Home

href="
CONTENTS  
WHITE-RODGERS  
Preparations........................................... 1  
Thermostat Features.............................. 2  
Removing Old Thermostat ..................... 3  
Mounting and Wiring .............................. 4  
Set Heat Anticipator ............................... 5  
New Thermostat Operation .................... 6  
Specifications ......................................... 7  
Troubleshooting ..................................... 8  
FA  
AU  
TO  
N
SYSTEM  
OFF  
ON  
COOL  
Installation Instructions for  
HEA  
T
Heating & Cooling  
90  
80  
70  
90  
Model 350  
60  
50  
80  
70  
60  
50  
PREPARATIONS  
YOUR THERMOSTAT REPLACES  
1
Assemble tools required as shown below.  
Description  
350  
Standard Heat & Cooling Systems – 4 or 5 wires  
Standard Heat Only Systems  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
No  
FLAT BLADE SCREWDRIVER  
WIRE CUTTER/STRIPPER  
Millivolt Heat Only Systems – Floor or Wall Furnaces  
Standard Central Air Conditioning  
HAND OR POWER  
DRILL WITH 3/16 INCH  
DRILL BIT, IF NEEDED  
Gas or Oil Heat  
Electric Furnace  
SPIRIT LEVEL OR PLUMB BOB AND LINE—  
THERMOSTAT MUST BE LEVEL TO WORK PROPERLY  
Hydronic (Hot Water) Zone Heat – 2 Wires  
Hydronic (Hot Water) Zone Heat – 3 Wires  
Heat Pump (No Aux or Emergency Heat)  
Heat Pump (with Aux or Emergency Heat)  
Baseboard Electric Heating or Line Voltage (120 or 240 volt)  
Yes  
No  
Failure to follow and read all instructions carefully be-  
fore installing or operating this control could cause  
personal injury and/or property damage  
No  
THERMOSTAT FEATURES  
REMOVING OLD THERMOSTAT  
2
3
CAUTION  
!
To prevent electrical shock and/or equipment damage,  
disconnect electrical power to the system at the main  
fuse or circuit breaker until installation is complete.  
SWITCHING  
SUBBASE  
KEEP THIS AREA  
CLEAR OF WIRES  
Before removing wires from old thermostat’s switching subbase,  
label each wire with the terminal designation it was removed from.  
1. Remove Old Thermostat: A standard heat/cool thermostat  
ANTICIPATOR  
consists of three basic parts:  
MOUNTING  
SCREWS  
a. The cover, which may be either a snap-on or hinge type.  
b. The base, which is removed by loosening all captive screws.  
c. The switching subbase, which is removed by unscrewing  
themountingscrewsthatholditonthewalloradaptorplate.  
MOUNTING  
SCREWS  
BASE  
Make a note here  
of the anticipator setting on  
the old thermostat for future reference and use in step 5.  
The heat anticipator pointer, if adjustable, will be set at one of a  
series of numbers representing the current rating of the primary  
control in your furnace. The number will be one of the following:  
.2, .4, .8, etc. or 0.2, 0.4, 0.8, etc.  
If no heat anticipator/indication is showing, do not be concerned;  
move on to the next step.  
COVER  
Figure 1.  
WHITE-RODGERS  
EMERSON ELECTRIC CO.  
9797 REAVIS ROAD  
PART NO. 37-6237A  
Printed in U.S.A.  
ST. LOUIS, MISSOURI 63123-5398  
0116  
href="
REMOVING OLD THERMOSTAT  
3
4
CAUTION  
Take care when securing and routing wires so they do  
not short to adjacent terminals or rear of thermostat.  
Personal injury and/or property damage may occur.  
!
CONTINUED FROM FIRST PAGE  
ATTENTION! This product contains mercury. There will not be  
any exposure to mercury under normal conditions of use. This  
product may replace a unit which contains mercury.  
Do not open mercury cells. If a cell becomes damaged, do not  
touch any spilled mercury. Wearing non-absorbent gloves, take  
up the spilled mercury and place into a container which can be  
sealed. If a cell becomes damaged, the unit should be disgarded.  
TERMINAL CROSS REFERENCE CHART  
New Thermostat  
Other Manufacturers’  
Terminal Designation  
Terminal Designation  
*
*
Mercury must not be discarded in household trash. When the unit  
this product is replacing is to be discarded, place in a suitable  
container and return to White-Rodgers at 9797 Reavis Road, St.  
Louis, MO, 63123-5398 for proper disposal.  
RH  
RC  
G
4
R
G
W
Y
RH  
R
M
V
F
R5  
-
R
-
G
G
4
G
W
Y
W
W
Y
H
C
MOUNTING AND WIRING  
Y
Y6  
* These are four-wire, single-transformer systems.  
Factory installed jumper wire between the RH  
and RC terminals must remain in place.  
WARNING  
!
Do not use on circuits exceeding specified voltage.  
Higher voltage will damage control and could cause  
shock or fire hazard.  
it to the A terminal. This will allow the thermostat to energize  
the fan immediately on a call for heat. If you are unsure if the  
heating system requires the thermostat to control the fan,  
contactaqualifiedheatingandairconditioningserviceperson.  
