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3G Electric
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
Part Number
51-S-HD
Category
Replacement HVACR Pumps, Valves & Tubing
Available to Order
Also known as:51-S-HDMCDONNELL
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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
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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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