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MCDONNELL & MILLER Low Water Cut-Off - Replacement HVACR Pumps, Valves & Tubing
MCDONNELLReplacement HVACR Pumps, Valves & Tubing

MCDONNELL & MILLER Low Water Cut-Off

MCDONNELL Replacement HVACR Pumps, Valves & Tubing. Specifications: Product Type: Low Water Cut-Off.

SKU 3G-OTH-77664

Also listed as: 157SRL · 157S RL

Brand
MCDONNELL
Item
& MILLER Low Water Cut-Off
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
157S-RL
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 Pumps, Valves & Tubing. Specifications: Product Type: Low Water Cut-Off.

Frequently Asked Questions

What is the MCDONNELL & MILLER 157S-RL low water cut-off used for?

The MCDONNELL & MILLER 157S-RL low water cut-off protects boilers and steam heating systems from damage caused by low water conditions. It uses a snap switch to interrupt burner operation when water level drops below safe limits, preventing dry-firing and potential equipment failure.

What are the specifications of the MCDONNELL & MILLER 157S-RL?

The MCDONNELL & MILLER 157S-RL is a low water cut-off with a snap switch. Its manufacturer part number is 157S-RL. It is designed for use in HVACR systems to monitor water level and automatically shut down the burner if water drops too low, ensuring safe boiler operation.

Where to buy the MCDONNELL & MILLER 157S-RL worldwide?

You can source the MCDONNELL & MILLER 157S-RL low water cut-off through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring you receive the correct part for your HVACR application.

How to install the MCDONNELL & MILLER 157S-RL low water cut-off?

Install the MCDONNELL & MILLER 157S-RL in the boiler water line according to manufacturer guidelines. Ensure proper electrical connections to the snap switch and burner circuit. Always follow local codes and consult a qualified technician for safe installation and testing of the low water cut-off.

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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Cross-referenced by specification & description
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This low water cut-off is designed for use in steam and hot water boilers to protect against low-water conditions. It automatically shuts down the burner when the water level drops, preventing dry-fire damage. Suitable for commercial and industrial HVAC systems
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This low water cut-off is designed for use in steam and hot water boilers to protect against low-water conditions. It automatically shuts down the burner when the water level drops, preventing dry-fire damage. Suitable for commercial and industrial HVAC systems

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