Installation Instructions

Transcription

1 Installation Instructions Twinning Kit for HSI Single-and -Stage Upflow Condensing and Non-Condensing Gas Furnaces KGATW050HSI NOTE: Read the entire instruction manual before starting the installation. This symbol indicates a change since the last issue. TABLE OF CTENTS SAFETY CSIDERATIS... INTRODUCTI... DESCRIPTI AND USAGE... ELECTROSTATIC DISCHARGE (ESD) PRECAUTI... SECTI I: MODELS 58PAV, 58WAV, 8KAV, 95CAV, 480BAV, GBAAV, AND PG8UAA UPFLOW SINGLE-SPEED N- CDENSING HSI FURNACES... Install Furnaces... Connect Electrical Components Heating...4 Connect Electrical Components-Cooling...7 Venting...7 Gas Supply Piping...7 Electrical Supply Connections...8 Start-Up and Adjustment...9 Sequence of Operation...0 SECTI II: MODELS 58TUA, 58UXT, 0AAV, AND 0JAV UPFLOW -STAGE N-CDENSING HSI FURNACES... Install Furnaces... Connect Electrical Components Heating... Connect Electrical Components Cooling...5 Venting...5 Gas Supply Piping...5 Electrical Supply Connections...5 Start-Up and Adjustment...6 Sequence of Operation...7 SECTI III: MODELS 58MCA, 58MXA, 40MAV, 50MAV, 490AAV, AND PG9MAA UPFLOW SINGLE-SPEED CDENSING HSI FURNACES...8 Install Furnaces...8 Connect Electrical Components Heating...8 Connect Electrical Components Cooling...4 Venting...5 Gas Supply Piping...5 Condensate Drain Connections (Furnaces After Serial No. 894A0000)...5 Electrical Supply Connections...5 Start-Up and Adjustment...5 Sequence of Operation...7 SECTI IV: MODELS 58MTA AND 5MAV UPFLOW -STAGE CDENSING HSI FURNACES...7 Install Furnaces...7 Connect Electrical Components Heating...0 Connect Electrical Components Cooling... Venting... Gas Supply Piping... Condensate Drain Connections... Electrical Supply Connections... Start-Up and Adjustment... Sequence of Operation... Form: AG-GATW- Cancels: AG-GATW- Printed in U.S.A. 0-0 Catalog No. 6GA-TW5

2 SAFETY CSIDERATIS Installing and servicing of heating equipment can be hazardous due to gas and electrical components. Only trained personnel should install or service heating equipment. Untrained personnel can perform basic maintenance such as cleaning and replacing filters. All other operations should be performed by trained service personnel. When working on heating equipment, observe precautions in the literature, on tags, and on labels attached to the unit. Follow all safety codes. Wear safety glasses and work gloves. Have a fire extinguisher available. Recognize safety information. This is the safety-alert symbol. When you see this symbol on the furnace and in instructions or manuals, be alert to the potential for personal injury. Understand the signal words DANGER, WARNING, CAUTI, and NOTE. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies a hazard which could result in personal injury or death. CAUTI is used to identify unsafe practices which would result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation. CAUTI: Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. INTRODUCTI IMPORTANT: Only the furnace sizes listed in Tables,, 4, and 5 can be twinned. Both furnaces must have the same product number, including heating and cooling sizes, to achieve correct operation. This furnace twinning kit P/N KGATW050HSI permits connection of upflow, single-speed, non-condensing furnaces (See Fig. and ); upflow, -stage, non-condensing furnaces (See Fig. and ); upflow, single-speed, condensing furnaces (See Fig. 7 and 8) or upflow, -stage, condensing furnaces (See Fig. 8 and 0) to operate as a single unit on the same duct work. The kit is applicable only to upflow furnaces listed in Tables,, 4, and 5. A single non-condensing furnace shall NOT be twinned with a single condensing furnace or with a non-condensing furnace with a different number of speeds. Variable-speed furnaces shall not be twinned. DESCRIPTI AND USAGE This twinning kit is designed for use in upflow, single-speed, non-condensing, hot surface ignition (HSI) furnaces as shown in Table ; upflow, -stage, non-condensing HSI furnaces as shown in Table ; upflow, single-speed, condensing HSI furnaces as shown in Table 4; upflow, -stage, condensing HSI furnaces as shown in Table 5. Refer to the appropriate section for your furnaces. SECTI I: Models 58PAV, 58WAV, 8KAV, 95CAV, 480BAV, GBAAV, and PG8UAA Upflow Single-Speed Non-Condensing HSI Furnaces Single-Stage Heat with Single-Stage Gas-Heat Thermostat Two-Stage Heat with -Stage Gas-Heat Thermostat SECTI II: Models 58TUA, 58UXT, 0AAV, and 0JAV Upflow -Stage Non-Condensing HSI Furnaces Two-Stage Heat with Single-Stage Gas-Heat Thermostat Two-Stage Heat with -Stage Gas-Heat Thermostat SECTI III: Models 58MCA, 58MSA, 58MXA, 40MAV, 45MAV, 50MAV, 490AAV, and PG9MAA Upflow Single-Speed Condensing HSI Furnaces Single-Stage Heat with Single-Stage Gas-Heat Thermostat SECTI IV: Models 58MTA and 5MAV Upflow -Stage Condensing HSI Furnaces Two-Stage Heat with Single-Stage Gas-Heat Thermostat Two-Stage Heat with -Stage Gas-Heat Thermostat The furnaces must be installed to ensure sufficient return air. A combination of full side and bottom inlet plenum or bottom only inlet plenum shall be used for return air to each furnace. The preferred method is to have all return air brought into the bottom of the furnaces through a common bottom plenum. The bottom return-air plenum shall be at least as high as the width of the furnace bottom return-air opening. When there are height limitations, the bottom return-air plenum height can be reduced to 8 in. minimum if entire side return-air opening of each furnace is used in conjunction with the bottom return opening. Rear inlet plenums shall not be used. (See Fig.,, 7, or 0.) WARNING: Do not remove the center return-air partitions between the furnaces. Failure to follow this warning could result in improper auxiliary limit operation, fire, personal injury, or death. Staged heating operation is permitted only with this twinning kit. With the -stage, non-condensing furnaces, low-gas heat in both furnaces is used for first-stage heat, and high-gas heat in both furnaces is used for second-stage heat. With the single-speed, non-condensing, and condensing furnaces, the left-hand furnace is used for first-stage heat, and both furnaces are used for second-stage heat. This kit ensures both furnace blowers operate simultaneously so air flows through the duct work rather than recirculating in a loop between the furnaces. NOTE: As a result of staged heating with single-speed furnaces, the air temperature distribution in the supply plenum may be uneven when only furnace is heating. NOTE: Refer to the Installation, Start-Up, and Operating Instructions supplied with each furnace for information on venting, clearances, start-up, maintenance, and other information not covered in this publication. See Table for kit contents. ELECTROSTATIC DISCHARGE (ESD) PRECAUTI CAUTI: Electrostatic discharge can affect electronic components. Take precautions during furnace installation and servicing to protect the furnace electronic control. Precautions will prevent electrostatic discharges from personnel and hand tools which are held during the procedure. These precautions will help to avoid exposing the control to electrostatic discharge by putting the furnace, the control, and the person at the same electrostatic potential.

