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

Part Number

551-S-HD

Local availability & support

Payment: Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

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

Commercial boiler rooms — McDonnell & Miller low water cut-offs (e.g., Part 69) for steam and hot water boilers to prevent dry-fire.

Industrial steam systems — McDonnell & Miller water feeders (e.g., 51-S-HD) to maintain water level in low-pressure steam boilers.

HVAC hydronic heating — McDonnell & Miller level controls (e.g., 63-M) for monitoring liquid levels in expansion tanks and receivers.

Boiler maintenance and repair — McDonnell & Miller replacement head mechanisms (e.g., 94-HDLS) to restore function to existing controls.

Process equipment — McDonnell & Miller float blocks (e.g., 64-B) for on/off control of pumps and valves based on liquid level.

Steam boiler safety — McDonnell & Miller level control tappings (e.g., 63-B) to prevent low-water conditions in commercial and industrial systems.

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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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