Installation Instructions

Installation Instructions Twinning Kit For HSI Single- and -Speed Upflow Non-ondensing and Single-Speed ondensing Gas Furnaces KGATW040HSI NOTE: Read the entire instruction manual before starting the installation. This symbol indicates a change since the last issue. INDEX SAFETY ONSIDERATIONS... ELETROSTATI DISHARGE (ESD) PREAUTIONS... INTRODUTION... DESRIPTION AND USAGE... INSTALLATION...- SETION I: Models 58PAV, 58WAV, 8KAV, 95AV, 480BAV, and GBAAV Upflow Single-Speed Non-ondensing HSI Furnaces...4- Install Furnaces...4-5 onnect Electrical omponents Heating...5-8 onnect Electrical omponents ooling...8 Venting...8 Gas Supply Piping...9 Electrical Supply onnections...9 Start-Up and Adjustment...9 Sequence of Operation...0 onnection Diagram for Twinned Single-Speed Non-ondensing Furnaces... Schematic Diagram for Twinned Single-Speed Non-ondensing Furnaces... SETION II: Models 58TUA, 58UXT, 0AAV, and 0JAV Upflow -Speed Non-ondensing HSI Furnaces...-0 Install Furnaces...-4 onnect Electrical omponents Heating...4-5 onnect Electrical omponents ooling...5 Venting...5 Gas Supply Piping...5 Electrical Supply onnections...5-6 Start-Up and Adjustment...7 Sequence of Operation...8 onnection Diagram for Twinned -Speed Non-ondensing Furnaces...9 Schematic Diagram for Twinned -Speed Non-ondensing Furnaces...0 SETION III: Models 58MA, 58MSA, 58MXA, 40MAV, 45MAV, 50MAV, and 490AAV Upflow Single-Speed ondensing HSI Furnaces...- Install Furnaces... onnect Electrical omponents Heating...-6 onnect Electrical omponents ooling...7 Venting...7 Gas Supply Piping...7 ondensate Drain onnections...7 Electrical Supply onnections...7 Start-Up and Adjustment...9 Sequence of Operation...9 onnection Diagram for Twinned Single-Speed ondensing Furnaces...0 Schematic Diagram for Twinned Single-Speed ondensing Furnaces... Form: AG-GATW-07 ancels: AG-GATW-06 Printed in U.S.A. 6-96 atalog No. 9-GA-TW7

SAFETY ONSIDERATIONS 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, and AUTION. 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. AUTION is used to identify unsafe practices which would result in minor personal injury or product and property damage. AUTION: Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. ELETROSTATI DISHARGE (ESD) PREAUTIONS AUTION: 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.. Disconnect all power to the furnace. DO NOT TOUH THE ONTROL OR ANY WIRE ONNETED TO THE ONTROL PRIOR TO DISHARGING YOUR BODY S ELETROSTATI HARGE 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. INTRODUTION IMPORTANT: Only the furnace sizes listed in Tables,, and 4 can be twinned. Both furnaces must have the same product number, including heating and cooling sizes, to achieve correct operation. This furnace twinning kit Part No. KGATW040HSI permits connection of upflow, single-speed, non-condensing furnaces (See Fig. and.); upflow, -speed, non-condensing, -stage heat capacity furnaces (See Fig. and.); or upflow, single-speed, fixed-heat capacity, condensing furnaces (See Fig. 6, 7, and 8.) to operate as a single unit on the same duct work. The kit is applicable only to upflow furnaces listed in Tables,, and 4. 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.

DESRIPTION 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, -speed, non-condensing, -stage heat capacity, HSI furnaces as shown in Table ; or upflow, single-speed, fixed-heat capacity, HSI condensing furnaces as shown in Table 4. Refer to the appropriate section for your furnaces. SETION I: Models 58PAV, 58WAV, 8KAV, 95AV, 480BAV, and GBAAV Upflow Single-Speed Non-ondensing HSI Furnaces Single-Stage Heat with Single-Stage Gas-Heat Thermostat Two-Stage Heat with -Stage Gas-Heat Thermostat SETION II: Models 58TUA, 58UXT, 0AAV, and 0JAV Upflow -Speed Non-ondensing HSI Furnaces Two-Stage Heat with Single-Stage Gas-Heat Thermostat Two-Stage Heat with -Stage Gas-Heat Thermostat SETION III: Models 58MA, 58MSA, 58MXA, 40MAV, 45MAV, 50MAV, and 490AAV Upflow Single-Speed ondensing HSI Furnaces Single-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.,, or 6.) 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 -speed, 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. Table Kit ontents DESRIPTION PART NO. QUANTITY Foam Strip 596-0 4 Rating Plate 484-70 Relay and Harness Assembly (TKR) 0770-0 Wiring Label Schematic Diagram (Single-Speed Non-ondensing) 867-0 Wiring Label onnection Diagram (Single-Speed Non-ondensing) 866-0 Wiring Label Schematic Diagram (-Speed Non-ondensing) 0-40 Wiring Label onnection Diagram (-Speed Non-ondensing) 0-40 Wiring Label Schematic Diagram (ondensing) 865-0 Wiring Label onnection Diagram (ondensing) 864-0 Auxiliary Limit Switch Harness Master Furnace (ALS-M) 077-70 Auxiliary Door Switch/Limit Switch Harness Slave Furnace (ALS-S/ILK-) 0777-70 Sheet Metal Screw No. 6 X /4-in. LG 7 /4-in. Quick-onnect Wire Terminal /4-in. Quick-onnect Wire Tie HY76TB5 Snap Bushing HY9NH089 Strain Relief Bushing HW60ZW50 Installation Instructions AG-GATW-07 INSTALLATION NOTE: The furnace installed on the left-hand (LH) side will be referred to as the MASTER or LH furnace, and the furnace installed on the right-hand (RH) side as the SLAVE or RH furnace throughout these instructions.

