Installation Instructions
Page 1
... more than one No stage, or an outdoor heating/cooling unit (compressor) with 2-wire cooling-only systems. ® U.S. No No * CT87A is right for your system, visit www.honeywell.com/ yourhome or call Honeywell Customer Care at 1-800-468-1502. CT87A,B,J Round® Thermostat LOW VOLTAGE (15 TO 30 VAC), THERMOSTAT AND MOUNTING HARDWARE 1 Verify that you have...
... more than one No stage, or an outdoor heating/cooling unit (compressor) with 2-wire cooling-only systems. ® U.S. No No * CT87A is right for your system, visit www.honeywell.com/ yourhome or call Honeywell Customer Care at 1-800-468-1502. CT87A,B,J Round® Thermostat LOW VOLTAGE (15 TO 30 VAC), THERMOSTAT AND MOUNTING HARDWARE 1 Verify that you have...
Installation Instructions
Page 2
... SCALE Current setting: If you cannot find the heat LEVER anticipator setting on the old thermostat, you reach Step 8 of MERCURY SWITCH IN A THERMOSTAT system when you can be used to unscrew the cover if it is the current (amp) MERCURY SWITCH rating of your new thermostat; round head screws • Wallplate (CT87A) or subbase (CT87B, CT87J) •...
... SCALE Current setting: If you cannot find the heat LEVER anticipator setting on the old thermostat, you reach Step 8 of MERCURY SWITCH IN A THERMOSTAT system when you can be used to unscrew the cover if it is the current (amp) MERCURY SWITCH rating of your new thermostat; round head screws • Wallplate (CT87A) or subbase (CT87B, CT87J) •...
Installation Instructions
Page 3
... wire using the wiring labels that contains mercury in a sealed tube, do not place your M20133 local waste management authority for instructions regarding recycling and the proper disposal of this control, or of the terminal on the old thermo- stat (Fig. 2). Wrapping wires. CT87A,B,J ROUND® THERMOSTAT 5. Labeling wires. Do not label the...
... wire using the wiring labels that contains mercury in a sealed tube, do not place your M20133 local waste management authority for instructions regarding recycling and the proper disposal of this control, or of the terminal on the old thermo- stat (Fig. 2). Wrapping wires. CT87A,B,J ROUND® THERMOSTAT 5. Labeling wires. Do not label the...
Installation Instructions
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... IN. Position the wallplate or subbase. • If using the cover ring: Position the cover ring against the wall so that the fan and heating/cooling switches are aligned and the two screw holes on the left and right sides of the cover ring is on top. • If attaching... over the cover ring. If installing on an outlet box (subbase shown). 1/2 IN. holes at the locations you work. M20187 69-0274-6 4 ROUND HEAD SCREW (2) A THERMOSTAT WIRING HOLE 1 THE TWO INNER HOLES ARE USED WITH WALLPLATE. 2 IF OUTLET BOX IS HORIZONTAL, MOUNT COVER RING IN POSITION SHOWN, BUT FASTEN WITH...
... IN. Position the wallplate or subbase. • If using the cover ring: Position the cover ring against the wall so that the fan and heating/cooling switches are aligned and the two screw holes on the left and right sides of the cover ring is on top. • If attaching... over the cover ring. If installing on an outlet box (subbase shown). 1/2 IN. holes at the locations you work. M20187 69-0274-6 4 ROUND HEAD SCREW (2) A THERMOSTAT WIRING HOLE 1 THE TWO INNER HOLES ARE USED WITH WALLPLATE. 2 IF OUTLET BOX IS HORIZONTAL, MOUNT COVER RING IN POSITION SHOWN, BUT FASTEN WITH...
Installation Instructions
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CT87A,B,J ROUND® THERMOSTAT 1. Place the cover ring against the outlet box so that the arrow in the middle of the cover ring. 3. Pull the wires through the wiring ... attach the wallplate/subbase to maintain accu- screws, through . 5. Fig. 6. Leveling the wallplate. rate thermostat temperature. 1. To level the subbase, use the leveling posts directly below the Heat and Fan indicators. SPIRIT LEVEL LEVELING POSTS (2) OPENING FOR THERMOSTAT WIRING MOUNTING SLOTS M3319A 2. Tighten the mounting screws after making sure that the wiring holes...
CT87A,B,J ROUND® THERMOSTAT 1. Place the cover ring against the outlet box so that the arrow in the middle of the cover ring. 3. Pull the wires through the wiring ... attach the wallplate/subbase to maintain accu- screws, through . 5. Fig. 6. Leveling the wallplate. rate thermostat temperature. 1. To level the subbase, use the leveling posts directly below the Heat and Fan indicators. SPIRIT LEVEL LEVELING POSTS (2) OPENING FOR THERMOSTAT WIRING MOUNTING SLOTS M3319A 2. Tighten the mounting screws after making sure that the wiring holes...
Installation Instructions
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... both the B and O terminals. 2. Securely tighten the terminal screws. 5. FOR STRAIGHT CONNECTION- Fig. 7. Loosen the terminal screws and slip each old thermostat wire with its matching terminal. 4. CT87A,B,J ROUND® THERMOSTAT 6 Wire the thermostat 1. See Fig. 8 through 13 wiring diagrams. Wiring Cross-reference Wire Label R, RH, 4, V Rc, R W, W1, H Y, Y1, M G, F B O See Fig. 13 Connect to...
... both the B and O terminals. 2. Securely tighten the terminal screws. 5. FOR STRAIGHT CONNECTION- Fig. 7. Loosen the terminal screws and slip each old thermostat wire with its matching terminal. 4. CT87A,B,J ROUND® THERMOSTAT 6 Wire the thermostat 1. See Fig. 8 through 13 wiring diagrams. Wiring Cross-reference Wire Label R, RH, 4, V Rc, R W, W1, H Y, Y1, M G, F B O See Fig. 13 Connect to...
Installation Instructions
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CT87A WALLPLATE R Y W POWER HEAT TO SYSTEM M20183 Fig. 9. CT87B for a 2-wire heating only system. COOL • OFF • HEAT FAN ON RH G RC Y W AUTO • CT87B SUBBASE POWER FAN COOL TO SYSTEM HEAT JUMPER RH TO RC M20185 7 69-0274-6 CT87A for a 4-wire heating/cooling system. R Y W CT87A WALLPLATE WIRE LABELS (LETTERS ON ORIGINAL THERMOSTAT TERMINALS) R 3-WIRE W HOT WATER ZONE VALVE B M20184 Fig. 10. CT87A for a 3-wire hot water heating only system. CT87A,B,J ROUND® THERMOSTAT Fig. 8.
CT87A WALLPLATE R Y W POWER HEAT TO SYSTEM M20183 Fig. 9. CT87B for a 2-wire heating only system. COOL • OFF • HEAT FAN ON RH G RC Y W AUTO • CT87B SUBBASE POWER FAN COOL TO SYSTEM HEAT JUMPER RH TO RC M20185 7 69-0274-6 CT87A for a 4-wire heating/cooling system. R Y W CT87A WALLPLATE WIRE LABELS (LETTERS ON ORIGINAL THERMOSTAT TERMINALS) R 3-WIRE W HOT WATER ZONE VALVE B M20184 Fig. 10. CT87A for a 3-wire hot water heating only system. CT87A,B,J ROUND® THERMOSTAT Fig. 8.
Installation Instructions
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... HEATING POWER FAN TO SYSTEM COOLING POWER TO SYSTEM COOL HEAT Fig. 12. CT87J for a 5-wire heating/cooling system. M20225 COOL • OFF • HEAT FAN ON WG Y P R B O JUMPER W TO Y AUTO • CT87J SUBBASE HEAT FAN TO SYSTEM POWER COOL REVERSING VALVE HEAT REVERSING VALVE DO NOT ATTACH WIRES TO BOTH B AND O M20186 Fig. 13. M20228 69-0274-6 8 CT87A,B,J ROUND® THERMOSTAT...
