Johnson Controls A25 Series Technical Bulletin

A25 Series Warm Air Control with Manual Reset
The A25 Series Warm Air Control with Manual Reset
is designed to shut down fans, burners, dampers, etc.,
when the temperature of the sensed air becomes
greater than the controller's setpoint.
When the sensed temperature increases to the
controller's setpoint, the A25's switch will open.
Manual reset is required to reclose the electrical
circuit. The A25 may be used as a high limit control in
the supply air duct (or plenum) where a lockout type
control is desired or required by local code.

 Trip-free Reset Lever

 Pilot Duty Electrical Rating for
up to 600 Volts Maximum

Enclosed Switch

Rod and Tube Sensing

Element

Adjustable Duct
Mounting Flange

Wide Temperature Range
© 2016 Johnson Controls, Inc.
Part 24-7664-656, Rev. A
Code No. LIT-125118
Features and Benefits
Does not allow the reset switch to hold the contacts in a closed (on)
position
Allows direct control of high voltage motor starters
Protects switch contacts from dust
Provides maximum response and allows for a high maximum
sensing element temperature
Controls the depth of sensor insertion into the airstream;

compensates for insulation depth

Allows the A25 to be used with many applications
Product/Technical Bulletin A25
Figure 1: The A25 Series Warm Air Control
with Manual Reset
FANs 125, 121
Issue Date 0316
1