3 Table Kit Contents DESCRIPTI PART NO. QUANTITY Foam Strip Relay and Harness Assembly (TKR) Wiring Label Schematic Diagram (Single-Speed Non- Condensing) Wiring Label Connection Diagram (Single-Speed Non- Condensing) Wiring Label Schematic Diagram (-Stage Non-Condensing) 0-40 Wiring Label Connection Diagram (-Stage Non-Condensing) 0-40 Wiring Label Schematic Diagram (Single-Speed Condensing) Wiring Label Connection Diagram (Single-Speed Condensing) Wiring Label-Schematic Diagram (-Stage Condensing) Wiring Label-Connection Diagram (-Stage Condensing) Auxiliary Limit Switch Harness-Main Furnace (ALS-M) Auxiliary Door Switch/Limit Switch Harness Secondary Furnace (ALS-S/ILK-) No. 6 X /4-in. LG Sheet Metal Screw AL76AZ8 7 /4-in. Quick-Connect Wire Terminal HY60AM065 Wire Tie HY76TB5 Snap Bushing HY9NH070 Strain Relief Bushing HW60ZW50 Installation Instructions AG-GATW-. Disconnect all power to the furnace. DO NOT TOUCH THE CTROL OR ANY WIRE CNECTED TO THE CTROL PRIOR TO DISCHARGING YOUR BODY S ELECTROSTATIC CHARGE TO GROUND.. Firmly touch a clean, unpainted, metal surface of the furnace chassis which is close to the control. Tools held in a person s hand during grounding will be satisfactorily discharged.. After touching the chassis you may proceed to service the control or connecting wires as long as you do nothing that recharges your body with static electricity (for example; DO NOT move or shuffle your feet, DO NOT touch ungrounded objects, etc.). 4. If you touch ungrounded objects (recharge your body with static electricity), firmly touch furnace again before touching control or wires. 5. Use this procedure for installed and uninstalled (ungrounded) furnaces. 6. Before removing a new control from its container, discharge your body s electrostatic charge to ground to protect the control from damage. If the control is to be installed in a furnace, follow items through 5 before bringing the control or yourself into contact with the furnace. Put all used AND new controls into containers before touching ungrounded objects. 7. An ESD service kit (available from commercial sources) may also be used to prevent ESD damage. SECTI I: MODELS 58PAV, 58WAV, 8KAV, 95CAV, 480BAV, GBAAV, AND PG8UAA UPFLOW SINGLE-SPEED N-CDENSING HSI FURNACES NOTE: The furnace installed on the left-hand (LH) side will be referred to as the LH furnace, and the furnace installed on the right-hand (RH) side as the RH furnace throughout these instructions. PROCEDURE INSTALL FURNACES Refer to Fig. and for appearance and dimensional drawing of twinned furnaces and their connection locations.. Select identical heating and airflow furnaces. (See Table.). Remove bottom closure panels from both furnaces. (See Fig..) a. Remove screws from bottom front panel. b. Rotate front panel downward to remove. c. Remove bottom closure panel and discard. d. Reinstall bottom front panel.. If return air is to enter side of each furnace, cut open entire return-air opening in appropriate side of each furnace. (See Fig..) 4. Apply factory-supplied foam strips to mating side of each furnace. Locate strips equal distance from top and bottom as shown in Fig Remove gas hole closure from RH furnace only and power hole closure from LH furnace only as indicated in Fig.. 6. Remove 7/8-in. diameter accessory hole closures from mating sides of furnaces. (See Fig. 4.) 7. Position furnaces against each other on return-air plenum. Adjust and shim each furnace to align 7/8-in. diameter holes in both furnaces. 8. Drill two /8-in. holes, approximately in. below discharge flange, from inside top of discharge opening and through both furnaces. (See Fig. 5.) 9. Drive factory-supplied No. 6 X /4-in. LG screw through each hole and tighten until furnaces are secure and foam strips have sealed gap between furnaces.

4 JUNCTI BOX JUNCTI BOX AUXILIARY BLOWER DOOR SWITCH BLOWER DOOR SWITCH BLOWER DOOR SWITCH TKR RELAY 0 TWIN/ TEST CNECTI AUXILIARY LIMIT SWITCHES Fig. Twinning Kit Installed on Non-Condensing Furnaces 0. Insert snap bushing through each adjoining accessory hole of each furnace.. Remove 7/8-in. diameter knockout from blower shelf of LH furnace near front right corner.. Insert strain relief bushing through blower shelf hole.. Connect return- and supply-air ducts to furnaces. Seal duct connections to prevent air leakage. 4. Move 5-v junction box JB in LH furnace from right-hand side to left-hand side. For models produced before January 995, blower door switch ILK in LH furnace must also be moved from right-hand side to left-hand side. WARNING: DO NOT use the back of the furnace for return-air duct connections as limit cycling will occur. A failure to follow this warning can cause a fire, personal injury, or death. A957 PROCEDURE CNECT ELECTRICAL PENTS HEATING WARNING: Make no connections between the R 4-vac connector in furnace and the R 4-vac connector in other furnace. Failure to follow this warning can cause a fire, personal injury, or death. See electrostatic discharge precaution on page.. Remove control doors and blower access doors from both furnaces.. Install twinning kit relay (TKR) and harness assembly. The twinning kit can be used for single-stage or -stage heating operation. Single-Stage Heat with Single-Stage Gas-Heat Thermostat (Field Supplied) NOTE: This application allows both furnaces to operate as furnace in gas heat mode as determined by single-stage thermostat operation. Both furnaces operate in heating mode simultaneously. See furnace Installation, Start-Up, and Operating Instructions for further details on this heating mode. a. Secure relay of TKR assembly to LH furnace control mounting bracket using factory-supplied No. 6 X /4-in. LG screws. See Fig. 6 for location of holes to be drilled. NOTE: See Fig. 7. b. Connect TKR white wire labeled W from TKR to LH furnace control thermostat connection W. c. Connect TKR black wire labeled C from TKR to LH furnace control thermostat connection 4V. 4

