Caleffi 521509 3-Way Thermostatic Mixing Valve
A three-way thermostatic mixing valve for blending hot and cold water to a stable temperature
- Precise temperature control via 3-way thermostatic mixing
- Reliable performance backed by Caleffi engineering
- Ready for HVAC system integration
- New condition ensures full operational life
- Direct manufacturer supply guarantees authenticity
3-Way Thermostatic Mixing Valve
The Caleffi 521509 is a 3-way thermostatic mixing valve designed for heating, ventilation and air-conditioning systems in recreational vehicles. It blends hot and cold water to deliver a stable outlet temperature for domestic fixtures. This component suits RV owners and technicians who need reliable temperature control in mobile plumbing installations.
Precise temperature regulation and system limits
The valve automatically adjusts the mix ratio to maintain the set temperature despite supply fluctuations, providing consistent comfort at showers and taps. It handles normal RV demand without pressure drop, but cannot compensate when the hot-water source is exhausted or the cold supply fails. In those conditions the outlet temperature follows the remaining inlet.
Replaces worn or non-thermostatic fittings
This unit upgrades older manual mixing valves or direct-feed connections that lack automatic balancing, eliminating scald risk and temperature swings. The jump is worthwhile when the existing fitting cannot hold a steady temperature under varying park-supply pressures. It does not suit systems that require electronic modulation or integration with a central building-management controller.
How it compares
Measured against everything we stock in Fans, Vents & Climate Control, at today’s prices. Recalculated every night.
- Price $127.99
- Pricier than about 67% of the 328 comparable items (median $68.99).
Specifications
| Product | |
|---|---|
| Brand name | CALEFFI |
Questions about this item
Will the Caleffi 521509 valve connect to my existing RV plumbing without special adapters?
The valve uses 3/4 inch connections, so check your current fittings match that size before installation.
How can I verify the Caleffi 521509 is regulating temperature correctly after fitting it?
Run hot and cold water through the valve, then measure the mixed output with a thermometer to confirm it reaches the set point.
Does the Caleffi 521509 package include gaskets or tailpieces, or must I buy them separately?
Only the 3-way thermostatic mixing valve body is supplied; any required seals or connection fittings must be purchased separately.
More in Fans, Vents & Climate Control