... HEATING POWER FAN TO SYSTEM COOLING POWER TO SYSTEM COOL HEAT Fig. 12. CT87J for a 5-wire heating/cooling system. M20225 COOL • OFF • HEAT FAN ON WG Y P R B O JUMPER W TO Y AUTO • CT87J SUBBASE HEAT FAN TO SYSTEM POWER COOL REVERSING VALVE HEAT REVERSING VALVE DO NOT ATTACH WIRES TO BOTH B AND O M20186 Fig. 13. M20228 69-0274-6 8 CT87A,B,J ROUND® THERMOSTAT...
Installation Instructions
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... screws complete the installation of the thermostat. Adjusting heat anticipator indicator. HEAT ANTICIPATOR INDICATOR 1.2 .6 .5 .4 .3 .2 HOLE SUITABLE FOR PENCIL POINT TO MOVE INDICATOR .15 SCALE .12 .10 M20226 3. Tightening mounting screws. Fig. 14. IMPORTANT: This prevents the thermostat from being damaged. CT87A,B,J ROUND® THERMOSTAT 7 Mount the thermostat 1. Pull off the thermostat cover and discard the red plastic insert...
... screws complete the installation of the thermostat. Adjusting heat anticipator indicator. HEAT ANTICIPATOR INDICATOR 1.2 .6 .5 .4 .3 .2 HOLE SUITABLE FOR PENCIL POINT TO MOVE INDICATOR .15 SCALE .12 .10 M20226 3. Tightening mounting screws. Fig. 14. IMPORTANT: This prevents the thermostat from being damaged. CT87A,B,J ROUND® THERMOSTAT 7 Mount the thermostat 1. Pull off the thermostat cover and discard the red plastic insert...
Installation Instructions
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..., move the anticipator pointer up by .1 ampere. Snap on the old thermostat, use the setting for your system IMPORTANT: Setting the heat anticipator allows the thermostat to the farthest point left. 2. If you recorded in the table below. CT87A,B,J ROUND® THERMOSTAT 8 Set the heat anticipator for your CT87 has a subbase, set temperature is shown on the...
..., move the anticipator pointer up by .1 ampere. Snap on the old thermostat, use the setting for your system IMPORTANT: Setting the heat anticipator allows the thermostat to the farthest point left. 2. If you recorded in the table below. CT87A,B,J ROUND® THERMOSTAT 8 Set the heat anticipator for your CT87 has a subbase, set temperature is shown on the...
Installation Instructions
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CT87A,B,J ROUND® THERMOSTAT Check cooling IMPORTANT: To avoid damaging the compressor in the air conditioner, do not operate the cooling system when the outdoor temperature is tested, wait five minutes before switching to Cool. IMPORTANT: After heating is below room temperature. Operation To set the System switch on the left to Cool on the top...
CT87A,B,J ROUND® THERMOSTAT Check cooling IMPORTANT: To avoid damaging the compressor in the air conditioner, do not operate the cooling system when the outdoor temperature is tested, wait five minutes before switching to Cool. IMPORTANT: After heating is below room temperature. Operation To set the System switch on the left to Cool on the top...
Installation Instructions
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Honeywell's sole responsibility shall be free from defects in the workmanship or materials, under normal use and service, for a period of one (1) year from state to repair or replace the product ... is defective, (i) return it , postage prepaid, to be to state. If, at any questions concerning this warranty, please write Honeywell Customer Care, Honeywell Inc., 1985 Douglas Dr. N., Golden Valley, MN 55422-3992, or call 1-800-468-1502. CT87A,B,J ROUND® THERMOSTAT Limited One-Year Warranty Honeywell warrants this product, excluding battery, to the following address...
Honeywell's sole responsibility shall be free from defects in the workmanship or materials, under normal use and service, for a period of one (1) year from state to repair or replace the product ... is defective, (i) return it , postage prepaid, to be to state. If, at any questions concerning this warranty, please write Honeywell Customer Care, Honeywell Inc., 1985 Douglas Dr. N., Golden Valley, MN 55422-3992, or call 1-800-468-1502. CT87A,B,J ROUND® THERMOSTAT Limited One-Year Warranty Honeywell warrants this product, excluding battery, to the following address...