5 AIRFLOW MAIN OR LH FURNACE F D A FLUE COLLARS D 6 6 AIRFLOW SECDARY OR RH FURNACE 9 OUTLET IN. DIA HOLE POWER ENTRY 7 8-IN. DIA HOLE CLOSURE ACCESSORY 4-IN. DIA HOLE GAS ENTRY -IN.DIA HOLE THERMOSTAT WIRE ENTRY IN. DIA HOLE CLOSURE, POWER ENTRY -IN. DIA HOLE CLOSURE R.H. GAS ENTRY 7 8-IN. DIA HOLE CLOSURE, ACCESSORY -IN. DIA HOLE CLOSURE, THERMOSTAT WIRE ENTRY 4 4 SIDE INLET E E 6 BOTTOM INLET INLET INLET Fig. Dimensional Drawing for Twinned Single-Speed Non-Condensing Furnaces A07 Table 58PAV, 58WAV, 8KAV, 95CAV, 480BAV, GBAAV, and PG8UAA Single-Speed Non-Condensing Furnace Dimensions (In.) INPUT HEATING SIZE (BTUH) NOMINAL COOLING SIZE (BTUH) A D E F 88,000 48, /6 9-/8 9-/ 40-/6 0,000 48, /6 9-/8 9-/ 40-/6 0,000 60, /6-7/8 47-/6,000 48, /6 9-/8 9-/ 40-/6,000 60, /6-7/8 47-/6 54,000 60, /6-7/8 47-/6 This kit applies to the above furnaces with the date codes of 594 and later. FRT FILLER PANEL BOTTOM CLOSURE PANEL Fig. Removing Bottom Closure Panel d. Connect TKR yellow wire labeled TEST/TWIN (loose wire end near TKR relay) to LH furnace control TEST/TWIN terminal. e. Route remaining 4 loose TKR wires through: (.) Strain relief bushing previously installed in 7/8-in. hole in right-hand side of blower shelf. (.) Gas control compartment of LH furnace. (.) Snap bushings previously installed between furnaces. (See Fig. 4.) 5 A9047

6 6 REMOVE 7 8-IN. DIA ACCESSORY HOLE CLOSURE FOAM STRIPS RH FURNACE Fig. 5 Attaching Furnaces Together A966 Fig. 4 Location of Foam Strips A95 f. Connect TKR red wire labeled R-Secondary from TKR to RH furnace control thermostat connection R. g. Connect TKR white wire labeled W-Secondary from TKR to RH furnace control thermostat connection W. h. Connect TKR black wire labeled C-Secondary from TKR to RH furnace control thermostat connection 4V. i. Connect TKR yellow wire labeled TEST SECDARY from LH furnace control TEST terminal to RH furnace control TEST terminal. j. Proceed to item Install LH furnace auxiliary limit switch harness ALS-M to complete electrical connections. Two-Stage Heat with -Stage Gas-Heat Thermostat (Field Supplied) NOTE: ALL thermostat connections are to be made to LH furnace control LY. (See Fig. 7.) NOTE: This application allows only the LH furnace to operate for first-stage heat mode or both furnaces to operate for second-stage heat mode as determined by a -stage thermostat. See furnace Installation, Start-Up, and Operating Instructions for further details on this heating mode. To operate furnaces in -stage heating mode when a -stage thermostat controls the staging, install TKR as described above then modify TKR wiring as follows: a. Disconnect TKR white wire labeled W from the LH furnace control thermostat connection W. b. Cut off terminal of TKR white wire labeled W and strip /4 in. c. Connect -stage thermostat W connection to TKR white wire labeled W. CAUTI: Supply-air temperature will be uneven left-to-right when only main system is operating. NOTE: ALL other -stage thermostat connections are to be made to LH furnace control LY. (See Fig. 8.). Install LH furnace auxiliary limit switch harness ALS-M. NOTE: LH furnace ALS-M assembly DOES NOT include door switch. a. Drill /8-in. hole in blower housing 0 in. below blower shelf. (See Fig..) b. Position ALS-M so reset button faces front of furnace. c. Secure bracket to blower housing using factory-supplied No. 6 X /4-in. LG screw. d. Disconnect red transformer wire from LH furnace control SEC- connection. e. Cut off the /6-in. quick-connect terminal from red transformer wire. f. Strip the red wire /8 in. and secure the factory-supplied /4-in. quick-connect terminal. g. Connect red transformer wire connector to ALS-M wire connector PL7 labeled TRANS ASSY. h. Connect ALS-M wire connector labeled DOOR SWITCH or SEC to LH furnace control SEC- terminal. i. Route -wire ALS-M connector PL6 through: (.) Strain relief bushing previously installed in 7/8-in. hole in right-hand side of blower shelf. (.) Gas control compartment of LH furnace. (.) Snap bushings previously installed between furnaces into gas control compartment of RH furnace. 4. Install RH furnace auxiliary door switch and auxiliary limit switch harness ALS-S/ILK-. NOTE: RH furnace auxiliary limit switch harness assembly ALS-S/ILK- has door switch included. a. Drill /8-in. hole in blower housing 0 in. below blower shelf. (See Fig..) b. Position ALS-S with terminals facing front of furnace. c. Secure bracket to blower housing using factory-supplied No. 6 X /4-in. LG screw. 6

7 R G L L 4 TKR RELAY CTROL MOUNTING BRACKET 4 W 4 V 4 W/W Y/Y HUM TWIN TEST LED SEC- SEC- PR -COOL -GAS -HEAT LO-GAS -HEAT FU M S PR EAC- EAC- PARK CTROL Fig. 6 Twinning Kit Relay Mounted on Control Mounting Bracket for LH Furnace (Two-Stage Control Shown) d. Relocate RH furnace junction box JB from left side to right side as shown in Fig. if JB is not at right-hand side of RH furnace. For models produced before January 995, blower door switch ILK must also be moved when JB changes location. e. Position auxiliary door switch ILK- on left-hand side of RH furnace. f. Secure auxiliary door switch ILK- using factory-supplied No. 6 X /4-in. LG screw. g. Route -wire harness connector PL6 of ALS-S/ILK- assembly up through snap bushing in 7/8-in. hole in left side of blower shelf and into gas control compartment. h. Connect RH ALS-S connector PL6 to LH ALS-M connector PL6 that was routed through furnace casings. 5. Select identical blower motor speed taps at control center motor connectors in both furnaces. A07 CAUTI: Failure to select identical blower speed taps in both furnaces can result in overheating of furnace components and possible loss of furnace operation and damage to the furnaces. 6. Dress wires to ensure they do not contact sharp or moving parts nor interfere with blower operation, removal of filters, or operation of switches. 7. Make all thermostat connections to LH furnace only. PROCEDURE CNECT ELECTRICAL PENTS-COOLING WARNING: Make no connections between the R 4-vac connector in furnace and the R 4-vac connector in other furnace. Failure to follow this warning can cause a fire, personal injury, or death. When installing twinned outdoor units with twinned gas furnaces, it is necessary to use a field-supplied 4-vac pilot-duty relay and a field-supplied 4/5-vac transformer as shown in Fig. 7 or 8 to prevent overloading furnace 4/5-vac transformer. PROCEDURE 4 VENTING Refer to Installation, Start-Up, and Operating Instructions supplied with each furnace for venting information. CAUTI: When common-venting twinned, Category I (negative-pressure venting), non-condensing furnaces, excessive condensate may occur as a result of oversized vent systems. Dedicated vents and/or proper vent sizing per the furnace Installation, Start-Up, and Operating Instructions will reduce the potential for condensation. PROCEDURE 5 GAS SUPPLY PIPING NOTE: All gas connections must be made through exposed outer side of each furnace. Do not common connect any connection other than supplyand return-air ducts. 7

