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3G Electric
MCDONNELL 150S-M Low Water Cut-Off - Replacement HVACR Controls, Switches & Thermostats
MCDONNELLReplacement HVACR Controls, Switches & Thermostats

MCDONNELL 150S-M Low Water Cut-Off

MCDONNELL Replacement HVACR Controls, Switches & Thermostats. Specifications: Product Type: Low Water Cut-Off.

SKU 3G-OTH-79753

Also listed as: 150SM · 150S M

Brand
MCDONNELL
Item
150S-M Low Water Cut-Off
Part Number
150S-M
Category
Replacement HVACR Controls, Switches & Thermostats
Available to Order
Also known as:150S-MMCDONNELL
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Payment
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Technical Specifications

MCDONNELL
Manufacturer Part Number
150S-M
Product Type
Low Water Cut-Off

Technical Documents

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

Product Description

MCDONNELL Replacement HVACR Controls, Switches & Thermostats. Specifications: Product Type: Low Water Cut-Off.

Frequently Asked Questions

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

The MCDONNELL & MILLER 150S-M low water cut-off is used to protect steam boilers and hot water heating systems from damage caused by low water conditions. It automatically shuts down the burner when water level drops below safe limits, preventing overheating and potential boiler failure in commercial and industrial applications.

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

The MCDONNELL & MILLER 150S-M is a low water cut-off control with manufacturer part number 150S-M. It is designed for replacement HVACR controls, switches, and thermostats. This device monitors water level in boilers and interrupts burner operation to prevent dry-firing, ensuring safe system operation.

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

You can source the MCDONNELL & MILLER 150S-M low water cut-off 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 on this replacement HVACR control.

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

Install the MCDONNELL & MILLER 150S-M by mounting it on the boiler water column or tapping in the side of the boiler at the recommended water line. Connect electrical wiring per the manufacturer's diagram, ensuring proper grounding. Test operation by lowering water level to verify burner shutdown. Always follow local codes and the OEM 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 controls, switches & thermostats. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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