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MCDONNELL 51-S-HD Water Feeder - Replacement HVACR Pumps, Valves & Tubing
MCDONNELLReplacement HVACR Pumps, Valves & Tubing

MCDONNELL 51-S-HD Water Feeder

MCDONNELL Replacement HVACR Pumps, Valves & Tubing. Specifications: Product Type: Water Feeder.

SKU 3G-OTH-84143

Also listed as: 51SHD · 51 S HD

Brand
MCDONNELL
Item
51-S-HD Water Feeder
Category
Replacement HVACR Pumps, Valves & Tubing
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

MCDONNELL
Manufacturer Part Number
51-S-HD
Product Type
Water Feeder

Technical Documents

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MCDONNELL Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

MCDONNELL Replacement HVACR Pumps, Valves & Tubing. Specifications: Product Type: Water Feeder.

Frequently Asked Questions

What is a McDonnell & Miller 51-S-HD water feeder used for?

The McDonnell & Miller 51-S-HD water feeder automatically maintains water level in low-pressure steam boilers and hydronic heating systems. It prevents dry-firing and boiler damage by adding water when the level drops, ensuring safe, reliable operation in commercial and industrial HVAC applications.

What are the specifications of the McDonnell & Miller 51-S-HD water feeder?

The McDonnell & Miller 51-S-HD is a water feeder with manufacturer part number 51-S-HD. It is designed for low-pressure steam and hot water boilers. For exact pressure ratings, connection sizes, and electrical requirements, consult the manufacturer's datasheet or contact 3G Electric for technical support.

Where to buy a McDonnell & Miller 51-S-HD water feeder worldwide?

3G Electric supplies the McDonnell & Miller 51-S-HD water feeder to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this genuine replacement part.

How to install a McDonnell & Miller 51-S-HD water feeder?

Install the McDonnell & Miller 51-S-HD water feeder according to the manufacturer's instructions and local codes. Typically, mount it on the boiler's equalizing pipe, connect the supply line, and wire the low-water cutoff. Always isolate power and drain the system before installation. Consult a qualified technician.

Used in

Common applications for MCDONNELL
Steam boiler low-water cutoff — McDonnell & Miller 61 level control
Condensate receiver level monitoring — McDonnell & Miller RS-4-BR-1 4-level sensor
HVACR pump suction filtration — McDonnell & Miller 340700 strainer basket assembly
Flow switch head replacement — McDonnell & Miller 63-HD head mechanism
Boiler control circuit safety — McDonnell & Miller 7-BM electrical switch with manual reset
Field servicing of flow switches — McDonnell & Miller 310452 cartridge kit

MCDONNELL Products

3G Electric supplies MCDONNELL replacement hvacr pumps, valves & tubing. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
This water feeder automatically maintains water level in low-pressure steam boilers and hydronic heating systems. It adds water when levels drop, ensuring safe boiler operation. Suitable for use as a replacement component in HVACR pumps, valves, and tubing
MCDONNELL
This water feeder automatically maintains water level in low-pressure steam boilers and hydronic heating systems. It adds water when levels drop, ensuring safe boiler operation. Suitable for use as a replacement component in HVACR pumps, valves, and tubing
Automatic water feeder for maintaining water levels in hydronic heating systems. Designed for replacement in HVACR pumps, valves, and tubing applications. Helps prevent low-water conditions in boilers
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Automatic water feeder for maintaining water levels in hydronic heating systems. Designed for replacement in HVACR pumps, valves, and tubing applications. Helps prevent low-water conditions in boilers
Automatic water feeder for maintaining minimum water level in low-pressure steam boilers and hydronic heating systems. Used in HVAC applications to prevent dry-fire conditions and protect boiler equipment
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Automatic water feeder for maintaining minimum water level in low-pressure steam boilers and hydronic heating systems. Used in HVAC applications to prevent dry-fire conditions and protect boiler equipment
Automatic feeder for maintaining water levels in boiler systems. Designed for commercial and industrial HVAC and steam applications to prevent low-water conditions
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Automatic feeder for maintaining water levels in boiler systems. Designed for commercial and industrial HVAC and steam applications to prevent low-water conditions
This level control feeder automatically maintains water level in boiler systems and process equipment. It feeds water when levels drop to prevent dry-fire damage and system downtime. Suitable for commercial and industrial HVACR applications
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This level control feeder automatically maintains water level in boiler systems and process equipment. It feeds water when levels drop to prevent dry-fire damage and system downtime. Suitable for commercial and industrial HVACR applications
Level control feeder for automatic water level maintenance in boiler systems. Used in HVAC and steam boiler applications to prevent low-water conditions. Part number 51-2
MCDONNELL
Level control feeder for automatic water level maintenance in boiler systems. Used in HVAC and steam boiler applications to prevent low-water conditions. Part number 51-2

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Level control for monitoring and regulating liquid levels in boilers, tanks, and receivers. Used in HVAC and industrial systems to help prevent low-water conditions that can damage equipment
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The MCDONNELL 64-B is a level control float block used in HVAC and industrial systems to monitor and regulate liquid levels in boilers, tanks, and receivers. It provides on/off control for pumps, valves, or alarms, helping maintain safe operating conditions in steam and hot water systems
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Level control tapping for HVAC and boiler systems. Monitors and regulates water or liquid levels to prevent low-water conditions in steam boilers and hot water systems. Used in replacement HVACR pumps, valves, and tubing applications
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Level control tapping for HVAC and boiler systems. Monitors and regulates water or liquid levels to prevent low-water conditions in steam boilers and hot water systems. Used in replacement HVACR pumps, valves, and tubing applications
Level control for monitoring and regulating liquid levels in boilers, tanks, and receivers. Used in HVAC and industrial systems to help prevent low-water conditions. Product type: Level Control
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Replacement cartridge and strainer kit for HVACR pumps, valves, and tubing. Compatible with manufacturer part number 101A. Used to filter debris and maintain fluid flow in commercial heating and cooling systems
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Replacement cartridge and strainer kit for HVACR pumps, valves, and tubing. Compatible with manufacturer part number 101A. Used to filter debris and maintain fluid flow in commercial heating and cooling systems
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This low water cut-off and pump controller is used in steam and hot water boilers to prevent dry-fire damage. It automatically shuts down the burner and controls the feed pump when water level drops. Suitable for replacement in HVACR pumps, valves, and tubing applications
Replacement casting for HVACR pumps, valves, and tubing systems. Compatible with manufacturer part number 193. Used to restore proper flow and pressure regulation in heating, cooling, and refrigeration applications
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