Watts F256661 Valve

The Watts F256661 140S-3 150/210 FS is a freeze stat / temperature limit control used in HVAC systems to protect coils, heat exchangers, and air handling equipment from low-temperature damage. It functions by monitoring temperature and initiating a control response when conditions approach unsafe levels, helping prevent coil freeze-up and system failure.

In the field, this type of control is commonly used in air handlers, hydronic coil assemblies, and packaged HVAC units where reliable freeze protection is required. The 150/210°F operating range supports different staging and safety control strategies depending on the system design. Proper installation and secure sensing contact are critical to ensure accurate temperature response and dependable protection.

Key benefits:

• Provides freeze protection for HVAC coils and heat exchangers
• Helps prevent equipment damage caused by low-temperature conditions
• Functions as a temperature limit safety control (aquastat-style operation)
• Supports stable HVAC system cycling and protection logic
• Replacement-compatible with Watts 140S-3 style controls (F256661)

Common questions:
What does this part do? It monitors temperature and helps prevent freezing in HVAC systems.
Where is it used? Typically installed on coils, ducts, or air handling equipment.
Is it a freeze stat? Yes, it is used for freeze protection and temperature limiting functions.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.

F256661 is the cross for 0256661