46
To check ACTIVE terminals, place one lead from ohm meter
to R terminal and the other lead to the ACTIVE terminal.
SWITCH
IF ROOM TEMP.
COMB.
IS ABOVE/BELOW
TERMINALS THAT
FAN
SETPOINT TEMP.
ARE “ON”
SWITCH
G Y
AUTO
ABOVE
X
X
BELOW
ON
ABOVE
X
X
BELOW
X
The heating and cooling thermostat has two switches on
the base. They are HEAT-OFF-COOL on the left side, and
FAN-AUTO-ON on the right. This thermostat will operate
an air conditioner and a furnace.
Section C - Components, cont’d.
FIG. C46
Verify that the wiring to the thermostat is correct.
A three-connector cable 18 to 22 AWG is to be used for
low voltage connections. Low voltage wires in the control
compartment are marked “R”, “G” and “Y”. Route low volt-
age cable from thermostat to unit electrical box. Use .50
dia. snap-bushing for routing cable into electrical box. Se
Section C19.
Connect RC from thermostat to red wire in control com-
partment. Connect G or F from thermostat to blue wire in
control box. Connect Y from thermostat to yellow wire in
control box. Use wire nuts to ensure good connections.
When connecting a gas furnace to this thermostat, the RH
and W terminals are used.
To check the thermostat remove all wires. Next, using an
ohm meter, put the HEAT-OFF-COOL switch in the COOL
position. With room temperature above the setpoint tem-
perature and FAN switch in AUTO position, continuity should
exist between RC to Y and RC to G. With room tempera-
ture below set point temperatures, no continuity should exist
between RC to Y and RC to G. With FAN switch to ON
position, continuity should exist between RC to G regard-
less of room temperature.
With HEAT-OFF-COOL switch in the OFF position and FAN
switch in the AUTO position, no continuity should exist be-
tween RC to Y and RC to G regardless of room tempera-
ture. With FAN switch to ON position, continuity should exist
between RC to G and no continuity between RC to Y re-
gardless of room temperature.
With HEAT-OFF-COOL switch to HEAT and FAN switch to
AUTO position, no continuity should exist between RC to Y
and RC to G regardless of room temperature. With FAN
switch to ON position, continuity should exist between RC
to G and no continuity between RC to Y regardless of room
temperature. With room temperature below setpoint tem-
perature, continuity should exist between RH to W. With
room temperature above setpoint temperature no continu-
ity should exist between RH to W.
FIG. C47
To check ACTIVE terminals, place one lead from ohm meter
to RC (cooling) or RH (heating) terminal and the other lead
to the ACTIVE (ON) terminal.
SWITCH
COMBINATION
IF ROOM TEMP.
IS ABOVE/BELOW
SETPOINT TEMP.
ABOVE
BELOW
ABOVE
BELOW
ABOVE
BELOW
ABOVE
BELOW
ABOVE
BELOW
ABOVE
BELOW
TERMINALS THAT
ARE “ON”
SYSTEM
SWITCH
FAN
SWITCH
AUTO
ON
AUTO
ON
AUTO
ON
G Y W
X
X
X
X
X
X
X
X
X
X
X
COOL
HEA
T
OFF
Manual
Compliments
of
Northwest
RV
Supply
Printed
From
http://www.nwrvsupply.com