Brochure

Tunstall Corporation
118 Exchange Street • Chicopee, MA 01013
© July 2014
We reserve the right to alter designs, specifications and information without notice.
Phone [phone] · Fax [phone]
www.tunstall-inc.com • www.maconcontrols.com
Bulletin-MTWZ-0714
Non-Electric Operators
THERMOSTATIC OPERATOR
DIRECT MOUNT w/REMOTE SENSOR
MTWZ
Operation
The sensor on the MTWZ 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 sen-
sor and the return spring are balanced to the room temperature selected, the valve disc stops in that posi-
tion to allow a certain amount of water or steam to flow through the valve. Ambient 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 built-in pressure absorbing spring.
Features and Benefits
• Valve-mounted setting knob and remote tem-
perature sensor
• Brass sensor, High sensitivity
• Fiberglass valve plug shaft
• Stainless steel capillary tube, 6’6” standard
length
• Longer capillary available, consult factory
• Fits all Macon NT series valves
• Replaces the valve-mounted sensors on built-in
convectors, etc., and where the valve-mounted
sensor is exposed to draft from doors and win-
dows
• Fully automatic - nonelectric, no wiring
• Manufactured to exacting standards using ex-
ceptionally high quality materials
• Each sensor is tested and re-checked to achieve
exact settings before leaving the factory
• Note that changing the actuator can be accom-
plished without draining the system
• All Macon thermostats can be locked at or lim-
ited to a specific temperature or temperature
range
• Simple one-trade installation
• Sensor guard furnished at no extra cost
• All Macon valves and thermostats conform to
ASHRAE Standard 102P-1983 and European
Standard EN 215/1215. We are also ISO 9001
certified (2002) and ISO 14001 certified (2002).
See reverse for
min/max field adjustment
(MTWZ shown with
Macon NT series valve)