For single stage heat pump applications (no auxillary heat),  
install a short jumper wire (not included) across terminals  
W and Y. If the system has a reversing valve connection  
energized in Cooling, attach it to O. If the system has a  
reversing valve connection energized in Heating, attach it to B  
(see Fig. 4). This thermostat will not provide multi-stage  
heating or cooling.  
Do not short out terminals on gas valve or primary  
control to test. Short or incorrect wiring will damage  
thermostat and could cause personal injury and/or  
property damage.  
Thermostat installation and all components of the sys-  
tem shall conform to Class II circuits per the NEC code.  
Model 350 (Heating and Cooling):  
A. Remove base from subbase: Loosen the three screws on  
the base and remove.  
B. Mountswitchingsubbase:Usethescrewsprovidedtomount  
the subbase to wall (see Fig. 1).  
C. Attach wires to appropriate terminals:  
D. Mount Thermostat Base: Gently push excess wire back into  
the wall opening and plug hole with a fire-resistant material,  
such as fiberglass insulation to prevent drafts from affecting  
thermostat operation. Mount the thermostat base to the sub-  
base using the three captive screws on the thermostat base.  
(see Fig. 1) Tighten the screws securely. Proceed to Step #5.  
• For two wire systems (Heat Only or Cool Only). If you  
have a two-wire Heat Only system, attach one wire to RH and  
onetowireW.Ifyouhaveatwo-wireCoolOnlysystem,attach  
one wire to RC and one to wire to Y. Leave the factory  
installed jumper between RC and RH attached. Tighten any  
unused terminals securely.  
Factory-Installed Jumper  
RH  
W
B
O
Y
G
RC  
A
Heat  
Relay  
Compressor  
Relay  
Fan  
Relay  
Hot  
24 VAC  
120 VAC  
• If your system has more than two wires: Use the cross  
reference chart to determine correct wire connections. If you  
have a four-wire heat/cool system leave the factory installed  
jumper between RC and RH attached (see Fig 2.). If your  
system has five wires remove the factory installed jumper  
between RC and RH (see Fig 3.).  
Neutral  
TRANSFORMER  
Figure 2. Typical wiring for single transformer  
heating/cooling system  
RH  
W
B
A
O
Y
G
RC  
• Electric heat or single stage heat pump systems: This  
thermostat is configured from the factory to operate a heat/  
cool, fossilfuel(gas, oil, etc.)forcedairsystem. Itisconfigured  
correctly for any system that DOES NOT require the thermo-  
stat to energize the fan on a call for heat. If your system is an  
electric heat or heat-pump system that REQUIRES the ther-  
mostat to turn on the fan on a call for heat, remove the yellow  
factory-installed jumper wire from the Y terminal and connect  
TRANSFORMER  
Hot  
TRANSFORMER  
Hot  
Heat  
Compressor  
Relay  
Fan  
Relay  
Relay  
24 VAC  
24 VAC  
120 VAC  
Neutral  
120 VAC  
Neutral  
Figure 3. Typical wiring for two-transformer  
heating/cooling system  
Factory-Installed Jumper  
Field-Installed Jumper  
RC  
G
RH  
O
W
Y
B
A
TRANSFORMER  
Hot  
Fan  
Relay  
Compressor  
Relay  
*
* *  
24 VAC  
120 VAC  
Neutral  
Terminal energized  
in cooling  
Terminal energized  
in heating  
*
* *  
Figure 4. Typical wiring for single transformer,  
single stage heat pump system  
href="
SET HEAT ANTICIPATOR  
5
Set anticipator to match the setting of your old thermostat you  
noted in Step 3, or, the anticipator should be set to match the  
current rating stamped on your main heating control. The heat  
anticipator is adjustable from 0.15 to 1.2 amps. Adjust the antici-  
pator by rotating the contact arm (see fig. 5). The anticipator  
setting is indicated by the numbers on the base that the pointer  
points to. If you are unsure where to set the anticipator contact the  
heater manufacturer for a recommended setting.  
.25  
.3  
.4  
.2  
.5  
.18  
.6  
.8  
Movethepointercounterclockwisetolengthen heatingsystem  
cycles; move clockwise to shorten heating cycles. Adjustments  
should not be greater than 1/2 marking at a time.  
.15  
1.  
Move this lever to  
adjust heat  
Arrow points to the  
current rating of the  
primary control  
anticipator  
Snap on Cover: Carefully align the cover with the base and snap  
the cover onto the base.  
Figure 5. Anticipator adjustment  
Typical Gas Valve  
Typical Zone Valve  
Typical Oil Primary  
24VAC  
50/60 Hz  
.43 Amps  
24VAC  
50/60 Hz  
.23 Amps  
24VAC  
50/60 Hz  
.35 Amps  
NEW THERMOSTAT OPERATION  
Shows switch position  
6
FAN  
SYSTEM  
This thermostat is easy to operate. Fig. 6 shows how the heating/  
cooling system and fan operate when the switches are in various  
positions. Use the system switch to select either heating or  
cooling, or to turn the heating/cooling system off. Use the fan  
switch to control fan operation. When the fan switch is in the  
AUTO position, the fan will cycle with the heating or cooling  
system (the fan will not run if the system switch is in the OFF  
position and the fan switch is in the AUTO position). When the fan  
switch is in the ON position, the fan will run continuously, regard-  
less of system switch position (even if the system switch is set to  
OFF, the fan will run if the fan switch is in the ON position).  