8 SINGLE-STAGE INDOOR THERMOSTAT W R NOTES:. TRANSFORMER = 5 VAC PRIMARY/4 VAC SECDARY/40 VA.. RELAYS = 4 VAC COILS/PILOT DUTY/NORMALLY OPEN. G C Y LEFT HAND FURNACE (MAIN) RIGHT HAND FURNACE (SECDARY) COIL Y C G R W TWIN Y C G R W RELAY TEST (FIELD SUPPLIED) NOTE TWIN TEST TKR 4 4 VAC TRANS (FIELD SUPPLIED) 5 VAC NOTE C Y C Y OUTDOOR UNIT NO. OUTDOOR UNIT NO. Fig. 7 Twinning Single-Speed Outdoor Units with Single-Speed Furnaces with a Single-Stage Thermostat Furnaces are recommended to be provided with a single shutoff valve. However, individual shutoff valves may be required by local codes or jurisdictions. Refer to Installation, Start-Up, and Operating Instructions provided with each furnace for additional gas supply information. PROCEDURE 6 ELECTRICAL SUPPLY CNECTIS NOTE: All electrical power connections must be made through exposed outer side of each furnace. Do not common connect any connection other than supply- and return-air ducts.. Each furnace shall be connected to its own 5-vac power supply. The twinning kit installation interconnects the furnaces, allowing them to operate as a single furnace. The L (black) connection to each furnace must be connected to circuit breakers connected to the same service panel 5-vac phase leg. On single-phase (residential) systems, each furnace circuit breaker should be located directly across from each other in service panel, or each furnace circuit breaker should be located on the same side of service panel, but must skip space to be connected to the same leg of the -phase power supply. On -phase (commercial) systems, each furnace circuit breaker should be located directly across from each other in service panel, or each furnace circuit breaker should be located on the same side of service panel, but must skip spaces to be connected to the same leg of the -phase power supply. The proper 5-vac phasing of furnace connections permits 4-vac transformer phasing as described below.. Phasing of the connected 4-vac transformer secondary circuits can be determined with the LED status of both furnaces. See furnace Installation, Start-Up, and Operating Instructions and status code labels on blower doors. The furnaces transformers black leads should be connected to PR connectors and white leads to PR connectors on controls. If or both LEDs are rapidly flashing, disconnect lead at TEST/TWIN terminal of LH furnace and observe LED at each furnace. IF: a. Both LEDs are on continuously: System phasing is okay. b. One or both LEDs are rapidly flashing: 8 A07

9 TWO-STAGE INDOOR THERMOSTAT W W/W R G C Y Y/Y NOTE NOTES:. FOR TWO-STAGE COOLING, USE RELAY AND (FIELD SUPPLIED) AS SHOWN.. TRANSFORMER = 5 VAC PRIMARY/4 VAC SECDARY/40 VA.. RELAYS = 4 VAC COILS/PILOT DUTY/NORMALLY OPEN. 4. FOR A DUAL-CIRCUITED SINGLE EVAPORATOR COIL THAT COVERS BOTH FURNACE AIR OUTLETS, INTERCHANGE THE THERMOSTAT CNECTIS AT Y AND Y/Y FOR STAGED BLOWER OPERATI. LEFT HAND FURNACE (MAIN ) RIGHT HAND FURNACE (SECDARY) COIL COIL Y C G R W TWIN Y C G R W TEST RELAY RELAY NOTE (FIELD SUPPLIED) NOTE TKR 4 TWIN TEST 4 VAC TRANS (FIELD SUPPLIED) 5 VAC NOTE C Y C Y OUTDOOR UNIT NO. OUTDOOR UNIT NO. Fig. 8 Twinning Single-Speed Outdoor Units with Single-Speed Furnaces with a -Stage Thermostat (.) Line voltage polarity is reversed (.) Reverse SEC- and SEC- in furnace with rapid flashing LED. c. One LED is off, LED is on continuously: (.) The 4-vac circuit is inoperative on furnace with LED light off. (.) Check transformers, auxiliary limits, and door switches in both furnaces and correct problem.. Reconnect lead at TWIN/TEST terminal of LH furnace and observe LED at each furnace. The LEDs will glow steady for proper phasing. PROCEDURE 7 START-UP AND ADJUSTMENT Refer to Installation, Start-Up, and Operating Instructions supplied with furnaces for detailed information.. Shut off all power and gas to both furnaces.. Position blower off delay switches on controls in BOTH furnaces to SAME desired gas heat blower off delay. (See Fig. 9.) See furnace Installation, Start-Up, and Operating Instructions for further details. If furnace control has blower off delay switches and the other has a fixed jumper wire which sets blower off delay at 5 sec, the control with selectable switches MUST be set for 5 sec off delay.. Attach twinning connection diagram label over existing wiring label on inside of LH furnace blower door. 4. Attach twinning schematic diagram label over existing wiring label on inside of RH furnace blower door. 5. Turn on power and gas to both furnaces. 6. Reinstall blower access doors on both furnaces. 9 A074

10 BLOWER DELAY SWITCH OR JUMPER WIRE TEST/TWIN G R Y W Com 4V HUM 4-VAC THERMOSTAT LEAD TERMINALS LED OPERATI & DIAGNOSTIC LIGHT SEC- -AMP FUSE COOL HEAT 4-VAC TRANSFORMER SEC- SPARE BLOWER SPEED SELECTI TERMINALS SPARE 5-VAC (L) POWER SUPPLY 5-VAC (L) NEUTRAL CNECTI Fig. 9 Single-Stage Furnace Control 7. Operate furnaces through cycles in each mode to confirm correct operation by operating only thermostat. a. Single-stage gas heating thermostat R-to-W for gas heat. First stage of a -stage thermostat causes LH furnace to operate in gas-heat mode. b. First and second stage of -stage heating thermostat R-to-W/W-and-W causes both furnaces to operate in gas-heat mode. c. Thermostat R-to-G for continuous fan or low-cooling blower. d. Cooling thermostat R-to-G-and-Y for single-speed cooling blower. 8. Reinstall control doors on both furnaces. 9. Instruct user in operation of furnace and thermostat. PROCEDURE 8 SEQUENCE OF OPERATI See Fig. 0 and for single-speed non-condensing furnace twinning connection and schematic wiring diagrams while reviewing the sequence of operation. Twinning operation is controlled by LH furnace. The TWIN/TEST and 4 connection wires ensure the furnaces coordinate their blower operation. When either furnace requires blower operation, both furnaces operate their blowers at the same speed. Both furnaces operate simultaneously in the same mode: heat, cool, or continuous fan. Exceptions can occur if a safety switch on either furnace is activated (such as pressure switch, flame roll-out switch, main limit switch, draft safeguard switch, twinning kit auxiliary limit switch, or flame-proving sensor). In such a case, the other furnace continues to operate unless open switch is the flame roll-out, main limit, or twinning kit auxiliary limit switch, in which case both furnaces respond. Before performing component test, disconnect TKR yellow wire labeled TEST from LH furnace control TEST/TWIN terminal. After removing yellow wire, component test can be initiated on each furnace individually as stated in Installation, Start-Up, and Operating Instructions. Single-Stage Heat with Single-Stage Gas-Heat Thermostat See Section I, Procedure for furnace and kit components used.. Single-stage thermostat causes both furnaces to operate in heating mode.. Operation in ALL modes is the same for twinned furnaces as for an individual furnace. See furnace Installation, Start-Up, and Operating Instructions for more information on sequence of operation. Two-Stage Heat with -Stage Gas-Heat Thermostat See Section I, Procedure for furnace and kit components used.. The -stage thermostat causes the furnaces to operate in first-stage heat (LH furnace operates in heat while RH furnace blower operates but RH furnace is not heating) or causes the furnaces to operate in second-stage heat (both furnaces operate in heat), depending on whether or thermostat stages are calling for heat. 0 A958

