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Mcdonnell & Miller Series AF1 Air Flow Switches
Mcdonnell & MillerFlow Switches

Mcdonnell & Miller Series AF1 Air Flow Switches

Note: listed by manufacturer as obsolete/discontinued.

SKU 3G-OTH-02748

Brand
Mcdonnell & Miller
Item
Series AF1 Air Flow Switches
Category
Flow Switches
Available to Order
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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 Documents

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Mcdonnell & Miller Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

Note: listed by manufacturer as obsolete/discontinued.

Frequently Asked Questions

What is the McDonnell & Miller AF1 flow switch used for?

The McDonnell & Miller AF1 flow switch is used for general purpose applications requiring medium and high velocity flow detection. It is designed for duct sizes of 8 inches (203 mm) minimum, or 6 inches (152 mm) if the paddle is trimmed. Typical uses include HVAC and industrial process systems.

What are the specifications of the McDonnell & Miller AF1 flow switch?

The AF1 flow switch features a brass paddle that fits a minimum duct size of 8 inches (203 mm), or 6 inches (152 mm) when trimmed. It is designed for medium and high velocity flow requirements. Note that the manufacturer lists this model as obsolete or discontinued.

Where to buy the McDonnell & Miller AF1 flow switch in Singapore?

3G Electric supplies the McDonnell & Miller AF1 flow switch to Singapore. We handle logistics, customs clearance, and delivery to your facility. Contact us for current availability and lead time, as this model is listed as discontinued by the manufacturer.

How to install the McDonnell & Miller AF1 flow switch?

Install the AF1 flow switch by mounting it in a duct with the paddle oriented perpendicular to flow. Ensure the minimum duct size is 8 inches (203 mm), or 6 inches (152 mm) if the paddle is trimmed. Follow standard electrical wiring practices for the switch contacts. Always consult the manufacturer's manual for safety guidelines.

Used in

Common applications for Mcdonnell & Miller
Steam boiler low-water cutoff — McDonnell & Miller inline flow switches (e.g., FS-1) for automatic burner shutdown
Cooling water flow monitoring — McDonnell & Miller insertion-style switches (e.g., FS4-3D) in large-diameter pipes
Hazardous-area process lines — McDonnell & Miller FS7-4E with NEMA 7/9 enclosure for Class I, Div 1 locations
HVAC chilled water systems — McDonnell & Miller FS6-1 inline switch for pump flow verification
Industrial wastewater treatment — McDonnell & Miller FS4-3S stainless steel switch for corrosive fluid flow detection
Boiler feedwater control — McDonnell & Miller FS8-WJ with BSP connections for international installations

Mcdonnell & Miller Products

3G Electric supplies Mcdonnell & Miller flow switches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
This SANDPIPER air-operated double diaphragm pump is FDA-compliant for sanitary liquid transfer. It features a 1 1/2 in Tri-Clamp connection, 45 gpm flow rate, Santoprene check valves, and stainless steel seats. Suitable for food, dairy, beverage, and pharmaceutical applications
SANDPIPER
This SANDPIPER air-operated double diaphragm pump is FDA-compliant for sanitary liquid transfer. It features a 1 1/2 in Tri-Clamp connection, 45 gpm flow rate, Santoprene check valves, and stainless steel seats. Suitable for food, dairy, beverage, and pharmaceutical applications
This air-operated double diaphragm pump features a 1 1/2 in Tri-Clamp connection and delivers up to 45 gpm. It is constructed with PTFE check valves, stainless steel seats, and PTFE diaphragms with Buna backing. Suitable for fluid transfer in sanitary processes requiring FDA compliance
SANDPIPER
This air-operated double diaphragm pump features a 1 1/2 in Tri-Clamp connection and delivers up to 45 gpm. It is constructed with PTFE check valves, stainless steel seats, and PTFE diaphragms with Buna backing. Suitable for fluid transfer in sanitary processes requiring FDA compliance
SANDPIPER air operated double diaphragm pump with 316 stainless steel wetted parts. Features 2 1/2 in Tri-Clamp connections, delivers up to 200 gpm. Equipped with Santoprene check valves and stainless steel seats. Suitable for sanitary fluid transfer in food, dairy, beverage, and pharmaceutical applications requiring FDA compliance
SANDPIPER
SANDPIPER air operated double diaphragm pump with 316 stainless steel wetted parts. Features 2 1/2 in Tri-Clamp connections, delivers up to 200 gpm. Equipped with Santoprene check valves and stainless steel seats. Suitable for sanitary fluid transfer in food, dairy, beverage, and pharmaceutical applications requiring FDA compliance
Air-operated double diaphragm pump with 2 1/2 in Tri-Clamp connections, delivering up to 200 gpm. Wetted parts include PTFE check valves, stainless steel seats, and PTFE diaphragms with Santoprene backing. Suitable for sanitary fluid transfer in hygienic processing environments
SANDPIPER
Air-operated double diaphragm pump with 2 1/2 in Tri-Clamp connections, delivering up to 200 gpm. Wetted parts include PTFE check valves, stainless steel seats, and PTFE diaphragms with Santoprene backing. Suitable for sanitary fluid transfer in hygienic processing environments

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