EVOL Wall Mounted Dial Operator




The sensor is wax-filled and the wax volume varies according to ambient temperature. The volume changes are transmitted to the valve stem via a liquid capillary system. The valve body has a return spring which closes the valve when the stem is under low pressure. When the force from the sensor and the return spring are balanced to the room temperature selected, the valve disc stops in that position to allow a certain amount of water or steam to flow through the valve. Temperature changes cause the valve disc to change position and thereby continuously modulate the flow so that the room temperature is maintained at the desired temperature. The unit is secured against damage from over pressure by a pressure absorbing spring.


  • Combined remote dial/sensor
  • Small dimensions
  • Brass sensor, High sensitivity
  • Manufactured to exacting standards using exceptionally high quality materials
  • Fiberglass valve plug shaft
  • Each sensor is tested and re-checked to achieve exact settings before leaving the factory
  • Stainless steel capillary tube, 6’6″ standard length
  • Note that changing of the actuator can be accomplished without draining the system
  • Longer capillary available, consult factory
  • All Macon thermostats can be locked at or limited to a specific temperature or temperature range
  • Fits all Macon NT series valves
  • Simple one-trade installation
  • Replaces the valve-mounted sensors on built-in convectors, etc., and where the valve-mounted sensor is exposed to draft from windows or doors
  • All Macon valves and thermostats conform to ASHRAE Standard 102P-1983 and European Standard EN 215/1215. We are also ISO 9001 certified (1994) and ISO 14001 certified (1998)
  • Fully automatic – nonelectric, no wiring
  • Shown with valve. Valve sold separately.


Temp. Range: 46º – 80ºF
Hystersis: 0.9ºF
Heat Transfer: 1.1ºF (Valve Housing Sensor)
Dead Time: 0.8 Minutes
Max. Differential Pressure: 20 psi
Sugg. Differential Pressure = 0.5 to 2.9 psi
Max. Water Temp.: 250ºF
Max. Storage & Ambient Temp.: 122ºF
Max. Steam Pressure: 15 psig
Max. Movement: 0.125
Nominal Opening: 0.018 (3.6ºF)
Long Term Test: 5000 cycles (1.3ºF)
0 = Off
* = 50ºF (Frost Protection)
1 = 54ºF
3 = 61ºF
5 = 68ºF
6 = 72ºF
7 = 75ºF
8 = 79ºF
9 = 82ºF

Click Here for Cross Reference chart of Previous Generations of Non-Electric Operators

BULLETIN: EVOL – Remote Sensor Thermostat