39
Section C - Components, cont’d.
RC to terminals G and H. Now place one lead from bulb to
AC white terminal and the other lead from bulb to AC white
terminal and the other lead from bulb to HIGH FAN. The
bulb should illuminate. Remove the jumper and the bulb
should not illuminate. If these tests are correct, the relay
board is good. DO NOT replace it. If any one of these tests
are incorrect, replace the relay board.
C17b.
Analog Printed Circuit Board
Control Box
The Analog Control Box comes in 3 different configurations,
that are not interchangeable. The Analog Control Board
consists of several relays, plug receptacles and other com-
ponents. If any one of these are defective the
entire Ana-
log Control Box should be replaced.
The Analog Control Box works with the Analog Thermostat
to change or switch AC circuits that control the operation of
the Duo-Therm Unit.
1. Air Conditioners
To verify circuits are being completed by the Analog Con-
trol Box, you would first disconnect the 6-pin plug connec-
tor from the Analog Control Box.
Using a 115 volt AC incandescent bulb, check from termi-
nal 5 (white-common) to the other terminals to determine if
a particular circuit is completed through the Analog Control
Box. If the Circuit is completed the light will illuminate.
Terminal 1 is a blue wire and the compressor circuit.
Terminal 2 is a black wire and the High Fan circuit.
Terminal 3 is a yellow wire and not used.
Terminal 4 is a red wire and the Low Fan circuit.
Terminal 5 is a white wire and the common AC connec-
tion.
Terminal 6 is a green/yellow wire and chassis ground.
Note:
DO NOT use a voltmeter to do these checks as it will
give erroneous readings.
FIG. C35
If the circuit is completed and a component is not operat-
ing, the problem is in the rooftop unit.
2. Air Conditioners with Heat Strip
To verify circuits are being completed by the Analog Con-
trol Box, you would first disconnect the 6-pin plug connec-
tor from the Analog Control Box.
Using a 115 volt AC incandescent bulb, check from termi-
nal 5 (white-common) to the other terminals to determine if
a particular circuit is completed through the Analog Control
Box. If the circuit is completed the bulb will illuminate.
Terminal 1 is a blue wire and the compressor circuit.
Terminal 2 is a black wire and the High Fan circuit.
Terminal 3 is a yellow wire and not used.
Terminal 4 is a red wire and the Low Fan circuit.
Terminal 5 is a white wire and the common AC con-
nection.
Terminal 6 is green/yellow wire and chassis ground.
To verify heat strip operation disconnect the 3-pin plug and
using a 115 volt AC bulb, check from Terminal 1 to Termi-
nal 3. If the circuit is completed the bulb will illuminate.
Note:
DO NOT use a voltmeter to do these checks as it
will give erroneous readings.
If the circuit is completed and a component is not operat-
ing, the problem is in the rooftop unit.
3. Roof Top Heat Pump
To verify circuits are being completed by the Analog control
Box, you would first disconnect the 6-pin plug connector
from the Analog Control Box.
Using a 115 volt AC incandescent bulb, check from termi-
nal 5 (white-common) to the other terminals to determine if
a particular circuit is completed through the Analog Control
Box. If the circuit is completed, the light will illuminate.
Terminal 1 is a blue wire and the compressor circuit.
Terminal 2 is a black wire and the High Fan circuit.
Terminal 3 is a yellow wire and reversing valve circuit.
This circuit is energized in the cooling mode and
not energized in the heat pump mode.
Terminal 4 is a red wire and the Low Fan circuit.
Terminal 5 is a white wire and the common AC con-
nection.
Terminal 6 is green/yellow wire and chassis ground.
Note:
DO NOT use a voltmeter to do these checks as it
will give erroneous readings.
If the circuit is completed and a component is not operat-
ing, the problem is in the rooftop unit.
Manual
Compliments
of
Northwest
RV
Supply
Printed
From
http://www.nwrvsupply.com
