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MCDONNELLReplacement HVACR Pumps, Valves & Tubing

MCDONNELL 51-2-HD Head Mechanism

The MCDONNELL & MILLER 51-2-HD is a replacement head mechanism for HVACR pumps, valves, and tubing. This component is compatible with manufacturer part number 51-2 and carries the manufacturer part number 51-2-HD.

SKU 3G-OTH-76605

Also listed as: 512HD · 51 2 HD

Brand
MCDONNELL
Item
51-2-HD Head Mechanism
Category
Replacement HVACR Pumps, Valves & Tubing
Available to Order
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Technical specs
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Local availability & support — the Philippines

Delivery
5–8 business days door-to-door; Bureau of Customs clearance typically 2–4 business days.
Payment
Invoicing in PHP or USD. Bank transfer and corporate PO accepted.
Ships to
Manila, Quezon City, Cebu, Davao, Batangas

Technical Specifications

MCDONNELL
Manufacturer Part Number
51-2-HD
Product Type
Head Mechanism
Compatible Manufacturer Part Number
51-2

Technical Documents

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

Product Description

The MCDONNELL & MILLER 51-2-HD is a replacement head mechanism for HVACR pumps, valves, and tubing. This component is compatible with manufacturer part number 51-2 and carries the manufacturer part number 51-2-HD.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the MCDONNELL & MILLER 51-2-HD head mechanism used for?

The MCDONNELL & MILLER 51-2-HD is a replacement head mechanism used in HVACR pumps, valves, and tubing systems. It is designed to replace the 51-2 model, restoring proper flow control and safety shutoff functions in commercial heating and cooling applications.

What are the specifications of the MCDONNELL & MILLER 51-2-HD?

The MCDONNELL & MILLER 51-2-HD is a head mechanism with manufacturer part number 51-2-HD. It is compatible with manufacturer part number 51-2. This component is classified as a replacement part for HVACR pumps, valves, and tubing systems.

Where to buy the MCDONNELL & MILLER 51-2-HD worldwide?

3G Electric supplies the MCDONNELL & MILLER 51-2-HD head mechanism worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

How to install the MCDONNELL & MILLER 51-2-HD head mechanism?

To install the MCDONNELL & MILLER 51-2-HD, first isolate power and drain the system. Remove the old head mechanism and gasket, then fit the new 51-2-HD unit, ensuring proper alignment with the valve stem. Reassemble, pressurize, and test for leaks per manufacturer guidelines.

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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