The Johnson Controls F261MAH-V01C Fluid Flow Switch is a paddle-operated liquid flow switch designed to monitor fluid flow in HVAC, refrigeration, hydronic heating, cooling, and industrial fluid circulation systems. Part of the Johnson Controls PENN F261 Series, this standard-model switch responds to changes in liquid flow and provides electrical switching for equipment operation, control circuits, and low-flow protection applications.
 
The F261MAH-V01C features a single-pole, double-throw (SPDT) switch with an adjustable flow activation setting, allowing the control to respond when fluid flow increases or decreases.  Its Type 4 (NEMA 4) polycarbonate enclosure provides protection for indoor and outdoor installations, including high-humidity environments. The switch incorporates a 1-inch NPT threaded process connection and supports maximum fluid pressures of 290 PSIG (20 bar).
 
Designed for use with water, ethylene glycol solutions, treated water, and other compatible nonhazardous liquids, this flow switch accommodates fluid temperatures from -20°F to 250°F (-29°C to 121°C), subject to the manufacturer's operating limitations. A Viton diaphragm supports compatibility with various treated-water applications.
 
The F261MAH-V01C includes 1-inch, 2-inch, 3-inch, and 6-inch stainless steel flow paddles, a lock-tooth washer, and a stainless-steel paddle screw, supplied uninstalled for selection and installation according to pipe size and required flow conditions. Its standard electrical contacts support control and equipment interlock applications, with resistive ratings of 16 A at 24/120 VAC and 10 A at 208/240 VAC.
 
The Johnson Controls F261MAH-V01C is an appropriate replacement selection for obsolete Johnson Controls F61LB-1C, F61MB-1C, and F61MB-5C flow switches, subject to application and installation requirements.
 
 
Frequently Asked Questions
 

What are the Johnson Controls F261MAH-V01C used for?
The F261MAH-V01C monitors liquid flow in HVAC, refrigeration, hydronic, and industrial fluid systems. It can activate control circuits or help protect equipment when fluid flow falls below the required level.

What is the maximum pressure rating?
The Johnson Controls F261MAH-V01C supports maximum fluid pressures of 290 PSIG (20 bar).

What type of electrical switch does this model use?
The F261MAH-V01C uses a single-pole, double-throw (SPDT) switch with adjustable flow activation. It supports equipment control and interlock applications.

What pipe sizes are compatible with this flow switch?
The switch has a 1-inch NPT process connection and includes 1-inch, 2-inch, 3-inch, and 6-inch stainless steel paddles for use with compatible pipe sizes and flow conditions.

Can the F261MAH-V01C be installed outdoors?
Yes. Its NEMA 4 enclosure is designed for indoor and outdoor installations, including high-humidity environments, when installed according to the manufacturer's requirements.

What liquids are compatible with the F261MAH-V01C?
The switch can monitor water, ethylene glycol, treated water, and other compatible nonhazardous fluids. It is not intended for drinking-water applications.

Which older Johnson Controls flow switches does this model replace?
The F261MAH-V01C is the manufacturer's listed replacement model for F61LB-1C, F61MB-1C, and F61MB-5C. Installation conditions and electrical specifications should be checked when replacing an existing switch.