Caleffi 521509A Thermostatic and Pressure Balanced Mixing Valve

Caleffi 521509A Thermostatic and Pressure Balanced Mixing Valve delivers precise temperature control for domestic hot water, hydronic, and radiant heating systems. This Type 3-Way, adjustable thermostatic mixing valve features a 3/4 inch nominal size and soldered end connections on all ports, with an end-to-end distance of 5 inches. The brass body is lead-free, engineered for reliability in busy plumbing environments, and designed to maintain steady outlet temperatures even under fluctuating supply conditions.

Setpoint and performance specs ensure safe, predictable operation. The valve supports a set temperature range from 85 to 150°F, a temperature rating up to 200°F, and a pressure rating of 200 PSI. Its robust flow characteristics include a 1 GPM flow rate and a 3 CV flow capacity, with a maximum differential pressure of 20 PSI.

• Type: 3-Way thermostatic mixing valve
• Nominal size: 3/4 inch
• End connections: Soldered x Soldered x Soldered
• Flow rate / capacity: 1 GPM; 3 CV
• Set temperature: 85–150°F (200°F max)
• Pressure rating: 200 PSI; Max ΔP: 20 PSI
• Inclusions: Stainless steel spring, EPDM seal, PPO shutter
• Applications: Domestic hot water, hydronic and radiant heating
• Lead-free
• Standards: ASSE 1017, CSA B125.3, NSF/ANSI 372, IPC, IRC, UPC, NPC

Designed for professional installations, this valve provides dependable, code-compliant performance in a compact footprint with standard piping layouts and reliable safety features.