome — $548.80APC RBC55 Replacement Battery Cartridge #55 — $495.83Yellow Jacket 46013 BRUTE II 4-Valve Test and Charging Manifold with 60 in Hoses — $481.83Odyssey ODX-AGM24M Extreme Series 12V Group 24 Marine Dual Purpose AGM Battery, 840 CCA — $465.49Amano BX-1500 Electronic Time Recorder — $440.99DEWALT DCN930B 20V MAX XR Brushless 30-Degree Paper Tape Framing Nailer (Bare Tool) — $391.02FLIR TG165-X MSX Thermal Imaging Camera, 80 x 60, -25°C to 300°C, with Bullseye Laser — $391.02Fellowes Powershred 99Ci 18-Sheet Cross-Cut Paper Shredder, P-4, 100% Jam Proof — $382.19Bard S8105-039 CW Condenser Fan Motor, 1/3 HP, 208-230V, 825 RPM — $341.81Dayton 3YU59 1/2 HP Submersible Sump Pump, 1-1/4 in MNPT, 120V AC, Vertical Float — $297.86Berko SRA Series SRA2027DS Commercial Fan-Forced Small Wall Heater, 2000/1000W 277/240V — $294.12ESAB Dual Shield 710X Gas-Shielded Flux-Cored Welding Wire, .045 in x 33 lb Spool — $279.30Bendix K021557 SR-7 Spring Brake Modulating Valve — $278.50Dayco 80062 Fuel Line Hose, 5/16" ID x 250 ft — $266.30GRK R4 Multi-Purpose Framing Screw #9 x 3-1/8 in. (00105) — $265.57Maxx Ice 1858904400 Water Pump for MIM250/450 Ice Machines — $262.17OTC 7947 8-Way Slide Hammer Puller Set with Storage Case — $261.66DEWALT DCE560B 20V MAX Cordless Adhesive Gun, 10 oz / 300 ml (Tool Only) — $259.70WEG .7536OS3EJPR56C-S Jet Pump Motor, 0.75 HP, 3600 RPM, 56C Frame, ODP, 3-Phase, 208-230/460V — $249.27Ingersoll Rand 1099XPA 1/2 in Air Ratchet Wrench, 76 ft-lb, 220 RPM — $248.82BN Products-USA BNR6500 1800W Hand-Held Power Mixer, 120V, 2-Speed — $243.04NEXIQ Technologies MPS493033 3-Pin Deutsch 2-Pin Cummins Adapter — $226.86XR 20V MAX Brushless Cordless 3 in. Cut-Off Tool Kit — $223.06Square D 8910DPA53V06 Definite Purpose Contactor, 3 Pole, 50A, 480VAC Coil — $219.41RIDGID 18383 S36 Bolt Cutter Head Assembly, Center Cut — $195.953M Protecta Rebel 3100513 11 ft Web Self-Retracting Lifeline (SRL) with Steel Snap Hook and Anchorage Carabiner — $193.05Honeywell BZE6-2RN18 MICRO SWITCH Medium-Duty Enclosed Limit Switch, Wobble Coil Spring, SPDT, 15A, IP66 — $192.13Bergen Industries GL100182LED 100 ft LED Temporary Construction String Light, 18/2 AWG, 15A, 16,000 Lumens, Yellow — $181.29Norton 8301-689 Architectural Door Closer, Aluminum (689), Sizes 1-6, Tri-Style — $173.81AC Works L1530PR-025 SOOW 10/4 NEMA L15-30 30A 3-Phase 250V Industrial Rubber Extension Cord, 25 ft — $165.61UEI DM525 True RMS Wireless Digital Multimeter, 1000V AC/DC — $159.233M 7000126728 Adflo Leather Belt 15-0099-16, 1 EA/Case — $155.84Honeywell L6006C1018 Aquastat Controller - High or Low Limit / Circulator Control, Strap-On, 65-200 F — $153.38LOCTITE 271 Red Threadlocker, 250 ml Bottle — $147.14DeWalt DW099S Tool Connect 100 ft. Laser Distance Measurer — $143.6216 Pc. 72-Tooth 12 Point Ratcheting Combination Metric Wrench Set — $141.70CyberPower EC850LCD Ecologic UPS System, 850VA/510W, 12 Outlets, LCD — $129.31Blue Demon ER308L-023-10 Stainless Steel MIG Welding Wire, .023 in, 10 lb Spool — $127.88Buyers Products RM62000 6-Ton Receiver Mount Combination Hitch with 2 in Ball — $126.41ABB AF09ZB-30-10-21 Railway Contactor, 3-Pole, 1NO Auxiliary, Coil 24-60V AC / 20-60V DC, Screw Terminals — $112.03Milwaukee 48-73-1313 BOLT Orange Safety Helmet, Type 2, Class E — $107.77Honda 06424-ZS9-000AH EU3000is Generator 4-Wheel Kit with Locking Front Swivel Casters — $103.58Genuine Mopar Serpentine Belt for 2003-2012 Dodge Ram Cummins 5.9L/6.7L (Mopar 53041138AE) — $88.18Parker E-Z Mate EZ-501-8FP Pneumatic Push-to-Connect Coupler, 1/2 in Female NPT — $70.66
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McDonnell & Miller

McDonnell & Miller 173502 Model 157S Low Water Cut-Off & Pump Controller

Mfr #: 173502BB #: mcdonnell-miller-173502-mcdonnell-miller-173502-model-157s-low-watUPC: 751875036297
Last verified Oct 2, 2026 — price check expired
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🗎 Product description from the manufacturer spec sheet

McDonnell & Miller model number 157S (MPN 173502) is a combination float-operated low water cut-off and pump controller for steam boilers with an integral water column. The controller has 1/2 inch NPT tappings for gauge glass and tri-cocks and features an automatic reset with two 120 volt bi-metal snap switches: one single pole, single throw switch for pump control, and one single pole, double throw switch for low water cut-off and alarm actuation. Its maximum pressure is 150 psi and it has a tapped 1 inch FIP connection.

▦ Specifications spec-checked before it ships

Control

Control Switch
SWA-150S
Control Reset
Automatic
Control Connection
NPT

More specifications

Model
157S
M&M Series
Series 157S
Application
Steam Boilers
Voltage
120V, 240V
Connection Size
1"
Max Pressure
150 psi
Installation Method
1" Equalizing Piping
Replaces
173500 (Model 157)
⌗ Cross-references every known SKU, MFR & MPN
MPN173502
UPC751875036297