46
ST 5220
QM 1336.rev.01
PROBLEM
SOLUTION
CAUSE
The stage 1
variable speed
cooling fans run
continuously
when the room
temperature is
below the room
set point
(minimum
ventilation
cycle).
The stage 1 time off
is set to zero.
Set the stage 1 time off to
a value other than zero.
The wiring is incor-
rect.
Correct the wiring. Be sure
two different lines are connected
to each fan motor: line L1
modulated by the controller
should be combined with
another line (N for 115V or L2 for
230V) to activate the motor.
Also, be sure the
stage 1 COMMON is supplied by
line L1.
The mist is not
operating as
desired.
The mist time on and time off
are in minutes. Adjust the mist
time on and time off correctly.
The mist time on and
time off were incor-
rectly adjusted.
The cooling fans
are not running.
or
The heaters are
not turning on.
The wiring is incor-
rect.
Correct the wiring. Be sure
two different lines are connected
to each fan motor or heater: the
controller's output line L1 should
be combined with another line
(N for 115V or L2 for 230V) to
activate the fan motor or heater.
Also, be sure the stage's
COMMON is supplied by line L1.
The stage's fuse is
open.
Replace the fuse.