11 PCB NOTE # (NOT ALL MODELS) BLOWER DELAY SELECTI CHART 90 SEC 5 SEC 80 SEC 5 SEC GVR BLOWER SW G R DELAY Y SW W 4V HUM TEST/TWIN /LO RELAY PL SEC- FU LED SEC- HSIR IDR BLWR BLOWER COOL SPARE- SPEED SELECT HEAT SPARE- L EAC- PL 0 L MAIN OR LH FURNACE VAC PR PL PL5 HSI PR 4 VAC-A FUSE EAC-.0 AMP IDM GRN/ NOTES #9 AND #4 NOTES #0 AND #4 NOTE #5 PRS NOTE #8 DSS 4 BLOWER SW G NO C DSS PRS R NOTE #5 LGPS NOTE PCB TKR DELAY Y #5 NOTE # SW W LGPS (NOT ALL MODELS) C OM 4V BLOWER DELAY HUM SELECTI CHART TEST/TWIN NOTE #5 LED FRS 90 SEC -M GV LS FL -M GV 5 SEC FRS LS FL FRS 80 SEC PL -C FSE -C GRN/ GRN/ 5 SEC FSE NOTE #5 GRN/ NOTE # FRS NOTE #8 PL6 GVR GRN/ ILK- ALS-S SEC- SEC- SECDARY NOTE #8 /LO OR RH () RELAY ALS-M PL7 FURNACE () 4 VAC-A NOTE # FU FUSE NOTE # () GRN/ GRN/ OL (MED-) HSIR IDR BLWR BLOWER COOL SPARE- () OL SPEED (MED-) NOTE #7 START SELECT START TRAN HEAT SPARE- NOTE #7 L EAC- (MED-LO) PL (MED-LO) PL PR (LO) BLWM 0 VAC BLWM EAC- (LO) L PR () () ILK JB CAP FUSED DISCNECT SWITCH (WHEN REQ D) NOTE #4 LEGEND ALS-M MAIN AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N.C.) PCB PRINTED CIRCUIT BOARD ALS-S SECDARY AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N.C.) PL 9-CIRCUIT CNECTOR BLWR BLOWER MOTOR RELAY, SPST-(N.O.) PL -CIRCUIT CNECTOR PL -CIRCUIT IDM CNECTOR PL5 -CIRCUIT HSI CNECTOR PL6 -CIRCUIT TWINNING KIT CNECTOR PL7 -CIRCUIT TWINNING KIT IN-LINE SPLICE PRS PRESSURE SWITCH, SPST-(N.O.) TEST / TWIN PENT TEST & TWIN TERMINAL TKR TWINNING KIT RELAY, SPST-(N.O.) GV GAS VALVE-UNDANT OPERATORS TRAN TRANSFORMER-5VAC / 4VAC GVR GAS VALVE RELAY, DPST-(N.O.) /LO BLOWER MOTOR SPEED CHANGE RELAY, SPDT HSI HOT SURFACE IGNITER (5 VAC) HSIR HOT SURFACE IGNITER RELAY, SPST-(N.O.) HUM 4VAC HUMIDIFIER CNECTI (0.5 AMP. MAX.) IDM INDUCED DRAFT MOTOR, SHADED-POLE IDR INDUCER MOTOR RELAY, SPST-(N.O.) ILK BLOWER DOOR INTERLOCK SWITCH, SPST-(N.O.) ILK- SECDARY AUX. BLOWER DOOR INTERLOCK SWITCH, SPST-(N.O.) JB JUNCTI BOX REV. D BLWM CAP EAC- EAC- FRS FSE LED LGPS BLOWER MOTOR, - OR 4-SPEED, PERMANENT-SPLIT-CAPACITOR CAPACITOR ELECTRIC AIR CLEANER CNECTI (5 VAC.0 ELECTRIC AIR CLEANER CNECTI (M) FLAME ROLLOUT SW. -MANUAL RESET, SPST-(N.C.) FLAME-PROVING SENSOR ELECTRODE LIGHT-EMITTING DIODE FOR STATUS CODES LOW GAS-PRESSURE SWITCH, SPST (N.O.) DSS FL FU LS DRAFT SAFEGUARD SWITCH, AUTO-RESET, SPST-(N.C.) FUSIBLE LINK FUSE, AMP, AUTOMOTIVE BLADE TYPE, FACTORY INSTALLED LIMIT SWITCH, AUTO RESET, SPST(N.C.) FU OL AMP MAX.) FUSE OR CIRCUIT-BREAKER CURRENT-INTERRUPT DEVICE AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SWITCH, SPST-(N.C.) (FIELD INSTALLED & SUPPLIED) GND FU HSI PL5 IDM.0 AMP GRN/ JUNCTI NOTES:. If any of the original equipment wire is replaced, use wire rated UNMARKED TERMINAL for 05 C of the same type.. Inducer (IDM) and blower (BLWM) motors contain internal PCB CTROL TERMINAL auto-reset thermal overload switches (OL).. Blower motor speed selections are for average conditions, see FACTORY WIRING (5VAC) installation instructions for details on optimum speed selection. 4. Use only copper wire between the disconnect switch and the FACTORY WIRING (4VAC) furnace. FIELD WIRING (5VAC) 5. This wire must be connected to furnace sheetmetal for control to prove flame. FIELD ACCESSORY WIRING (4VAC) Replace only with a AMP fuse. Yellow lead (MED-) is not on all motors. FIELD WIRING TERMINAL, NOTE #4 8. Passes through holes in casings. ALS-S & ILK- are located in the secondary furnace blower compartment. FIELD GROUND Make thermostat connections to only the LH furnace. Make no thermostat connections to RH furnace. EQUIPMENT GROUND. Blower-on delay, gas heating 40 seconds, cooling or heat pump seconds. FIELD SPLICE. Blower-off delay, gas heating 90, 5, 80 or 5 seconds (5 seconds only on some models), cooling or heat pump PLUG RECEPTACLE 90 seconds.. Ignition-lockout will occur after four consecutive unsuccessful WIRES PASSING THROUGH HOLES IN trials-for-ignition. Control will auto-reset after three hours. CASINGS FROM LH TO RH FURNACE. 4. Some models may have spade quick connect terminals. 5. Factory Connected when LGPS not used. ILK JB TRAN CAP FUSED DISCNECT SWITCH (WHEN REQ D) NOTE #4 GND FU Fig. 0 Connection Diagram for Twinned Single-Speed Non-Condensing Furnaces A087

