Install Instructions

A19BAC, A28AA Installation Instructions 3
Check for correct operation in the
following manner.
1. A19BAC -- Ventilating or
Cooling: Turn dial clockwise to
a setting above space
temperature. Fan or cooling
system should be off. When
you turn the dial
counterclockwise, the fan or
cooling system should turn on
approximately at the dial
setting.
A19BAC -- Heating: Turn dial
clockwise above the space
temperature; the heating unit
should be on. When you turn
the dial counterclockwise, the
heating unit should turn off
approximately at the dial
setting.
2. A28AA -- If wiring is similar to
Fig. 8, fan should start at
approximately space
temperature and should
change to high speed as the
dial is turned counterclockwise
to a lower temperature setting.
If similar to Fig. 9, the damper
should open as the dial is
turned counterclockwise. The
devices should act in reverse
sequence when the dial is
turned clockwise to a higher
setting.
3. If control devices do not
operate in the manner
described above, check all
wiring for short circuits and
tightness of wiring
connections. If controlled
devices operate in reverse
(start in high or fully open
position), check wiring.
Repairs and Replacement
Field repairs must not be made. For
replacement thermostat contact the
nearest Johnson Controls
distributor.
Adjustment Stop Bracket
with Slot and Screw
Fig. 3 – All models have a screw
type adjustment stop. Loosen
and move stop screw to the stop
setting desired. Tighten screw
after setting is made.