Robertshaw 9550 User manual

Application
The Robertshaw 9550 is a single-stage auto changeover thermostat
designed to control 24 VAC gas or electric heating and cooling systems or
single-stage heat pump. The 9550 requires the use of a common wire.
Features
•Auto changeover [deadband adjustable from 2°F to 8°F (1.0°C - 4.5°C)]
•Large back lit display
•Adjustable temperature differential
•Compressor short cycle protection
•Adjustable fan delay on cooling
•LED indication of system status
•Zone system compatible as a master thermostat
•Battery-free EEPROM memory retention
•Optional temperature limiting settings
•Fahrenheit/Celsius display option
•Gas/electric operation
•Adjustable from 45°F to 90°F (7°C - 32°C)
•Quick wire terminal block
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DELUXE
NON-PROGRAMMABLE
THERMOSTAT
9550
ELECTRIC
E
HEAT PUMP
H
GAS
G
®
NeW 1 Heat / 1 Cool
with Auto Changeover
User's Manual
Quick Start
Installation
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110-1034

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Figure 1
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 the information in this manual before installing or program-
ming 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.
Step 1: Replacing Existing Thermostat
1. Turn off power to heating and cooling system.
2. Removecoverfromoldthermostattoexposewires (Figure 1).
3. Disconnectwiresoneatatimefromexistingterminals.Useenclosedlabels
tomarkexistingwires.RefertocrossreferencesinTable1ifexistingwiring
doesnotdirectlymatchthelabels.
Old Terminal New Label Description
R, V-VR or VR-R R 24 VAC, Return
Y, Y1 or M Y Cooling Control
O or R O Cool Active Reversing Valve
BBHeat Active Reversing Valve
F or G G Fan Control Relay
C, X or B C 24 VAC, Transformer Common Side
W1 or W W Heating Control
NOTE: THIS THERMOSTAT REQUIRES A 24V COMMON WIRE FOR PROPER OPERATION.
Table 1
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•If you have any questions about cross referencing the old terminal to
the new label, reference your equipment installation manual, a
licensed contractor, or call Robertshaw Technical Support at
[phone].
4. Remove existing thermostat base from wall.
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 9550 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 AUTO-HEAT-OFF-COOL in OFF position (Figure 2).
3. Place -ON-AUTO switch into AUTO position (Figure 2).
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Figure 2
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. To change 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

4. Removethecoverusingacoinorscrewdriver(Figure3).Setaside.
5. Placethermostatagainstthewallatdesiredlocation.Makesurewires
willfeedthroughopening (Figure4)onbaseofthermostat.
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. Drill the marked holes using a 3/16" drill bit if mounting on a sur-
face other than drywall.
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.
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Figure 3
Mounting Holes
WIRING
OPENING
WYBOG
NON HP
Figure 4

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 below). Tighten
screws.
13. Make sure wire connections are secure.
14. Push access wire back through opening.
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WBG
W
Figure 5
Wiring Diagrams for 9550

15. If using a single stage heat pump system, set switch to HP.
16. Set the GAS/ELEC switch to either GAS for a gas/oil heating
system or ELEC for an electric heating system.
17. A temperature limiting jumper has been included in this thermo-
stat. Cutting this jumper (J3) limits the heating setpoint to no
greater than 72°F and the cooling setpoint to no lower than 78°F
(Figure 7).
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Heat Pump
Switch
GAS/ELECTRIC
Switch
WYBOG
J3
NON HP
Figure 6
TERMINAL LEGEND - 9550
TERM EQUIPMENT TO CONNECT REQ? TERMINAL FUNCTION
C24VAC common connection Yes For input of 24VAC common
side of transformer
R24VAC hot connection Yes For input of 24VAC hot side
of transformer
WFirst stage heat connection Yes* Energizes on a call for
heat
YSecond stage heat connection No Energizes on a call for
cooling
GIndoor fan connection Yes** Energizes with W (ELECTRIC
mode only) and Y or with
FAN option switched to the
ON position
OCool active reversing valve No*** Energizes when in the
connection COOL mode
BHeat active reversing valve No*** Energizes when in the
connection HEAT or EM modes
*This thermostat can be used as a heat only or cool only thermostat therefore it is not always
necessary to use both W and Y.
** A heat only gas system typically will not require the G terminal connection unless a separate
indoor blower is installed.
***Most heat pump systems will have a cool active OR a heat active reversing valve. Use the
appropriate terminal.

