background image

PRODUCT DATA

® U.S. Registered Trademark
Copyright © 1997 Honeywell Inc.   •            •   All Rights Reserved

T8501 and T8511

Deluxe Electronic Thermostats

APPLICATION

The T8501 and T8511 Deluxe Electronic Thermostats provide
electronic control of 18 to 30 Vac single stage or multistage
heating and cooling systems, including heat pump systems.

T8501/T8511
FEATURES AND BENEFITS

Attractive styling complements any decor to the
homeowner’s delight.

Ease-of-use means fewer homeowner questions and
increased homeowner satisfaction.

Back lighting the large display makes the Liquid
Crystal Display (LCD) very easy to read.

Most frequently used keys are located by the LCD for
quick and easy access to information.

Models available with outdoor temperature sensor
capability for homeowner convenience. The sensor is
also more accurate than a thermometer.

Configurable features allows one model to be used to
replace many different models (less inventory, no
need to carry separate models to get these features).

°

F or 

°

C temperature display;

Automatic or manual changeover;

Electric or conventional heat fan operation;

Adjustable heating cycle rate.

Minimum off time for cooling compressors and heat
pumps protects and extends the life of the equipment.

Easy installation, setup and system test saves
installer time and increases productivity.

System test simplifies troubleshooting and saves time
by overriding the time delays.

Setpoints are permanently held in memory (no
batteries used) and retained during power outages for
increased installer and homeowner convenience.

Contents

Application ........................................................................... 1
T8501/T8511 Features and Benefits ...................................

1

Specifications ......................................................................

2

Ordering Information ...........................................................

2

Installation ........................................................................... 3
Wiring .................................................................................. 4
Settings ...............................................................................

6

Installer Setup .....................................................................

6

Installer System Test ...........................................................

8

Checkout ............................................................................. 10
Operation ............................................................................ 11
Wiring Diagrams (Fig. 13-18) .............................................. 12
Troubleshooting Guide ........................................................ 14

68-0162-1

Summary of Contents for T8501

Page 1: ...ccurate than a thermometer Configurable features allows one model to be used to replace many different models less inventory no need to carry separate models to get these features F or C temperature display Automatic or manual changeover Electric or conventional heat fan operation Adjustable heating cycle rate Minimum off time for cooling compressors and heat pumps protects and extends the life of...

Page 2: ...ications Also This product is tested and calibrated under closely controlled conditions and some minor differences in performance can be expected if those conditions are changed Models See Table 1 Electrical Rating Input Power 18 to 30 Vac 50 60 Hz Load Rating See Table 2 Temperature Setpoint Range 40 F to 99 F 4 C to 37 C depending on model and if in heating or cooling Display Range Controlled 30...

Page 3: ...the product or cause a hazardous condition 2 Check the ratings given in the instructions and on the product to make sure the product is suitable for your application 3 Installer must be a trained experienced service technician 4 After completing installation use these instructions to checkout the product operation CAUTION Disconnect power supply to prevent electrical shock or equipment damage Loca...

Page 4: ...T Outdoor temperature sensor input for C7089B Input R V 24V system transformer Input RC 24V cooling transformer Input RH V 24V heating transformer Input W Heating relay Output 24V powered contact W1 H1 R3 Heating relay Output 24V powered contact W2 H2 R4 W3 Y Stage 2 heating relay or auxiliary heat relay Output 24V powered contact X1 A1 A C L X Z User defined Light Emitting Diodes LEDs Annunciatio...

Page 5: ...rmostat Fig 4 Proper wiring technique Mounting Thermostat 1 Engage tabs at the top of thermostat and wallplate See Fig 5 2 Press lower edge of case to latch NOTE To remove the thermostat from the wall first pull out at the bottom of the thermostat remove top last M6798A B PRESS LOWER EDGE OF CASE TO LATCH A ENGAGE TABS AT TOP OF THERMOSTAT AND WALLPLATE Fig 5 Mounting thermostat on wallplate Using...

Page 6: ...ostat factory settings will not need to be changed Review the factory settings in Table 4 and if no changes are necessary go to the Installer System Test section The Installer Setup is used to customize the thermostat to specific systems Installer Setup numbers are listed in Table 4 The table includes all the configuration options available A combination of key presses are required to use the Inst...

Page 7: ...ed fan operation in heatinga b 19 00 No extended fan operation after the call for heat ends 01 Fan operation is extended 90 seconds after the call for heat ends Extended fan operation in coolingb 20 00 No extended fan operation after the call for cool ends 01 Fan operation is extended 90 seconds after the call for cool ends Not used 21 thru 23 Outdoor temperature displayb 24 00 No outdoor tempera ...

Page 8: ...system test The system test will time out after five minutes without any key presses Press and hold the increase and decrease keys at the same time until two zeros appear All segments of the display will be displayed before the two zeros appear See Fig 10 and 11 M6792A TEST NUMBER Installer Setup Number Press i key Factory Setting Other Choices Press or key to change Actual Select to change Displa...

Page 9: ...pment system test 41 Fan comes on 40 Fan turns off Key or Switch Operation System Test IMPORTANT Test numbers will only be displayed when the system is configured for the selected function EXAMPLE Numbers 60 61 and 62 are the only numbers that will be displayed when a system is configured for heat only SYSTEM KEY SYSTEM TEST i 60 Change from cooling or fan to key operation system test System 61 He...

Page 10: ...ature is displayed to exit the system test The system test times out after five minutes without any key presses CHECKOUT Outdoor Temperature Sensor where applicable Allow the outdoor temperature sensor to soak in the outdoor air for a minimum of five minutes before taking a reading With an accurate thermometer 1 F 0 5 C measure the temperature at the sensor location allowing time for the thermomet...

Page 11: ...energy savings Occupants do not need to continually adjust thermostat settings to maintain desired temperature even during severe weather Operation Sequence The thermostat energizes specific terminals depending what the Fan and System are set to The LCD will display symbols and words to report the condition of system See Tables 7 and 8 for specific information Table 7 T8501 Sequence of Operation F...

Page 12: ...set for electric heat systems the fan comes on at the same time as the heat and is energized by the thermostat The fan is energized by the plenum switch when set for conventional heating system Outdoor Temperature Sensor select models The outdoor temperature sensor is used to display the outdoor temperature Pressing the Information i key once will show the outdoor temperature if Installer Setup nu...

Page 13: ...wiring between thermostat and HVAC equipment replace any broken wires and tighten any loose connections If 24 Vac is present proceed with troubleshooting Temperature display is incorrect Room temperature display has been reconfigured Enter Installer Setup number 37 and reconfigure the display Thermostat is configured for F or C display select models Enter Installer Setup number 14 and reconfigure ...

Page 14: ...e circuit breaker is tripped reset the circuit breaker check if the system fuse is blown replace the fuse check if the system switch at the equipment is in the Off position set to the On position check wiring between thermostat and HVAC equipment replace any broken wires and tighten any loose connections If 24 Vac is present proceed with troubleshooting Thermostat minimum off time is activated Wai...

Page 15: ...T8501 AND T8511 DELUXE ELECTRONIC THERMOSTATS 68 0162 1 15 ...

Page 16: ...rol Honeywell Limited Honeywell Limitée 155 Gordon Baker Road North York Ontario M2H 3N7 Honeywell Latin American Region 480 Sawgrass Corporate Parkway Suite 200 Sunrise FL 33325 Helping You Control Your World 68 0162 1 J H Rev 10 97 Printed in U S A Home and Building Control Honeywell Inc Honeywell Plaza P O Box 524 Minneapolis MN 55408 0524 Printed on recycled paper containing at least 10 post c...

Reviews: