Page 2 - do not disconnect the wires
CT87A,B,J ROUND® THERMOSTAT 69-0274-6 2 Prepare for installation 1. Carefully unpack your new thermostat; rough handling may affect its accuracy. Save your receipt and identify the following parts: • CT87 Thermostat • Screws: two 1-in. sheet metal screws, two 1/2-in. binding head screws, and two 1/4...
Page 3 - stat; Install the cover ring and wallplate or subbase; If installing on the wall; MERCURY NOTICE
CT87A,B,J ROUND® THERMOSTAT 3 69-0274-6 5. Label the wires using the wiring labels that came with the CT87. Identify each wire using the letter of the terminal on the old thermo- stat (Fig. 2). Do not label the wires by color. 6. Disconnect the wires from the old thermostat and wrap them around a pe...
Page 4 - If installing on an outlet box
CT87A,B,J ROUND® THERMOSTAT 69-0274-6 4 1. If using the cover ring: Position the cover ring against the wall so that the arrow in the middle of the cover ring is pointing up. 2. Position the wallplate or subbase. • If using cover ring: Place the wallplate/subbase over the cover ring. Rotate the wall...
Page 5 - Level the wallplate or subbase; IMPORTANT
CT87A,B,J ROUND® THERMOSTAT 5 69-0274-6 1. Place the cover ring against the outlet box so that the arrow in the middle of the cover ring is pointing up. 2. Pull the wires through the wiring hole on the bottom left side of the cover ring. 3. Align the screw slots on the cover ring with the outlet box...
Page 6 - Wire the thermostat; Wiring Cross-reference; Wire Label
CT87A,B,J ROUND® THERMOSTAT 69-0274-6 6 Wire the thermostat 1. Use the wiring cross-reference table below to match each old thermostat wire with its corresponding terminal on the CT87 wallplate or subbase. See Fig. 8 through 13 wiring diagrams. *Never attach wires to both the B and O terminals. 2. S...
Page 10 - Set the heat anticipator for your system; Setting the heat anticipator allows the thermostat to; Check heating/cooling operation; Check heating; Heat anticipator setting:
CT87A,B,J ROUND® THERMOSTAT 69-0274-6 10 Set the heat anticipator for your system IMPORTANT: Setting the heat anticipator allows the thermostat to maintain accurate temperature control. 1. Using a pencil point, move the heat anticipator pointer to the number that you recorded in Step 3, sub-step 3. ...
Page 11 - Check cooling; Switch; Operation
CT87A,B,J ROUND® THERMOSTAT 11 69-0274-6 Check cooling IMPORTANT : To avoid damaging the compressor in the air conditioner, do not operate the cooling system when the outdoor temperature is below 50°F (10°C). 1. If your CT87 has a subbase, set the System switch on the left to Cool. IMPORTANT: After ...
Page 12 - Limited One-Year Warranty
CT87A,B,J ROUND® THERMOSTAT 69-0274-6 G.H. Rev. 08-02 www.honeywell.com/yourhome Automation and Control Solutions Honeywell Honeywell Limited-Honeywell Limitée 1985 Douglas Drive North 35 Dynamic Drive Golden Valley, MN 55422 Scarborough, OntarioM1V 4Z9 Printed in U.S.A. on recycled paper containing...