Johnson Controls Pneumatic High Volume T-4002-201

The Johnson Controls T-4002-201 is a high volume pneumatic thermostat for pneumatic control systems.

Pneumatic controls predate electronic building automation and remain in service in a great many commercial and institutional buildings, particularly schools, hospitals, and older office buildings. They operate on compressed air rather than electricity: a thermostat modulates air pressure in a control line, and that pressure operates dampers, valves, and actuators.

The high volume designation refers to the thermostat's air handling capacity. A standard thermostat supplies a limited air volume suited to a single small actuator; a high volume unit can drive larger actuators or several devices, or respond more quickly where the connected volume is substantial.

Pneumatic systems have real advantages that account for their longevity: the actuators are powerful and reliable, the system is inherently modulating rather than on-off, and there is nothing electronic to fail from surges or age.

Their maintenance requirement is air quality. The compressed air must be clean and dry, because moisture and oil carried into control lines foul restrictors and diaphragms. Compressor, dryer, and filter maintenance is what keeps a pneumatic system working.

Applications include commercial and institutional buildings with pneumatic HVAC control, including schools, hospitals, and older office buildings.

Brand

Johnson Controls

SKU

T-4002-201

Category

Pneumatic Controls

Weight

0.45 lbs

Dimensions

4.50" x 2.00" x 2.00"

Price

$218.00

Availability

In stock

Rating

3.6 / 5.0