Robertshaw 9401 User manual

Application
The Robertshaw 9401 is a single-stage thermostat designed to control
24 VAC gas or electric heating and cooling systems or single-stage heat
pump. The 9401 requires the use of a common wire.
Features
•Summer and winter setpoints
•Large back lit display
•Adjustable temperature differential: .5°F to 3.0°F (0.5°C to 1.5°C)
•Compressor short cycle protection
•Accuracy within ±1°
•Zone system compatible as a master thermostat
•Permanent memory retention
•Fahrenheit/Celsius display option
•Adjustable from 45°F to 90°F (7°C - 32°C)
•Quick wire terminal block
•Automatic heating shutdown if temperature exceeds 94°F (34°C)
1
DIGITAL
NON-PROGRAMMABLE
THERMOSTAT
9401
ELECTRIC
E
GAS
G
OIL
O
®
NeW
1 Heat / 1 Cool
User's Manual
Quick Start
Installation
110-1041

IMPORTANT SAFETY INFORMATION
WARNING:
•Always turn off power at main fuse or circuit breaker panel before
installing, removing, cleaning, or servicing thermostat.
•Read all the information in this manual before installing this
thermostat.
•This is a 24 VAC low-voltage thermostat. Do not install on voltages
higher than 30 VAC.
•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.
•Do not connect ground to any terminal in this unit.
Step 1: Replacing Existing Thermostat
1. Turn off power to heating and cooling system.
2. Remove cover from old thermostat to expose wires (Figure 1).
3. Disconnect wires one at a time from existing terminals. Use enclosed labels
to mark existing wires. Refer to cross references in Table 1 if existing wiring
does not directly match the labels.
4. Remove existing thermostat base from wall.
Old Terminal New Label Description
M,W,Rh,R5 or 5 Rh Heat transformer, hot side
V or Rc Rc Cool transformer, hot side
C,X, or B C 24VAC transformer, common side
Y or Y6 Y Cooling control
H,W, or 4 W Heating control
F or G G Fan control relay
OOCool active reversing valve
BBHeat active reversing valve
NOTE: THIS THERMOSTAT REQUIRES A 24V AC COMMON WIRE FOR PROPER OPERATION.
Table 1
2
Figure 1
!

Recycling Thermostat
If this thermostat is replacing a thermostat that contains mercury
in a sealed tube, do not place your old thermostat in the garbage.
Contact your local waste management authority for instructions
regarding proper disposal of the thermostat. If you have any ques-
tions, call Robertshaw technical support at 1-800-445-8299.
Step 2: Installing Model 9401 Thermostat
NOTE: FOR NEW INSTALLATIONS, MOUNT THERMOSTAT ON
INSIDE WALL, FIVE 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
LOCATIONS WILL AFFECT THERMOSTAT OPERATION.
1. Turn power off to the heating and cooling systems.
2. Place HEAT-OFF-COOL in OFF position (Figure 2).
3. Place -ON-AUTO switch into AUTO position (Figure 2).
4. Remove the cover using a coin or screwdriver (Figure 3). Set aside.
3
Figure 3
SETTING OR CHANGING THE SETPOINT TEMPERATURE:
1. Press or button. Display will show SET and the current
temperature setpoint.
2. Press or button to adjust temperature setpoint.
3. After completing the change, the display will return to the current
room temperature after a few seconds.
CHANGING THE TEMPERATURE DIFFERENTIAL,
DEAD BAND, AND RESIDUAL COOL:
The temperature differentials are factory set at 1˚F and 2˚F for
1ST and 2ND stages respectively. The dead band for Auto-
changeover is set at 3˚F . Tochange settings:
1. Press the and buttons at the same time and hold for 1
second. Display will indicate: DIFFERENTIAL 1ST.
2. Press either the or button to adjust the 1st stage differ-
ential between 0.5˚F – 3˚F (0.5˚C - 1.5˚C).
3. Either wait five seconds or press the button. The display
will indicate: DIFFERENTIAL 2ND.
4. Press either the or button to adjust 2nd stage differen-
tial between 1˚F – 6˚F (1˚C - 3˚C).
5. Either wait five seconds or press the button. The display
will indicate: DEADBAND.
6. Press either the or button to adjust the dead band
between 3˚F – 6˚F (1.5˚C -3˚C).
7. Either wait five seconds or press the button. The fan
icon and ON will be displayed.
8. Press either the or button to adjust the Residual Cool
fan delay between 0, 30, 60, or 90 seconds.
9. The display will return to the current room temperature after
a few seconds.
Item
9555
120-1523
Maple Chase Company
www.maplechase.com
Tech Service: 1-800-445-8299
M-F 7:30 a.m. - 5:30 p.m. CST
MADE IN MEXICO
TM
Figure 2