OPERATION  
AUTO ON  
COOL OFF HEAT  
No heating; no cooling; no fan  
No heating; no cooling; fan runs continuously  
Cooling system cycles from thermostat; fan runs  
continuously  
Cooling system and fan cycle from thermostat  
Heating system cycles from thermostat; fan cycles  
from fan control on furnace  
Heating system cycles from thermostat; fan runs  
continuously  
Figure 6. Subbase switching and thermostat/system operation  
SPECIFICATIONS  
7
THERMAL DATA:  
ELECTRICAL DATA  
Temperature Range ..............50°F to 90°F (10°C to 32°C)  
Operating Humidity Range...0 – 90% noncondensing  
Switch Rating ........................24 VAC (30 VAC max.)  
Heating ....................................0.15 to 1.2 Amps  
Cooling ....................................0 to 1.5 Amps  
Switch Action ........................SPST – Sealed mercury switch  
Anticipator Rating:  
Heating ....................................Adjustable from 0.15 to 1.2 Amps  
Cooling ....................................Fixed  
href="
TROUBLESHOOTING  
8
Symptom  
Possible Cause  
Corrective Action  
No Heat/No Cool/No Fan  
(common problems)  
1. Blown fuse or tripped circuit breaker.  
2. Furnace power switch to OFF.  
Replace fuse or reset breaker.  
Turn switch to ON.  
3. Furnace blower compartment door or  
panel loose or not properly installed.  
Replace door panel in proper position to engage  
safety interlock or door switch.  
No Heat  
1. Pilot light not lit.  
Re-light pilot.  
2. Broken or melted anticipator wire.  
Excessive current or dead short in system. Have  
a qualified service person check the system  
before replacing thermostat.  
3. Loose connection to thermostat or system.  
Verify thermostat and system wires are securely  
attached.  
4. Thermostat or heating system requires  
replacement or service.  
Your furnace manufacturer or service person can  
describe how to test the heating system to verify  
it is operating correctly. If the heating system is  
capable of operation and the no heat condition  
persists, replace the thermostat.  
5. System Switch not set to Heat.  
1. Furnace Lock-Out Condition  
Set System Switch to Heat and raise temp above  
room temp.  
Intermittent Heat  
No Cool  
Many furnaces have safety devices that shut the  
system down when a lock-out condition occurs. If  
the heat works intermittently contact the furnace  
manufacturer or local service person for assistance.  
1. Loose connection to thermostat or system.  
Verify thermostat and system wires are securely  
attached.  
2. Thermostat or cooling system requires  
replacement or service.  
Your cooling system manufacturer or service  
person can describe how to test the cooling  
system to verify it is operating correctly. If the  
cooling system is capable of operation and the no  
cooling condition persists, replace the thermostat.  
3. System Switch not set to Cool.  
Set System Switch to Cool and lower temp below  
room temp.  
Heat, Cool or Fan Runs Constantly.  
1. Possible short in wiring.  
2. Possible short in thermostat.  
3. Possible short in heat/cool/fan system.  
Check each wire connection to the thermostat to  
verify it is neatly looped under the terminals. No  
extra wire should stick out from under the  
terminals. As an added layer of insulation put a  
piece of electricians tape across the terminals on  
the subbase.  
Furnace Cycles Too Fast or Too Slow  
Narrow or wide temperature swing  
See Step 5, Adjusting the Anticipator.  
The anticipation setting is the only adjustment that  
effects the heating cycle rate. If an acceptable  
cycle rate is not achieved using the anticipator  
contact a local service person for additional  
suggestions. The location of the thermostat, size  
of the Heat/Cool System and current draw can  
influence the cycle rate.  
Cooling Cycles Too Fast or Too Slow  
(narrow or wide temperature swing)  
1. Poor thermostat location for sensing room  
temperature.  
2. Cooling system over or undersized.  
3. Excessive Current draw influencing thermostat.  
The cycle rate for cooling can not be adjusted.  
The location of the thermostat, size of the Cool  
system and current draw can influence the cycle  
rate. Contact a local service person for suggestions.  
Thermostat Setting and Thermostat  
Thermometer Disagree  
1. Thermostat thermometer setting requires  
adjustment.  
The thermometer can be adjusted by using a  
standard slotted screwdriver. Turn the thermom-  
2. Thermostat setting lever requires calibration. eter pointer screw located inside the front cover  
to change the setting. For calibrating the setting  
lever contact a local heating and cooling service  
person.  
Adjusting Thermometer  
1. Thermostat thermometer disagrees with  
other room thermometers.  
The thermometer on the thermostat is accurately  
calibrated at our factory but you can adjusted it  
by using a standard slotted screwdriver. Turn the  
thermometer pointer screw located inside the  
front cover to change the setting.