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Caleffi 301 series valves are installed on panel style radiators. They are connected to the bottom supply and return ports, providing fluid flow to the upper thermostatic valve built into the radiator. The center-to-center dimension is 50 mm, which is the common standard for all brands of panel radiators.

Two versions are available: Diverter style for one-pipe systems; Isolation style for two-pipe systems. Both have two ball shut-off valves and come as either a straight through flow pattern for floor connections or angled flow pattern for wall connections.

The diverter style offers an adjustable by-pass to send 30% to 50% of flow toward the radiator, factory-set for 35%. In addition, the diverter style contains a unique thermal break device in the return side (right leg) to prevent undesirable flow to the radiator due to thermo-syphoning when the thermostatic valve is closed, no call for heat.

  • Valve for panel radiators with built-in thermostatic valve unit.
  • One-pipe straight version (floor connections) fits 1/2” female radiator connections.
  • With adjustable bypass.
  • Balance knob
  • Max working pressure: 150 psi (10 bar)
  • Max working temp: 212°F (100°C)
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Manuals (1)
Product Type:
Thermostatic Radiator Valve
Max. Working Pressure:
150 psi
Max Temp (F):
1 Pipe
Valve Type:
Connection Size:
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