Aprilaire Thermostat 8355 User Manual

®
ELECTRONIC THERMOSTATS  
MODEL 8355  
7 Day Programmable  
2 Heat / 2 Cool  
Heat Pump  
User’s Manual  
Installation and  
Programming  
Important Safety Information Warning:  
Always turn off power at the main power source by unscrewing  
fuse or switching circuit breaker to the off position before installing,  
removing, cleaning, or servicing thermostat.  
Read all of the information in this manual before installing or  
programming this thermostat.  
This is a 24V AC low-voltage thermostat. Do not install on voltages  
higher than 30V AC.  
All wiring must conform to local and national building and electrical  
codes and ordinances.  
Do not short (jumper) across terminals on the gas valve or at the  
system control to test installation. This will damage the thermostat  
and void the warranty.  
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Expand Contents

FIGURE 1  
Installing the Model 8355 Thermostat  
NOTE: For new installations, mount thermostat on inside wall, 4-5 feet  
above the floor. Do not install behind a door, in a corner, near air vents, in  
direct sunlight, or near any heat or steam generating fixtures. Installation  
at these places will affect thermostat operation.  
IMPORTANT: This thermostat is compatible with 100% lockout systems. To  
reset the system, turn thermostat to OFF position for at least 60 seconds.  
1. Turn power off to the heating and cooling systems.  
2. Place COOL-OFF-HEAT-EM in OFF position.  
COOL-OFF-HEAT-EM  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
FAN: AUTO-ON  
3. Place FAN: AUTO-ON switch  
into AUTO position.  
4. Remove the cover using a coin  
or screwdriver.  
M
E
5. Place thermostat against the wall at desired location. Make sure  
wires will feed through opening on base of thermostat.  
6. Mark placement of mounting holes. See Fig. 3. Set base aside.  
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FIGURE 3  
MOUNTING HOLES  
C
L
R
AM  
PM  
PROG  
MAN  
E
MORN DAY EVE NITE EER  
G
CHANGE  
SET PROG/MAN  
O
B
COOL OFF HEAT EM  
FAN AUTO ON  
7. Drill the marked holes using a 3/16" drill bit. NOTE: Enclosed plastic  
anchors do not require a drilled hole for drywall.  
8. Tap plastic anchors into the holes.  
9. Align base with plastic anchors and feed wires through opening.  
See Fig 4.  
FIGURE 4  
OPENING  
C
L
R
AM  
PM  
PROG  
MAN  
E
MORN DAY EVE NITE EER  
G
CHANGE  
SET PROG/MAN  
O
B
COOL OFF HEAT EM  
FAN AUTO ON  
10. Secure base to wall with supplied screws.  
11. Connect wires to terminal strip. Refer to wiring diagrams on other  
side of this sheet. Make sure wire connections are secure.  
12. Install two "AA" ENERGIZER brand batteries or equivalent into  
battery compartment. Be sure to match positive (+) ends of batteries  
with positive (+) battery terminals in the battery compartment.  
13. Replace cover onto thermostat by snapping into place.  
14. Turn on power to system. Test thermostat as described in the  
following section.  
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Programming Guide  
Set Time of Day, Day of Week,  
Temperature Differential, Residual Cooling  
1. Press SET & PROG/MAN.  
Release simultaneously.  
SET PROG/MAN  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
Press  
or  
to change  
Time of Day.  
2. Press  
3. Press  
1=MO  
2=TU  
3=WE  
4=TH  
5=FR  
SET  
To Change Day of Week  
5. Press  
4. Press  
SET  
6=SA  
7=SU  
To change 1st Stage  
Temperature Differential  
NOTE: The Temperature Differential is Factory preset at 1°. This means  
that whenever the room temperature changes by one full degree from  
the temperature setting, the system will turn on. If the system turns on  
too often, increase the temperature differential.  
6. Press  
7. Press  
SET  
To change 2nd Stage  
Temperature Differential  
NOTE: The Second Stage Temperature Differential is Factory preset at 2°.  
8. Press  
9. Press  
SET  
To change  
Residual Cooling  
NOTE: The residual cool feature will keep the system fan on for an  
additional 30, 60 or 90 seconds after the compressor cycles off in cool  
mode. The residual cool feature can only be set in the cool mode.  
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Changing Fahrenheit (F) to Celsius (C)  
Press and Hold SET  
Press  
SET  
Release both simultaneously.  
Energy Efficient Recovery  
The energy efficient recovery feature looks ahead up to 2 hours prior to the  
end of the setback (or set-up) period to begin monitoring performance and  
calculating when to turn on your system. It also determines whether the aux-  
iliary heat or cool stages should be activated prior to setpoint time to meet  
your chosen setpoint temperature. The thermostat will indicate “EER” in the  
display when this program feature is active. The energy efficient recovery  
feature will lockout the auxiliary stages until 20 minutes prior to upcoming  
setpoint time to utilize the most energy efficient first stage. The auxiliary  
stages of heating and cooling will be available during this lock-out period  
to maintain the setpoint temperature should the system not be able to  
keep up with the heating or cooling demand.  