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18. Replace thermostat cover by snapping into place.
19. Turn on power to system. Test thermostat as described in the fol-
lowing section.
Step 3: Testing the Thermostat
WARNING: DO NOT SHORT (JUMPER) ACROSS TERMINALS OF
GAS VALVE OR SYSTEM CONTROL TO TEST OPER-
ATION. 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 CONDITION-
ING SYSTEM AND CAUSE PERSONAL INJURY.
1. Place the AUTO-HEAT-OFF-COOL 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: ONCE THE THERMOSTAT TURNS OFF WHEN IN THE COOL MODE, A
BUILT IN 5-MINUTE DELAY PREVENTS THE SYSTEM FROM TURN-
ING ON AGAIN. THIS PROTECTS THE COMPRESSOR. NO ADDI-
TIONAL TIME DELAY RELAY IS REQUIRED. TO OVERRIDE THE 5-
MINUTE DELAY FOR INSTALLATION, PRESS THE RESET BUTTON.
Cut the J3 jumper
to enable
temperature limiting
WYBOG
NON HP
Figure 7
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3. Put the AUTO-HEAT-OFF-COOL switch into
the OFF position. The air conditioning system
should turn off.
4. Put the AUTO-HEAT-OFF-COOL 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 on the fan delay built into the furnace.
6. Put the AUTO-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.
8. Put the -ON-AUTO switch into the AUTO
position. The blower fan should turn off.
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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.
AUTO:The thermostat automatically selects heat or cool depending
on the temperature.
Fan
Auto:Equipment controls the fan.
On: The fan operates continuously.
Temperature
The default setpoint temperature for heating is 70°F (21°C), for cool-
ing is 78°F (25°C), and for auto is 72°F (22.0°C). After putting the sys-
tem switch in heat, cool, or auto, press either the or button to
adjust the temperature setting up or down.
The display will return to the current room temperature five seconds after
the last input and the new setpoint will be saved.
◆Temperature Differential and Deadband
The temperature differential is factory set at 1°F (0.5°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.
Although programmed at the same time as the temperature differen-
tials, the deadband is used only during the AUTO mode. In the AUTO
mode, the thermostat will automatically cycle either the heating or cool-
ing system to maintain optimal comfort. The deadband is the minimum
allowable temperature which must occur to switch to the opposite
mode. For example, if the deadband is set at 3°F (1.5°C)and the setpoint
is set at 70°F, the thermostat will switch to cooling mode when the tem-
perature reaches 73°F.
NOTE: IF THE TEMPERATURE LIMITING JUMPER J3 IS CUT
(FIGURE 7), THE DEADBAND IS NOT ADJUSTABLE AND IS
AUTOMATICALLY SET TO 6°F (3°C).
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◆Changing Fahrenheit (F) to Celsius (C),
Temperature Differential, Deadband,
and Residual Cool
The temperature differential is factory set at 1°F (0.5°C). The deadband for
auto changeover is set at 3°F (1.5°C). To change settings:
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.
2. Press and hold both the and buttons for three seconds. The
display will read F or C. Release the buttons. Press the or but-
ton to switch the display.
3. After three seconds the display will switch to the differential setting.
The display will read DIFFERENTIAL 1st.
4. The temperature differential is factory set at 1°F (0.5°C). Press the
or to adjust the differential up or down.
5. Either wait three seconds or press the button. The display will
indicate: AUTOCHANGE DEADBAND.
6. Press either the or button to adjust the deadband between
2.0°F - 8.0°F (1.0°C - 4.5°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 original room temperature display after
a few seconds.
◆LED Indicators
The Robertshaw 9550 uses three LED indicators (in addition to icons
on the LCD display) to indicate functionality of the thermostat. When
illuminated, the right orange LED indicates that the thermostat is calling
for heat. The left green LED indicates a call for cool. The middle amber
LED indicates the fan is running.