12 TKR TO 5VAC FIELD DISCNECT NOTE #4 L L ILK MAKE THERMOSTAT CNECTIS TO LY THE LH FURNACE ALS-M 4 PL7 L BLWR HSIR IDR TEST/TWIN FU NOTE #6 HUM R W Y G 4V NOTE # EQUIPMENT GROUND /LO EAC- EAC- SPARE- HEAT SPARE- COOL HSI PL PL5 PR 5VAC PR TRAN PL 4VAC SEC- GVR- HSIR BLWR IDR CPU MAIN OR LH FURNACE SEC- /LO GVR GVR- LEGEND ALS-M MAIN AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N.C.) ALS-S SECDARY AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N.C.) BLWR BLOWER MOTOR RELAY, SPST-(N.O.) BLWM BLOWER MOTOR, - OR 4-SPEED, PERMANENT-SPLIT-CAPACITOR CAP CAPACITOR CPU MICROPROCESSOR AND CIRCUITRY DSS DRAFT SAFEGUARD SWITCH, AUTO-RESET, SPST-(N.C.) EAC- ELECTRIC AIR CLEANER CNECTI (5 VAC.0 AMP MAX.) EAC- ELECTRIC AIR CLEANER CNECTI (M) FL FUSIBLE LINK FRS FLAME ROLLOUT SW. -MANUAL RESET, SPST-(N.C.) FSE FLAME-PROVING SENSOR ELECTRODE FU FUSE, AMP, AUTOMOTIVE BLADE TYPE, FACTORY INSTALLED GV GAS VALVE-UNDANT OPERATORS GVR GAS VALVE RELAY, DPST-(N.O.) - = VALVE - = HUMIDIFIER /LO BLOWER MOTOR SPEED CHANGE RELAY, SPDT HSI HOT SURFACE IGNITER (5 VAC) LO MED LO MED NOTE #7 NOT USED FRS LS OL PL DSS NOT USED NOTE # NOT USED 9 START NOTE # -M BLWM SCHEMATIC DIAGRAM (NATURAL GAS & PROPANE) FRS PRS NOTE # GV CAP IDM LGPS FSE L L MAKE NO THERMOSTAT CNECTIS TO RH FURNACE PASSES THROUGH HOLES IN CASINGS TEST/TWIN NOTE # HUM R W HSIR HOT SURFACE IGNITER RELAY, SPST-(N.O.) HUM 4VAC HUMIDIFIER CNECTI (0.5 AMP. MAX.) IDM INDUCED DRAFT MOTOR, SHADED-POLE IDR INDUCER MOTOR RELAY, SPST-(N.O.) ILK BLOWER DOOR INTERLOCK SWITCH, SPST-(N.O.) ILK- SECDARY AUX. BLOWER DOOR INTERLOCK SWITCH, SPST-(N.O.) LED LIGHT-EMITTING DIODE FOR STATUS CODES LGPS LOW GAS-PRESSURE SWITCH, SPST (N.O.) LS LIMIT SWITCH, AUTO RESET, SPST(N.C.) OL AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SW., SPST (N.C.) PCB PRINTED CIRCUIT BOARD PL 9-CIRCUIT CNECTOR PL -CIRCUIT CNECTOR PL -CIRCUIT IDM CNECTOR PL5 -CIRCUIT HSI CNECTOR PL6 -CIRCUIT TWINNING KIT CNECTOR FL -C NOTE #5 ILK Y G TO 5VAC FIELD DISCNECT NOTE #4 L L EQUIPMENT GROUND BLWR HSIR IDR FU EAC- /LO EAC- SPARE- HEAT SPARE- COOL HSI PL PL5 PR 5VAC PR TRAN PL 4VAC NOT USED NOTE #6 SEC- GVR- HSIR BLWR IDR CPU SEC- /LO GVR 4V PL6 ALS-S NOTE #8 PL7 PRS TEST / TWIN TKR TRAN NOTE #7 GVR- LO MED LO MED 4 8 FRS 7 LS PL OL 5 6 NOT USED NOT USED 9 ILK- SECDARY OR RH FURNACE NOTE # NOTE # DSS -M BLWM START -CIRCUIT TWINNING KIT IN-LINE SPLICE PRESSURE SWITCH, SPST-(N.O.) PENT TEST PIN AND TWIN CNECTOR TWINNING KIT RELAY, SPST-(N.O.) TRANSFORMER-5VAC / 4VAC JUNCTI UNMARKED TERMINAL PCB CTROL TERMINAL FACTORY WIRING (5VAC) FACTORY WIRING (4VAC) PRS IDM LGPS CAP FRS FSE FL NOTE # GV -C NOTE #5 L NOTES:. If any of the original equipment wire is replaced use wire rated for 05 C of the same type.. Inducer (IDM) and blower (BLWM) motors contain internal auto-reset thermal overload switches (OL).. Blower motor speed selections are for average conditions, see installation instructions for details on optimum speed selection. 4. Use only copper wire between the disconnect switch and the furnace. 5. This wire must be connected to furnace sheetmetal for control to prove flame. 6. Replace only with a AMP fuse. 7. Yellow lead (MED-) is not on all motors. 8. ALS-S & ILK- are located in the secondary furnace blower compartment. 9. Blower-on delay, gas heating 40 seconds, cooling or heat pump seconds. 0. Blower-off delay, gas heating 90, 5, 80 or 5 seconds (5 seconds only on some models), cooling or heat pump 90 seconds.. Ignition-lockout will occur after four consecutive unsuccessful trials-forignition. Control will auto-reset after three hours.. Some models may have spade quick-connect terminals.. Factory connected when LGPS not used. FIELD ACCESSORY WIRING (4VAC) CDUCTOR PCB FIELD WIRING TERMINAL, NOTE # FIELD GROUND EQUIPMENT GROUND FIELD SPLICE PLUG RECEPTACLE REV. D Fig. Schematic Diagram for Twinned Single-Speed Non-Condensing Furnaces A088

