Chore-Tronics 2 Control - Equipment and Potentiometer Troubleshooting

Chore-Tronics® 2 Control Troubleshooting
MT1843B
95
Equipment and Potentiometer Troubleshooting
Problem Possible Cause Possible Solution
Display difficult to read. A.) Display contrast needs
adjusted.
B.) Back light on display board
unplugged or defective.
A.) See page 87 for procedure on
adjusting screen contrast.
B). Check two wire plug on Dis-
play board. Replace if defec-
tive.
Display Completely Blank. A.) Flat cable(s) between KB
board and Display board is
unplugged or defective.
B.) Defective Display board.
C.) Defective HI board.
D.) Defective KB Board
A). Check flat cable connections.
Replace cable if defective.
B). Replace Display Board.
C). Replace KD Board.
D.)Replace KB Board
The Control says that the pressure
in the house is .00" and will not
move.
There is a wire connection prob-
lem between the static pressure
monitor and the IO board. When
the static pressure monitor is dis-
connected from the IO Board the
Control defaults to a reading of
.00"
Check for wires being switched,
broken wires, wires not making a
good connection, etc. An easy
way to remember the wiring is
that the red wire is connected to
the positive terminal of both the
IO board and the static pressure
monitor.
Temperature Sensor reading very
low, but is not stuck on 0° F.
A.) Connections in Temperature
Sensor junction box, and/or I/
O Board have become loose
and/or corroded.
B.) Defective Temperature Sen-
sor.
A.)Check all Temperature Sensor
connections, correct any
problems.
B.) Replace Temperature Sensor.
Temperature Sensor reading very
high or shows a “#” in place of a
temperature reading.
A.) Moisture inside Temperature
Sensor junction box causing
short.
B.) A Break in the Temperature
Sensor wire is causing a
short.
C.) Defective Temperature Sen-
sor.
A.) Remove moisture from Sensor
box and recheck temperature.
B.) Check Sensor wire and wire
connections. Correct any
problems.
C.) Replace Temperature Sensor.
Temperature readings are not
steady (changing half a degree or
more every five seconds). It is
causing Tunnel Fans and heaters
to run at the same time.
There is excessive noise on the
Temperature Sensors. This can be
caused by not using a Twisted Pair
Wire for the Temperature Sensor,
running the Sensor wire inside
conduit with high voltage wire, or
using a shielded wire and ground-
ing the shield.
To prevent noise from bothering
the Sensors, use non-shielded
Twisted Pair Wire (part no.
42208) and run the wire by itself
away from high voltage wires.
Preferably the wire should also
enter the Control in a separate
place from the high voltage wire,
but this is not always possible. Do
not use Romex, SJO cord,
shielded wire, etc. as Tempera-
ture Sensor wire.