Simple Programming Mode  
COOL-OFF-HEAT-EM  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
SET  
P
1. Place COOL-OFF-HEAT-EM  
in COOL or HEAT position.  
2. Press & Hold SET. Press the  
Release simultaneously.  
button.  
3. The MORN indicator should be blinking. Program the Time-of-Day and  
the temperature as outlined in the Setting Daily Program section.  
NOTE: Use this function to set all 7 days of the week with the same program.  
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Setting Daily Programming  
1. Place COOL-OFF-HEAT-EM  
in COOL position.  
COOL-OFF-HEAT-EM  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
SET PR  
2. Press SET button. The display will show a  
number from 1 to 7. This number represents  
the day of the week to be programmed. If  
programming individual days, press either  
or  
button to adjust the day of the week  
to program (1=Mon., 2=Tues., etc.).  
3. Press SET. Press  
4. Press SET.  
or  
to change MORN time.  
SET PR  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
5. Press  
or  
to change  
MORN temperature.  
6. Repeat Steps 2-5 for DAY, EVE, and NITE.  
7. Press SET to finish this day.  
COOL-OFF-HEAT-EM  
8. Repeat steps 2–7 above to program  
any other day of the week.  
9. Shift COOL-OFF-HEAT-EM to HEAT position.  
10. Repeat steps 2-7 to program HEAT (winter) settings.  
Begin Programmed Operation  
1. Place FAN: AUTO-ON  
into AUTO.  
FAN: AUTO-ON  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
COOL-OFF-HEAT-EM  
SUMMER  
2. Place COOL-OFF-HEAT-EM  
into COOL or HEAT,  
depending upon the season.  
COOL-OFF-HEAT-EM  
7
WINTER  
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3. Press PROG/MAN button  
until indicator is in PROG position.  
ET PROG/MAN  
C
PROG  
MAN  
AUX CHECK EMER  
PROG  
MAN  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
NOTE: While in the Cool or Heat mode, once the thermostat turns the system  
off, a built-in delay keeps the compressor from turning on for about 5 minutes.  
This protects the compressor. No additional time delay relay (delay on break)  
is necessary.  
Temporary Program Override  
To temporarily increase or decrease temperature  
Press  
or  
PROG  
MAN  
AUX CHECK EMER  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
The thermostat will automatically return to the program at the next  
scheduled setting change or after four hours.  
Manual Operation  
Manual operation allows continuous override of the program settings.  
1. Press PROG/MAN until indicator is in MAN position.  
PROG  
MAN  
AUX CHECK EMER  
T
PROG/MAN  
PROG  
MAN  
SET PROG/MAN COOL-OFF-HEAT-EM FAN: AUTO ON  
-
2. Press or  
to adjust  
temperature settings.  
RESET BUTTON  
Reset  
C
L
R
To reset the thermostat  
to factory pre-programmed  
conditions, press the reset  
button located directly to  
the right of the display.  
AM  
PM  
PROG  
MAN  
E
G
MORN DAY EVE NITE EER  
CHANGE  
SET PROG/MAN  
O
B
COOL OFF HEAT EM  
FAN AUTO ON  
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To Test Thermostat  
WARNING: DO NOT SHORT (JUMPER) ACROSS TERMINALS OF GAS  
VALVE OR SYSTEM CONTROL TO TEST OPERATION. THIS WILL DAMAGE  
THE THERMOSTAT AND VOID YOUR WARRANTY.  
CAUTION: Do not switch system to cool if the temperature is below  
50°F (10°C). This can damage the air conditioning system and cause  
personal injury.  
COOL-OFF-HEAT-EM  
1. Place the COOL-OFF-HEAT-EM  
switch into the COOL position  
2. Press the button until the temperature  
setting is at least 3 degrees below the room temperature. The air  
conditioning system should turn on within a few seconds.  
NOTE: While in the Cool or Heat mode once the thermostat turns the system  
off, a built-in delay keeps the compressor from turning on for about 5 minutes.  
This protects the compressor. No additional time delay relay (delay on break)  
is necessary.  
COOL-OFF-HEAT-EM  
3. Put the COOL-OFF-HEAT-EM switch into  
the OFF position. The air conditioning  
system should turn off. The fan may  
continue to run for a short period of time.  
COOL-OFF-HEAT-EM  
4. Put the COOL-OFF-HEAT-EM switch  
into the HEAT position.  
5. Press the button until the temperature setting is at least  
3 degrees above room temperature. The heating system should turn  
on. The fan may not turn on immediately, depending upon the fan  
delay built into the furnace.  
