1F90 and 1F97
Addendum to
WHITE-RODGERS
INSTALLATION INSTRUCTIONS
FAILURE TO READ AND FOLLOW ALL INSTRUCTIONS CAREFULLY
BEFORE INSTALLING OR OPERATING THIS CONTROL COULD CAUSE
PERSONAL INJURY AND/OR PROPERTY DAMAGE.
PRECAUTIONS
Ifindoubtaboutwhetheryourwiringismillivolt,line,orlow
voltage, have it inspected by a qualified heating and air
conditioning contractor, electrician, or someone familiar
with basic electricity and wiring.
CAUTION
!
To prevent electrical shock and/or equipment
damage, disconnect electric power to system, at
main fuse or circuit breaker box, until installa-
tion is complete.
Do not exceed the specification ratings.
All wiring must conform to local and national electrical
codes and ordinances.
Do not short out terminals on gas valve or pri-
marycontroltotest.Shortorincorrectwiringwill
burn out thermostat and could cause personal
injury and/or property damage.
INSTALLATION
WHENTHISTHERMOSTATISCONNECTEDTOSOME If you observe any or all of these conditions after installing
SYSTEMSTHATUSEHIGHIMPEDANCEINPUTELEC- thermostat,youcancorrectsystemoperationbyinstalling
TRONIC MODULES, YOU MAY OBSERVE THE FOL- isolationrelaysbetweenthethermostatandtheelectronic
LOWING CONDITIONS.
ignition module. Figures 1 and 2 show how three isolation
relays can be installed [one each for the fan (G), heat (W),
andcool(Y)].Youmaynotneedtoinstallallthreeisolation
relays to correct the operation conditions.
1. The furnace fan may turn on when heat has not been
called, ormaynotturnoffwhenthermostatissatisfied
and call for heat ends.
2. The furnace may not turn off when thermostat is
satisfied and call for heat ends.
3. The air conditioner may not turn off when thermostat
is satisfied and call for cool ends.
Figure 1 shows a single transformer heating/cooling sys-
tem, with isolation relays installed in the heating (W),
cooling (Y), and fan (G) circuits. To simplify the diagram,
limit and safety switches are not shown here, although
they will be found either in the low or high voltage circuit.
Limit and safety switches must be retained. Refer to the
equipment manufacturer’s system wiring diagram for the
location of limit and safety switches.
THERMOSTAT
Red Jumper Wire
RH
W
Y
G
RC
Line
Voltage
24 VAC
WARNING
!
Heating Cooling
System System
Fan
Relay
Transformer
DO NOT REMOVE OR WIRE AROUND LIMIT AND
SAFETY SWITCHES WHEN INSTALLING ISOLA-
TION RELAYS.
Figure 1. Wiring for single transformer systems
WHITE-RODGERS DIVISION
EMERSON ELECTRIC CO.
9797 REAVIS ROAD
ST. LOUIS, MISSOURI 63123-5398
PART NO. 37-5426A
Printed in U.S.A.
9507
R
Download from Www.Somanuals.com. All Manuals Search And Download.
|