SETION I: MODELS 58PAV, 58WAV, 8KAV, 95AV, 480BAV, AND GBAAV UPFLOW SINGLE-SPEED NON-ONDENSING HSI FURNAES PROEDURE INSTALL FURNAES 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 by reversing item.a. and b.. 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. 4. 5. 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. 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.. onnect return- and supply-air ducts to furnaces. Seal duct connections to prevent air leakage. JUNTION BOX JUNTION BOX AUXILIARY BLOWER DOOR SWITH BLOWER DOOR SWITH BLOWER DOOR SWITH TKR RELAY 0 TWIN/ TEST ONNETION AUXILIARY LIMIT SWITHES NOTE: Two-speed units shown. Single-speed units have only pressure switch and appearance of control will differ. Fig. Twinning Kit Installed On Non-ondensing Furnaces A957 4

AIRFLOW MASTER OR LH FURNAE 8 6 6 F D A FLUE OLLARS D 6 AIRFLOW SLAVE OR RH FURNAE 6 9 OUTLET 6 9 7 8 7 8- IN. DIA HOLE POWER ENTRY 7 8-IN. DIA HOLE LOSURE AESSORY 4-IN. DIA HOLE GAS ENTRY -IN.DIA HOLE THERMOSTAT WIRE ENTRY 5 8 5 6 8 5 6 5 8 6 5 6 8 7 8-IN. DIA HOLE LOSURE, POWER ENTRY -IN. DIA HOLE LOSURE R.H. GAS ENTRY 7 8-IN. DIA HOLE LOSURE, AESSORY -IN. DIA HOLE LOSURE, THERMOSTAT WIRE ENTRY 4 4 SIDE INLET 4 6 4 5 6 BOTTOM INLET 6 E E 6 INLET INLET Fig. Dimensional Drawing For Twinned Single-Speed Non-ondensing Furnaces A95 INPUT HEATING SIZE (BTUH) Table 58PAV, 58WAV, 8KAV, 95AV, 480BAV, and GBAAV Single-Speed Non-ondensing Furnace Dimensions (In.) NOMINAL OOLING SIZE (BTUH) A D E F 88,000 48,000 4-5/6 9-/8 9-/ 40-/6 0,000 48,000 4-5/6 9-/8 9-/ 40-/6 0,000 60,000 49-5/6-7/8 47-/6,000 48,000 4-5/6 9-/8 9-/ 40-/6,000 60,000 49-5/6-7/8 47-/6 54,000 60,000 49-5/6-7/8 47-/6 NOTE: This kit applies to the above furnaces with date codes of 594 and later. 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. PROEDURE ONNET ELETRIAL PONENTS 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. NOTE: The following attachment allows both furnaces to operate as furnace in gas heat mode as determined by single-stage thermostat 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. onnect TKR white wire labeled W from TKR to LH furnace control thermostat connection W. c. onnect TKR black wire labeled from TKR to LH furnace control thermostat connection 4V. d. onnect 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. 5

BOTTOM LOSURE PANEL FRONT FILLER PANEL Fig. Removing Bottom losure Panel A9047 6 REMOVE 7 8-IN. DIA AESSORY HOLE LOSURE FOAM STRIPS RH FURNAE A95 Fig. 4 Location of Foam Strips and Holes for Removal (.) Gas control compartment of LH furnace. Fig. 5 Attaching Furnaces Together A966 (.) Snap bushings previously installed between furnaces. (See Fig. 4.) f. onnect TKR red wire labeled R-SLAVE from TKR to RH furnace control thermostat connection R. g. onnect TKR white wire labeled W-SLAVE from TKR to RH furnace control thermostat connection W. h. onnect TKR black wire labeled -SLAVE from TKR to RH furnace control thermostat connection 4V. i. onnect TKR yellow wire labeled TEST SLAVE from LH furnace control TEST terminal to RH furnace control TEST terminal. NOTE: ALL thermostat connections are to be made to LH furnace control ONLY.. Modify TKR wiring to provide desired furnace operation. The twinning kit can be used for single-stage or -stage heating operation. Single-Stage Heat with Single-Stage Gas-Heat Thermostat (Field Supplied) The attachment of TKR (item ) allows both furnaces to operate in heating mode simultaneously. See furnace Installation, Start-Up, and Operating Instructions for further details on this heating mode. Two-Stage Heat with -Stage Gas-Heat Thermostat (Field Supplied) To operate furnaces in -stage heating mode when a -stage thermostat controls the staging, modify TKR wiring as follows. This modification 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. a. Disconnect TKR white wire labeled W from the LH furnace control thermostat connection W. b. ut off terminal of TKR white wire labeled W and strip /4 in. c. onnect -stage thermostat W connection to TKR white wire labeled W. NOTE: ALL other -stage thermostat connections are to be made to LH furnace control ONLY. 6