13 AIRFLOW MAIN OR LH FURNACE F D A FLUE COLLARS D 6 6 AIRFLOW SECDARY OR RH FURNACE 9 OUTLET IN. DIA HOLE POWER ENTRY 7 8-IN. DIA HOLE CLOSURE ACCESSORY 4-IN. DIA HOLE GAS ENTRY -IN.DIA HOLE THERMOSTAT WIRE ENTRY IN. DIA HOLE CLOSURE, POWER ENTRY -IN. DIA HOLE CLOSURE R.H. GAS ENTRY 7 8-IN. DIA HOLE CLOSURE, ACCESSORY -IN. DIA HOLE CLOSURE, THERMOSTAT WIRE ENTRY 4 4 SIDE INLET BOTTOM INLET 6 E E 6 INLET A07 Fig. Dimensional Drawing for Twinned -Stage Non-Condensing Furnaces. Operation in ALL modes is the same for twinned furnaces as for an individual furnace. See furnace Installation, Start-Up, and Operating Instructions for more information on sequence of operation. SECTI II: MODELS 58TUA, 58UXT, 0AAV, AND 0JAV UPFLOW -STAGE N-CDENSING HSI FURNACES PROCEDURE INSTALL FURNACES NOTE: Multipoise units must be installed in UPFLOW configuration. Refer to Fig. and for appearance and dimensional drawing of twinned furnaces and their connection locations.. Select identical heating and airflow furnaces. (See Table.). Remove bottom closure panels from both furnaces. (See Fig..) a. Remove screws from bottom front panel. b. Rotate front panel downward to remove. c. Remove bottom closure panel and discard. d. Reinstall bottom front panel.. If return air is to enter side of each furnace, cut open entire return-air opening in appropriate side of each furnace. (See Fig..) 4. Apply factory-supplied foam strips to mating side of each furnace. Locate strips equal distance from top and bottom as shown in Fig Remove gas and power hole closures from RH furnace only as indicated in Fig.. 6. Remove 7/8-in. diameter accessory hole closures from mating sides of furnaces. (See Fig. 4.) 7. Position furnaces against each other on return-air plenum. Adjust and shim each furnace to align 7/8-in. diameter holes in both furnaces. 8. Drill two /8-in. holes, approximately in. below discharge flange, from inside top of discharge opening and through both furnaces. (See Fig. 5.) 9. Drive factory-supplied No. 6 X /4-in. LG screw through each hole and tighten until furnaces are secure and foam strips have sealed gap between furnaces. 0. Insert snap bushing through each adjoining accessory hole of each furnace.. Remove 7/8-in. diameter knockout from blower shelf of LH furnace near front right corner.. Insert strain relief bushing through blower shelf hole.. Connect return- and supply-air ducts to furnaces. Seal duct connections to prevent air leakage. 4. Move 5-v junction box JB in LH furnace from right-hand side to left-hand side. For models produced before January 995, blower door switch ILK in LH furnace must also be moved from right-hand side to left-hand side. WARNING: DO NOT use the back of the furnace for return-air duct connections as limit cycling will occur. A failure to follow this warning can cause a fire, personal injury, or death. INLET PROCEDURE CNECT ELECTRICAL PENTS HEATING WARNING: Make no connections between the R 4-vac connector in furnace and the R 4-vac connector in other furnace. Failure to follow this warning can cause a fire, personal injury, or death. See electrostatic discharge precaution on page.. Remove control and blower access doors from both furnaces.

14 INPUT HEATING SIZE (BTUH) Table 58TUA, 0AAV, and 0JAV -Stage Non-Condensing Furnace Dimensions (In.) NOMINAL COOLING SIZE (BTUH) A D E F 80,000 48, /6 9-/8 9-/ 40-/6 00,000 48, /6 9-/8 9-/ 40-/6 00,000 60, /6-7/8 47-/6 0,000 48, /6 9-/8 9-/ 40-/6 0,000 60, /6-7/8 47-/6 0,000 60, /6-7/8 47-/6. Determine desired furnace control operation and see appropriate section for use and application of twinning kit relay and harness assembly (TKR). Two-Stage Heat with Single-Stage Gas-Heat Thermostat (Field-Supplied) NOTE: This application allows both furnaces to operate in either high- or low-gas-heat as determined by adaptive mode of both furnace controls. See furnace Installation, Start-Up, and Operating Instructions for further details on this heating mode. a. Remove black and yellow wires from wire-tied TKR harness assembly for later use. b. Discard relay, red wire, and both white wires from TKR harness assembly. c. Use field-supplied electrical tape to insulate black wire s /4-in. quick-connect terminal labeled. d. Connect black wire terminal labeled C to LH furnace control thermostat connection 4. e. Connect yellow wire terminal labeled TEST to LH furnace control TWIN/TEST terminal. f. Route black and yellow wire loose ends through snap bushings previously installed between furnaces. (See Fig. 4.) g. Connect black wire terminal labeled C-SECDARY to RH furnace control thermostat connection 4. h. Connect yellow wire terminal labeled TEST SECDARY to RH furnace control TWIN/TEST terminal. i. Connect yellow wire terminal labeled TEST SECDARY to RH furnace control TWIN/TEST terminal. j. Proceed to item to complete electrical connections. Two-Stage Heat with -Stage Gas-Heat Thermostat (Field Supplied) NOTE: This attachment allows both furnaces to operate in either high- or low-gas heat as determined by thermostat s -stage operation. See furnace Installation, Start-Up, and Operating Instructions for further details on this heating mode. a. Secure relay of TKR assembly to LH furnace control mounting bracket using factory-supplied No. 6 X /4-in. LG screws. See Fig. 6 for location of holes to be drilled. b. Connect TKR white wire labeled W from TKR to LH furnace control thermostat connection W/W. c. Connect TKR black wire labeled C from TKR to LH furnace control thermostat connection 4. d. Connect TKR yellow wire labeled TEST (loose wire end near TKR) to LH furnace control TWIN/TEST terminal. e. Route remaining 4 loose TKR wires through: (.) Strain relief bushing previously installed in 7/8-in. hole in right side of blower shelf. (.) Gas control compartment of LH furnace. (.) Snap bushings previously installed between furnaces. (See Fig. 4.) f. Connect TKR red wire labeled R-SECDARY from TKR to RH furnace control thermostat connection R. g. Connect TKR white wire labeled W-SECDARY from TKR to RH furnace control thermostat connection W/W. h. Connect TKR black wire labeled C-SECDARY from TKR to RH furnace control thermostat connection 4V. i. Connect TKR yellow wire labeled TEST SECDARY from LH furnace control TWIN/TEST terminal to RH furnace control TWIN/TEST terminal. j. Proceed to item to complete electrical connections.. Install LH furnace auxiliary limit switch harness ALS-M. NOTE: LH furnace ALS-M assembly DOES NOT include door switch. a. Drill /8-in. hole in blower housing 0 in. below blower shelf. (See Fig..) b. Position ALS-M so reset button faces front of furnace. c. Secure bracket to blower housing using factory-supplied No. 6 X /4-in. LG screw. d. Disconnect red transformer wire from LH furnace control SEC- connection. e. Cut off the /6-in. quick-connect terminal from red transformer wire. f. Strip red wire /8 in. and secure factory-supplied /4-in. quick-connect terminal. g. Connect red transformer wire connector to ALS-M wire connector labeled TRANS ASSY. h. Connect ALS-M wire connector labeled DOOR SWITCH or SEC to LH furnace control SEC- terminal. i. Route -wire ALS-M connector PL8 through: (.) Strain relief bushing previously installed in 7/8-in. hole in right side of blower shelf. 4

