Honeywell CT70 User Manual - Free PDF Download

Page 3 - HOW TO USE THIS GUIDE

3 HOW TO USE THIS GUIDE Before you disconnect the wires and remove your existing thermostat, be sure this new thermostat, see the CT70 wiring hookup diagram, will replace it and that you understand how you will reconnect the wiring. To do that, proceed as follows: Step 1 Find the manufacturer of you...

Page 5 - TABLE OF CONTENTS

5 TABLE OF CONTENTS How to Use This Guide ................................................. 3 Heat Pumps are Different .............................................. 6 Heat Pumps are Two Systems in One .......................... 7 Definitions of Terminal Functions ............................... 8,9...

Page 6 - HEAT PUMPS ARE DIFFERENT; Heat pump systems

6 HEAT PUMPS ARE DIFFERENT Heat pump systems usually have a supplemental, Second Stage heating system that operates only when necessary. This heat pump thermostat is designed to minimize more expensive second- stage operation, indicated by the green AUX. HEAT light on your thermostat.

Page 7 - HEAT PUMPS ARE TWO SYSTEMS IN ONE; In mild weather, virtually all of the demand for heat in

7 HEAT PUMPS ARE TWO SYSTEMS IN ONE In mild weather, virtually all of the demand for heat in buildings can be met by the heat pump compressor. This First Stage process of moving heat indoors is very economical. As the air becomes colder outside, the first stage may be unable to deliver enough heat t...

Page 8 - DEFINITIONS OF TERMINAL FUNCTIONS; Function Definition

8 DEFINITIONS OF TERMINAL FUNCTIONS Each terminal of the CT70 controls a different heat pump function. Here is a list of the possible heat pump functions: Function Definition FIRST STG. HEAT: When this terminal is activated, the heat pump is on and heating the living space. AUXILIARY HEAT: When this...

Page 9 - OUTDOOR

9 FAN: When this terminal is activated, the fan is on. With the fan switch in the auto position, the fan cycles on and off with the heat pump. With the fan switch in the ON position, the fan is on continuously. MULTIPLE AUX. HEAT LOADS: This terminal is activated when additional auxiliary heat loads...

Page 10 - Typical wiring hookup of CT70 with jumper intact.

10 Typical wiring hookup of CT70 with jumper intact. M8504 W2 W1 X O E G Y1 R L B L1 (HOT) L2 1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED. REMOVE W1-Y1 JUMPER WHEN HEAT RELAY 1 IS USED. WHEN L TERMINAL IS CONNECTED TO SYSTEM MONITOR, EM. HEAT. LED ALSO INDICATES COMP...

Page 11 - AMANA

11 AMANA ! Jumper these two terminals if both are present # This terminal must be connected to transformer common. $ Remove this factory-installed jumper for independent stage 1 heat and cool connection. W1 Wiring terminal function Existing thermostat wiring New thermostat wiring COMMON POWER COMPRE...

Page 15 - CARRIER

15 CARRIER ! This terminal must be connected to transformer common. # Leave factory-installed jumper in place. Wiring terminal function Existing thermostat wiring New thermostat wiring COMMON POWER COMPRESSOR 1 ST STG. HEAT AUX. HEAT FAN C/O VALVE HEAT C/O VALVE COOL SYSTEM MONITOR EM. HEAT C X R R ...

Page 16 - FRIEDRICH

16 FRIEDRICH ! This terminal must be connected to transformer common. # Leave factory-installed jumper in place. $ Tape off the end of the wire. Jumper is not required on this thermostat (CT70). Wiring terminal function Existing thermostat wiring New thermostat wiring COMMON POWER COMPRESSOR 1 ST ST...

Page 18 - LENNOX

18 LENNOX ! This terminal must be connected to transformer common. # Leave factory-installed jumper in place. R Wiring terminal function Existing thermostat wiring New thermostat wiring COMMON POWER 1 ST STG. HEAT (COMP) 1 ST STG. COOL 2 ND STG. HEAT FAN C/O VALVE HEAT C/O VALVE COOL SYSTEM MONITOR ...

Page 20 - TRANE/AMERICAN STANDARD

20 TRANE/AMERICAN STANDARD ! This terminal must be connected to transformer common. # Leave factory-installed jumper in place. $ Tape off end. CT70 replaces outdoor reset with improved zero droop performance. Wiring terminal function Existing thermostat wiring New thermostat wiring COMMON POWER 1 ST...

Page 24 - Automation and Control Solutions

69-0866—2 C.H. Rev. 01-95 www.honeywell.com/yourhome Automation and Control Solutions Honeywell International Inc.1985 Douglas Drive NorthGolden Valley, MN 55422