5. Place thermostat against the wall at desired location. Make sure wires
will feed through opening (Figure 4) on base of thermostat.
6. Mark placement of mounting holes (Figure 4). Set base aside.
7. If mounting on drywall, tap plastic anchors into wall.
NOTE: ENCLOSED PLASTIC ANCHORS DO NOT REQUIRE A
DRILLED HOLE FOR DRYWALL.
8. If mounting on a surface other than drywall, drill the marked holes
using a 3/16" drill bit.
9. Align base with plastic anchors and feed wires through opening.
10. Secure base to wall with supplied screws.
NOTE: THE THERMOSTAT WILL MOUNT HORIZONTALLY
ON A SINGLE GANG JUNCTION BOX.
11. Strip end of wires 5/16” if needed.
12. Terminal screws are already loose and ready for wire insertion.
Insert wires into terminal strip (Figure 5) matching the label to the
corresponding terminal (see Wiring Diagrams). Tighten screws.
13. Make sure wire connections are secure.
14. Push excess wire back through opening.
4
RESET
NON-HP
Mounting Holes
Wiring Opening
HP
ELECGAS
Figure 4
W
Rh Rc C
Y
B
O
G
Label
Y
Figure 5

5
Hot
Heating
Control
Fan
Control
Cooling
Control
(COOLING)
Transformer
(HEATING)
Transformer
Transformer
T
H
E
R
M
O
S
T
A
T
T
H
E
R
M
O
S
T
A
T
RH
RC
W
Y
G
T
H
E
R
M
O
S
T
A
T
RH
RC
W
Y
G
C C
24 VAC
120 VAC
Hot
Heating
Control
Fan
Control
Transformer
24 VAC
120 VAC
T
H
E
R
M
O
S
T
A
T
RH
RC
W
Y
G
CC
RH
RC
W
Y
G
C
Hot
Heating
Control
Heating
Control
Transformer
24 VAC
24 VAC
24 VAC
120 VAC
Hot
120 VAC
Hot
120 VAC
HEAT / COOL
4-WIRE
SINGLE TRANSFORMER
HEAT ONLY
2-WIRE
SINGLE TRANSFORMER
HEAT ONLY
3-WIRE
SINGLE TRANSFORMER
Factory-Installed
jumper
Factory- Installed
jumper
T
H
E
R
M
O
S
T
A
T
RH
RC
W
Y
G
Hot
Cooling
Control
Fan
Control
Transformer
24 VAC
120 VAC
COOL ONLY
3-WIRE
SINGLE TRANSFORMER
HEAT / COOL
5-WIRE
TWO TRANSFORMER
NOTE: Both transformers
must be in phase.
Cooling
Control
Fan
Control
NOTE: Cut center of
factory installed jumper
and bend back
NOTE: Cut center of factory installed
jumper and bend back.
W
G
Hot
Fan
Relay
Transformer
24 VAC
120 VAC
HEAT PUMP WITH
HEAT ACTIVE
REVERSING VALVE
T
H
E
R
M
O
S
T
A
T
RH
RC
Y
O
B
C
Pre-Installed jumper
Compressor
Contactor
Reversing
Valve
Hot
Fan
Relay
Transformer
24 VAC
120 VAC
HEAT PUMP WITH
COOL ACTIVE
REVERSING VALVE
T
H
E
R
M
O
S
T
A
T
RH
RC
W
G
Y
O
B
C
Pre-Installed jumper
Compressor
Contactor
Reversing
Valve
◆Wiring Diagrams
NOTE: Installer must place jumper between
W and Y terminals. NOTE: Installer must place jumper between W and Y terminals.

15. Set the GAS/ELEC switch to either GAS for a gas/oil heating
system or ELEC for an electric heating system (Figure 6).
16. Set the HP/NON-HP switch to either the HP for heat pump or
NON-HP for furnace applications (Figure 6).
17. Replace thermostat cover by snapping into place.
6
RESET
NON-HP HP
ELECGAS
ROOM
OFF
NON-HP/HP
Switch
GAS/ELECTRIC
Switch
Figure 6
d
TERMINAL LEGEND - 9401
TERM EQUIPMENT TO CONNECT REQ? TERMINAL FUNCTION
Rh 24VAC hot connection Yes For input of 24VAC hot
side of heat transformer
Rc 24VAC hot connection Yes For input of 24VAC hot
side of cool transformer
C24VAC common connection Yes For input of 24VAC
common side of
transformer
WHeat connection Yes* Energizes on a call for
heating
YCompressor Connection Yes* Energizes on a call for
cooling
BHeat Active Reversing Valve No Energizes when in the
HEAT mode
OCool Active Reversing Valve No Energizes when in the
COOL mode
GIndoor fan connection Yes Energizes with Y & W
terminals in electric
mode; or with Y terminal
in gas mode; or with FAN
option switched to the
ON position
* This thermostat can be used as a heat only or cool only thermostat therefore it is not always
necessary to use both Y and W.

7
Step 3: Testing the 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.
1. Place the HEAT-OFF-COOL switch into
the COOL position. The display will read COOL.
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. The snowflake icon will be displayed.
NOTE: ONCE THE THERMOSTAT TURNS OFF WHEN IN THE COOL MODE,
A BUILT IN 5-MINUTE DELAY PREVENTS THE SYSTEM FROM
TURNING ON AGAIN. THIS PROTECTS THE COMPRESSOR. NO
ADDITIONAL TIME DELAY RELAY IS REQUIRED. TO OVERRIDE THE
5-MINUTE DELAY FOR INSTALLATION, PRESS THE RESET BUTTON.
3. Put the HEAT-OFF-COOL switch into
the OFF position. The air conditioning system
should turn off.
4. Put the HEAT-OFF-COOL switch into
the HEAT position. The display will read HEAT.
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 on the fan delay built into the furnace.
The flame icon will be displayed.
6. Put the HEAT-OFF-COOL switch into
the OFF position. The heating system should
turn off. The fan may continue to run for a
short period of time.
!

7. Put the -ON-AUTO switch into the ON
position. The blower fan should turn on.
The display will show a and ON.
8. Put the -ON-AUTO switch into the AUTO
position. The blower fan should turn off.
Step 4: Customizing the Thermostat
◆Settings
System
Cool: The thermostat controls the cooling.
Off: The heating and cooling systems are off.
Heat: The thermostat controls the heat.
Fan
Auto: Equipment controls the fan.
On: The fan operates continuously.
Temperature
Heating: The default temperature for heating is 70°F (21°C). To
change the default setpoint, put the system switch in HEAT and
press the or button to adjust the temperature setting up or
down. The display will show SET. The display will return to the
current room temperature three seconds after the last input and
the new setpoint will be saved.
Cooling: The default temperature for cooling is 78°F (25°C). To
change the default setpoint, put the system switch in COOL and
press the or button to adjust the temperature setting up or
down. The display will show SET. The display will return to the
current room temperature three seconds after the last input and
the new setpoint will be saved.
8
ROOM
OFF
Figure 7

9
◆Temperature Differential
The temperature differential is factory set at 1.0°F (.5°C). This means
that whenever the room temperature changes by one degree
Fahrenheit from the temperature setting, the system will turn on. If the
system turns on too often, increase the temperature differential.
◆Changing Fahrenheit (°F) to Celsius (°C),
and the Temperature Differential
1. The thermostat is preset to display the temperature in degrees
Fahrenheit (US models) or degrees Celsius (Canadian models). The
temperature display can be changed. Press and hold both the
and button for three seconds. The display will read F or C.
Release buttons. Press the or button to switch the display.
2. After three seconds the display will switch to the differential set-
tings. The display will read SET DIFF.
3. The temperature differential is factory set at 1.0°F (0.5°C). Press the
or button to adjust the differential up or down.
4. Wait three seconds or press and the display will return to the
original room temperature.
◆Backlit Display
This thermostat is equipped with a backlight to make nighttime temper-
ature adjustments quick and easy. Press the button to activate the
backlight. The backlight will turn off after about 5 seconds of inactivity.
◆Reset
To reset the thermostat press the RESET button located at the lower left
corner of the base.
RESET
RESET Switch
NON-HP HP
ELECGAS
ROOM
OFF

Step 5: Troubleshooting
Symptom Remedy
Thermostat does not turn on system. Check wiring (see Installation
section).
If problems with thermostat cannot be resolved, call:
Technical Support: [phone]
Monday-Friday 7:30 AM - 5:30 PM CST
10
Thermostat turns system on and
off too frequently. Increase temperature differential
(see Changing the Temperature
Differential section).
System fan does not operate
properly.
Move fan option switch to either
gas or electric, to match system
(see Installation section).
Thermostat does not display
proper room temperature. Check F/C (Fahrenheit/Celsius)
setting. See Changing Fahrenheit
(F) to Celsius (C).