15 (.) Gas control compartment of LH furnace. (.) Snap bushings previously installed between furnaces into gas control compartment of RH furnace. 4. Install RH furnace auxiliary door switch and auxiliary limit switch harness ALS-S/ILK-. NOTE: RH furnace auxiliary limit switch harness assembly ALS-S/ILK- has door switch included. a. Drill /8-in. hole in blower housing 0 in. below blower shelf. (See Fig..) b. Position ALS-S so terminals face front of furnace. c. Secure bracket to blower housing using factory-supplied No. 6 X /4-in. LG screw. d. Relocate RH furnace junction box JB from left side to right side as shown in Fig. if JB is not at right-hand side of RH furnace. For models produced before January 995, blower door switch ILK must also be moved when JB changes location. e. Position auxiliary door switch ILK- on left side of RH furnace. f. Secure auxiliary door switch ILK- using factory-supplied No. 6 X /4-in. LG screw. g. Route -wire harness connector PL8 of ALS-S/ILK- assembly up through snap bushing in 7/8-in. hole in left side of blower shelf and into gas control compartment. h. Connect RH ALS-S connector PL8 to LH ALS-M connector PL8 that was routed through furnace casings. 5. Select identical blower speed taps at blower motor connectors in both furnaces. CAUTI: Failure to select identical blower speed taps in both furnaces can result in overheating of furnace components and possible loss of furnace operation and damage to the furnaces. 6. Dress wires to ensure they do not contact sharp or moving parts nor interfere with blower operation, removal of filters, or operation of switches. 7. Make all thermostat connections to LH furnace only. PROCEDURE CNECT ELECTRICAL PENTS COOLING WARNING: Make no connections between the R 4-vac connector in furnace and the R 4-vac connector in other furnace. Failure to follow this warning can cause a fire, personal injury, or death. When installing single- and -stage twinned outdoor units with twinned gas furnaces, it is necessary to use a field-supplied 4-vac pilot relay and a field-supplied 4/5-vac transformer as shown in Fig. to prevent overloading furnace 4/5-vac transformer. PROCEDURE 4 VENTING Refer to the Installation, Start-Up, and Operating Instructions supplied with each furnace for venting information. CAUTI: When common-venting twinned, Category I (negative pressure venting), non-condensing furnaces, excessive condensate may occur as a result of oversized vent systems. Dedicated vents and/or proper vent sizing per the furnace Installation, Start-Up, and Operating Instructions will reduce the potential for condensation. PROCEDURE 5 GAS SUPPLY PIPING NOTE: All gas connections must be made through exposed outer side of each furnace. Do not common connect any connection other than supplyand return-air ducts. Furnaces are recommended to be provided with a single shutoff valve. However, individual shutoff valves may be required by local codes or jurisdictions. Refer to Installation, Start-Up, and Operating Instructions provided with each furnace for additional gas supply information. PROCEDURE 6 ELECTRICAL SUPPLY CNECTIS NOTE: All electrical power connections must be made through exposed outer side of each furnace. Do not common connect any connection other than supply- and return-air ducts.. Each furnace shall be connected to its own 5-vac power supply. The twinning kit installation interconnects the furnaces, allowing them to operate as a single furnace. The L (black) connection to each furnace must be connected to circuit breakers connected to the same service panel 5-vac phase leg. On single-phase (residential) systems, each furnace circuit breaker should be located directly across from each other in service panel, or each furnace circuit breaker should be located on the same side of service panel, but must skip space to be connected to the same leg of the -phase power supply. On -phase (commercial) systems, each furnace circuit breaker should be located directly across from each other in service panel, or each furnace circuit breaker should be located on the same side of service panel, but must skip spaces to be connected to the same leg of the -phase power supply. The proper 5-vac phasing of furnace connections permits 4-vac transformer phasing as described below.. Phasing of the connected 4-vac transformer secondary circuits can be determined with the LED status of both furnaces. See furnace Installation, Start-Up and Operating Instructions and status code labels on blower doors. The furnaces transformers black leads should be connected to PR connectors and white leads to PR connectors on controls. If or both LEDs are rapidly flashing, disconnect lead at TEST/TWIN terminal of LH furnace and observe LED at each furnace. 5

16 INDOOR THERMOSTAT W W/W R G C Y/Y Y NOTE 6 NOTE 4 NOTES:. TWO-SPEED FURNACES CAN BE USED WITH SINGLE-SPEED OUTDOOR UNITS.. TRANSFORMER = 5 VAC PRIMARY/4 VAC SECDARY/40 VA.. RELAYS = 4 VAC COILS/PILOT DUTY/NORMALLY OPEN. 4. FOR -STAGE COOLING, USE RELAY AND (FIELD-SUPPLIED) AS SHOWN. 5. USE TS WIRE LY FOR SINGLE-STAGE HEAT THERMOSTAT OPERATI IN ADAPTIVE HEATING MODE: GH-HEAT-LY SWITCH SW- IS, AND LOW-HEAT-LY SWITCH SW- IS IN BOTH FURNACES. 6. USE TS WIRE/TKR LY FOR -STAGE HEAT THERMOSTAT OPERATI IN N-ADAPTIVE HEATING MODE: GH-HEAT-LY SWITCH SW- IS, AND LOW-HEAT-LY SWITCH SW- IS IN BOTH FURNACES. 7. TWINNING JUMPERS TJ SHALL BE SET IN THE APPROPRIATE POSITIS (M AND S ) IN ACCORDANCE WITH THE START-UP AND ADJUSTMENT PROCEDURE. Y Y/Y LEFT HAND FURNACE (MAIN) RIGHT HAND FURNACE (SECDARY) COIL COIL Y/Y C G R W/W W TWIN Y/Y C G R W/W W TEST RELAY NOTE 4 RELAY NOTE 4 (FIELD SUPPLIED) NOTE C C NOTE 5 W NOTE 6 NOTE 6 4 TKR NOTE 6 TEST USE LY TWINNING KIT PARTS C-SECDARY NOTE 6 NOTE 6 TWIN TEST R-SECDARY W-SECDARY NOTES 5 & 6 TEST-SECDARY 4 VAC TRANS (FIELD SUPPLIED) NOTE 5 VAC NOTE 4 NOTE 4 C Y Y/Y C Y Y/Y OUTDOOR UNIT NO. OUTDOOR UNIT NO. Fig. Twinning Outdoor Units with Two -Stage Furnaces with Thermostat IF: a. Both LEDs are on continuously: System phasing is okay. b. One or both LEDs are rapidly flashing: (.) Line voltage polarity is reversed. (.) Reverse SEC- and SEC- in furnace with rapid flashing LED. c. One LED is off, LED is on continuously: (.) The 4-vac circuit is inoperative on furnace with LED light off. (.) Check transformers, auxiliary limits, and door switches in both furnaces and correct problem.. Reconnect lead at TWIN/TEST terminal of LH furnace and observe LED at each furnace. The LEDs will glow steady for proper phasing. PROCEDURE 7 START-UP AND ADJUSTMENT Refer to Installation, Start-Up, and Operating Instructions supplied with furnace for detailed information.. Shut off all power and gas to both furnaces.. Position TWINNING JUMPERS TJ on furnace controls. (See Fig. 4.) a. The LH furnace control TWINNING JUMPER TJ MUST remain in the M position. b. The RH furnace control TWINNING JUMPER TJ MUST be moved to the S position. 6 A075