Johnson Controls T25 User Manual

T25 Two-Stage Room Thermostat
Application Requirements
T25 thermostats are for line- or low-voltage service
requiring accurate control of two operating functions.
There are two stages of control for heating and
cooling with automatic changeover on three- and
four-pipe fan coil installations and similar
applications. Typical uses are for compressor
controls, relays, valves, fan coils, and other
applications where low differentials and accurate
sensing are required.
Installation
IMPORTANT: The T25 Series Thermostats are
intended to control equipment under normal
operating conditions. Where failure or malfunction
of the T25 Thermostats could lead to an abnormal
operating condition that could cause personal
injury or damage to the equipment or other
property, other devices (limit or safety controls) or
systems (alarm or supervisory systems) intended
to warn of, or protect against, failure or malfunction
of the T25 Thermostats must be incorporated into
and maintained as part of the control system.
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© 2002 Johnson Controls, Inc.
Part No. 24-9716-5, Rev. A
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Diameter
Figure 1: T25A Dimensions, in. (mm)
Parts Included
•
1 thermostat
•
1 Allen wrench
•
2 machine screws
Dimensions
Refer to Figure 1 for detailed dimensions of the T25
Two-Stage room Thermostat.
Mounting
Location Considerations
Mount the thermostat about 4 to 5 ft. (1.2 to 1.5 m)
above the floor on an interior wall, where it can sense
the average room temperature. It is designed for vertical
mounting and will produce the lowest operating
differentials when installed in this position.
Do not mount the thermostat where it may react to heat
or cold from water pipes, windows, doors, lamps,
sunlight, or other heat or cold sources.
On unit heater applications, place the thermostat below
and behind the heater in the path of air entering the unit,
not in the path of discharge air.
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Two Threaded
Studs
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Two Mounting Holes
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Installation Instructions T25
Issue Date 02/15/02
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