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MCDONNELL & MILLER Level Control Head Mechanism - Replacement HVACR Pumps, Valves & Tubing
MCDONNELLReplacement HVACR Pumps, Valves & Tubing

MCDONNELL & MILLER Level Control Head Mechanism

The MCDONNELL & MILLER Level Control Head Mechanism is a Low Water Cut-Off replacement part for HVACR pumps, valves, and tubing. It features a 150S-MD-HD snap switch and carries the manufacturer part number 150S-MD-HD.

SKU 3G-OTH-77605

Also listed as: 150SMDHD · 150S MD HD

Brand
MCDONNELL
Item
& MILLER Level Control Head Mechanism
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
150S-MD-HD
Snap Switch
150S-MD-HD Mfr Part #
Product Type
Low Water Cut-Off

Technical Documents

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

Product Description

The MCDONNELL & MILLER Level Control Head Mechanism is a Low Water Cut-Off replacement part for HVACR pumps, valves, and tubing. It features a 150S-MD-HD snap switch and carries the manufacturer part number 150S-MD-HD.

Frequently Asked Questions

What is the MCDONNELL & MILLER 150S-MD-HD low water cut-off used for?

The MCDONNELL & MILLER 150S-MD-HD is a low water cut-off used in steam and hot water boilers to protect against low-water conditions. It automatically shuts down the burner when water level drops, preventing boiler damage. This snap-switch mechanism is a replacement part for HVACR pumps, valves, and tubing systems.

What are the specifications of the MCDONNELL & MILLER 150S-MD-HD?

The MCDONNELL & MILLER 150S-MD-HD is a low water cut-off with a snap switch mechanism. Its manufacturer part number is 150S-MD-HD. It is designed as a replacement component for HVACR pumps, valves, and tubing. The product type is a level control head mechanism for boiler safety applications.

Where to buy the MCDONNELL & MILLER 150S-MD-HD worldwide?

You can source the MCDONNELL & MILLER 150S-MD-HD low water cut-off through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide locations. Contact us for availability and lead time on this replacement snap-switch mechanism.

How to install the MCDONNELL & MILLER 150S-MD-HD low water cut-off?

Install the MCDONNELL & MILLER 150S-MD-HD by first isolating power and draining the boiler to below the cut-off level. Mount the mechanism per manufacturer guidelines, ensuring proper float alignment. Wire the snap switch according to the boiler control circuit. Always follow local codes and 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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