COOL-OFF-HEAT-EM  
6. Put the COOL-OFF-HEAT-EM switch  
into the OFF position. The heating  
system should turn off. Once again,  
the fan may have a delay.  
FAN: AUTO - ON  
7. Put the FAN: AUTO-ON switch  
to the ON position. The blower  
fan should turn on.  
FAN: AUTO-ON  
8. Put the FAN: AUTO-ON switch  
to the AUTO position. The blower  
fan should turn off.  
LED Indicators  
The LED indicators are used to indicate system activity. The AUX indicator  
illuminates during a call for second stage heating. The auxiliary stages are  
used to maintain comfort during extremes in weather conditions. If the  
AUX LED is illuminated too frequently during periods of moderate temper-  
ature, check the differential settings (page 5).  
The CHECK indicator is used to monitor system status. If the CHECK  
indicator is illuminated, call your local HVAC service provider.  
The EMER indicator is illuminated only when the system switch is moved  
to the EM, emergency heat position. The EM position is only used when  
the primary stage of heat is not functioning or requires service.  
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Troubleshooting  
SYMPTOM  
REMEDY  
Thermostat does not turn  
on system.  
Check Wiring  
(see INSTALLATION).  
Check fuse. Replace with 3 amp  
fuse if fuse has opened. Five  
minute compressor short cycle  
protection may be in effect. Press  
RESET to override. NOTE: This will  
erase programming.  
Thermostat turns on and off too  
frequently.  
Increase Temperature Differential  
(see PROGRAMMING).  
Display is blank, flashing or  
constant "LO BAT."  
Replace batteries.  
Time shown on display is not the  
current time of day.  
Change time of day setting  
(see PROGRAMMING).  
Thermostat does not follow  
program.  
Thermostat in MANUAL mode  
(see PROGRAMMING).  
Thermostat may not have been  
programmed in HEAT or COOL  
position. Verify program.  
Check AM/PM indicators at time  
of day and programmed time  
changes (see PROGRAMMING).  
Verify program and day of week  
is correct (see PROGRAMMING).  
To view or change day of week  
use method on page 5.  
Thermostat does not advance day  
of week.  
If problems with thermostats cannot be solved, call:  
Technical Support: 608-257-8801  
Monday-Friday 7:45 am-5:00 pm CST  
10  
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Wiring Diagrams  
The following is just a sample of the most common types of HVAC systems.  
Refer to your system’s installation manual for wiring information.  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO CARRIER  
SPLIT SYSTEM CONDENSORS AND HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
O
G
E
W2  
L
24 VAC, COMMON  
C
W3  
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO  
ROBERT SHAW 3000 SERIES HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [HEATING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
B
G
E
W2  
L
24 VAC, COMMON  
X
O
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
11  
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APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO COMFORTMAKER  
CYC SERIES HEAT PUMP SYSTEMS  
NOTE 1: E AND W2 TERMINALS  
JUMPERED AT THERMOSTAT  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
NOTE 2: W2 TERMINAL ON  
COMFORTMAKER PCB CAPPED  
NOTE 3: X TERMINAL ON  
COMFORTMAKER PCB CAPPED  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
Field  
Installed  
Jumper  
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
O
G
2ND. STAGE HEATING CIRCUIT  
OUTDOOR THERMOSTAT [CAPPED]  
DEFROST SENSOR [CAPPED]  
24 VAC, COMMON  
W1  
W2  
X
C
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO HEIL-QUAKER  
867.814 SERIES AND PH50 SERIES HEAT PUMP SYSTEMS  
NOTE 1: E AND W2 TERMINALS  
JUMPERED AT THERMOSTAT  
NOTE 2: W2 TERMINAL ON  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
HEIL-QUAKER PCB CAPPED  
Field  
Installed  
Jumper  
24 VAC, RETURN  
R
COMPRESSOR CONTACTOR  
Y
O
G
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
2ND. STAGE HEATING CIRCUIT [SEQUENCER 1]  
3RD. STAGE HEATING CIRCUIT [SEQUENCER 2]  
24 VAC, COMMON  
W1  
W2  
C
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
12  
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APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO PAYNE  
RELIANT AND ENDURA MODEL HEAT PUMP SYSTEMS  
NOTE 1: W3 TERMINAL ON  
PAYNE PCB CAPPED  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
Y2  
R
O
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
O
G
E
W2  
L
24 VAC, COMMON  
C
3RD. STAGE HEATING CIRCUIT [CAPPED]  
W3  
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO RHEEM/RUUD  
HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [HEATING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
B
G
E
W2  
L
24 VAC, COMMON  
X
B
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
13  
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APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION  
TO WEATHERTRON HEAT PUMPS  
NOTE 1: E AND W2 TERMINALS  
JUMPERED AT THERMOSTAT  
NOTE 2: X2 TERMINAL CAPPED AT  
WEATHERTRON PCB  
NOTE 3: T TERMINAL CAPPED AT  
WEATHERTRON PCB  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
Field  
Installed  
Jumper  
24 VAC, RETURN  
R
COMPRESSOR CONTACTOR  
Y
O
G
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
X2  
2ND. STAGE HEATING CIRCUIT  
24 VAC, COMMON  
W-U  
B
T
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO YORK  
-E1CS, -E1FB, -E1FH HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
NOTE 1: E AND W2 TERMINALS  
JUMPERED AT THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
Field  
Installed  
Jumper  
24 VAC, RETURN  
R
COMPRESSOR CONTACTOR  
Y
O
G
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
24 VAC, COMMON  
W
X
B
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
14  
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APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO LENNOX  
CB19 HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R
Y
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
O
G
E
W1  
L
24 VAC, COMMON  
C
T
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO LENNOX  
HP19 AND HP20 HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
V-VR  
M
R
F
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
E
Y
24 VAC, COMMON  
X
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
15  
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APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO LENNOX  
HP21 WITH CB21 PCB HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R-VR  
Y1  
O
REVERSING VALVE [COOLING MODE]  
FAN CONTACTOR CIRCUIT  
F
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
E
W1  
L
24 VAC, COMMON  
X
Y2  
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT CONVERSION TO LENNOX  
HP22 WITH CB19 PCB HEAT PUMP SYSTEMS  
APRILAIRE MODEL 8355 HEAT PUMP THERMOSTAT  
W2  
R
O
Y2  
Y1  
B
G
E
L
C
24 VAC, RETURN  
COMPRESSOR CONTACTOR  
R-VR  
M
R
F
REVERSING VALVE [HEATING MODE]  
FAN CONTACTOR CIRCUIT  
EMERGENCY HEATING CIRCUIT  
2ND. STAGE HEATING CIRCUIT  
SYSTEM MONITOR LED  
E
Y
L
24 VAC, COMMON  
X
2ND. STAGE COOLING CIRCUIT  
Y2  
THE LOW VOLTAGE TERMINAL DESIGNATIONS AND THEIR DESCRIPTION AND/OR  
FUNCTION ARE USED ON ALL SPLIT SYSTEM CONDENSORS AND HEAT PUMPS  
Limited Warranty  
Your Research Products Corporation Aprilaire® Thermostat unit is expressly warranted for two (2) years from date of installa-  
tion to be free from defects in materials and workmanship. Research Products Corporation’s exclusive obligation under this war-  
ranty shall be to supply, without charge, a replacement for any thermostat which is found to be defective within a two (2) year  
period and which is returned, together with the date of installation, no later than thirty (30) days after said two (2) year period  
by you to either your original supplier or to Research Products Corporation, Madison, Wisconsin 53701.  
THIS WARRANTY SHALL NOT OBLIGATE RESEARCH PRODUCTS CORPORATION FOR ANY LABOR COSTS AND SHALL NOT  
APPLY TO DEFECTS IN WORKMANSHIP OR MATERIALS FURNISHED BY YOUR INSTALLER AS CONTRASTED TO DEFECTS  
IN THE THERMOSTAT ITSELF.  
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE SHALL BE LIMITED IN DURA-  
TION TO THE AFORESAID TWO YEAR PERIOD. RESEARCH PRODUCTS CORPORATION’S LIABILITY FOR INCIDENTAL OR  
CONSEQUENTIAL DAMAGES, OTHER THAN DAMAGES FOR PERSONAL INJURIES, RESULTING FROM ANY BREACH OF THE  
AFORESAID IMPLIED WARRANTIES OR THE ABOVE LIMITED WARRANTY IS EXPRESSLY EXCLUDED. THIS LIMITED WAR-  
RANTY IS VOID IF DEFECT(S) RESULT FROM FAILURE TO HAVE THIS THERMOSTAT INSTALLED BY A QUALIFIED HEATING  
AND AIR CONDITIONING CONTRACTOR. IF THE LIMITED WARRANTY IS VOID DUE TO FAILURE TO USE A QUALIFIED CON-  
TRACTOR, ALL DISCLAIMERS OF IMPLIED WARRANTIES SHALL BE EFFECTIVE UPON INSTALLATION.  
Some states do not allow limitations on how long an implied warranty lasts or the exclusion or limitation of incidental or con-  
sequential damages, so the above exclusion or limitations may not apply to you. This warranty gives you specific legal rights  
and you may also have other rights which vary from state to state.  
P.O. BOX 1467 • MADISON, WI 53701-1467  
Products For Better Indoor Air Quality  
B2202518 REV. 12/00  
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