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MCDONNELL 551-S-HD Water Feeder - Replacement HVACR Pumps, Valves & Tubing
MCDONNELLReplacement HVACR Pumps, Valves & Tubing

MCDONNELL 551-S-HD Water Feeder

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

SKU 3G-OTH-84469

Also listed as: 551SHD · 551 S HD

Brand
MCDONNELL
Item
551-S-HD Water Feeder
Category
Replacement HVACR Pumps, Valves & Tubing
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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
551-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 the MCDONNELL & MILLER 551-S-HD water feeder used for?

The MCDONNELL & MILLER 551-S-HD water feeder is used in commercial and industrial hydronic heating systems to automatically maintain proper water levels in boilers. It helps prevent low-water conditions that can cause equipment damage or shutdowns.

What are the specifications of the MCDONNELL & MILLER 551-S-HD water feeder?

The MCDONNELL & MILLER 551-S-HD is a water feeder with manufacturer part number 551-S-HD. It is designed for replacement in HVACR pumps, valves, and tubing applications. For detailed technical specifications, consult the product datasheet or contact 3G Electric.

Where to buy the MCDONNELL & MILLER 551-S-HD water feeder worldwide?

You can source the MCDONNELL & MILLER 551-S-HD water feeder through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time.

How to install the MCDONNELL & MILLER 551-S-HD water feeder?

Install the MCDONNELL & MILLER 551-S-HD water feeder by shutting off power and water supply to the boiler. Mount the feeder per manufacturer guidelines, connect piping and wiring, then test for proper operation. Always follow local codes and the product manual.

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
MCDONNELL & MILLER Water Feeder: 51-S-HD Mfr Part #
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MCDONNELL & MILLER Water Feeder: 51-S-HD Mfr Part #
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
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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 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
Low water cut-off head mechanism for steam boilers and hot water systems. Automatically interrupts burner operation when water level drops below safe threshold to prevent dry-fire damage. Suitable for replacement in commercial and industrial HVACR pump, valve, and tubing assemblies
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Low water cut-off head mechanism for steam boilers and hot water systems. Automatically interrupts burner operation when water level drops below safe threshold to prevent dry-fire damage. Suitable for replacement in commercial and industrial HVACR pump, valve, and tubing assemblies

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