R G L L 4 TKR RELAY ONTROL MOUNTING BRAKET 4 W 4 V ON OFF 4 W/W Y/Y HUM TWIN TEST LED SE- SE- PR HI-OOL HI-GAS -HEAT LO-GAS -HEAT FU 7 8 9 4 5 6 0 7 8 9 4 5 6 MASTER SLAVE PR EA- EA- PARK ONTROL Fig. 6 Twinning Kit Relay Mounted On ontrol Mounting Bracket For LH Furnace (Two-Stage ontrol Shown) A955 4. 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 SE- connection. e. ut 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. onnect red transformer wire connector to ALS-M wire connector PL7 labeled TRANS ASSY. h. onnect ALS-M wire connector labeled DOOR SWITH or SE to LH furnace control SE- 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. 5. Install RH furnace auxiliary door switch and auxiliary limit switch harness ALS-S/ILK-. NOTE: RH furnace (SLAVE) 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. 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. onnect RH ALS-S connector PL6 to LH ALS-M connector PL6 that was routed through furnace casings. 6. Select identical blower motor speed taps at control center motor connectors in both furnaces. 7

W NOTE W/W R G NOTE:. SEE WIRING INSTRUTIONS FOR -STAGE HEAT USING -STAGE HEATING THERMOSTAT.. FOR -STAGE OOLING, USE RELAY AND (FIELD SUPPLIED) AS SHOWN.. TRANSFORMER=5 VA PRIMARY/4 VA SEONDARY/40 VA. 4. RELAYS = 4 VA OILS/PILOT DUTY/NORMALLY OPEN. Y/Y Y NOTE INDOOR THERMOSTAT NOTE OIL OIL Y/Y G R W/W W Y/Y G R W/W W TWIN TWIN NOTE TEST RELAY RELAY NOTE TEST (FIELD B SUPPLIED) L K TKR NOTE 4 LEFT HAND FURNAE (MASTER) 4 RIGHT HAND FURNAE (SLAVE) 4 VA TRANS (FIELD SUPPLIED) 5 VA NOTE Y Y OUTDOOR UNIT NO. OUTDOOR UNIT NO. Fig. 7 Twinning Single-Speed Outdoor Units with Single-Speed Furnaces with Thermostat A9658 AUTION: 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. 7. Dress wires to ensure they do not contact sharp or moving parts nor interfere with blower operation, removal of filters, or operation of switches. 8. Make all thermostat connections to LH furnace only. PROEDURE ONNET ELETRIAL PONENTS OOLING 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 relay and a field-supplied 4/5-vac transformer as shown in Fig. 7 to prevent overloading furnace 4/5-vac transformer. PROEDURE 4 VENTING Refer to Installation, Start-Up, and Operating Instructions supplied with each furnace for venting information. AUTION: When common-venting twinned, ategory 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. 8

PROEDURE 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. PROEDURE 6 ELETRIAL SUPPLY ONNETIONS 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. (.) Reverse SE- and SE- in LH furnace. b. One or both LEDs are rapidly flashing: (.) Line voltage polarity is reversed. (.) orrect line voltage polarity on furnace(s) with rapidly flashing LED. c. One LED is off, LED is on continuously: (.) The 4-vac circuit is inoperative on furnace with LED light off. (.) heck 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. PROEDURE 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. 8.) 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. Attach rating plate to LH furnace adjacent to furnace rating plate. 6. Turn on power and gas to both furnaces. 7. Reinstall blower access doors on both furnaces. 8. 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 cooling blower. d. ooling thermostat R-to-G-and-Y for single-speed cooling blower. 9. Reinstall control doors on both furnaces. 0. Instruct user in operation of furnace and thermostat. 9

BLOWER OFF DELAY SWITH OR JUMPER WIRE TEST/TWIN G R Y W om 4V HUM 4-VA THERMOSTAT LEAD TERMINALS LED OPERATION & DIAGNOSTI LIGHT SE- -AMP FUSE OOL HEAT 4-VA TRANSFORMER SE- SPARE BLOWER SPEED SELETION TERMINALS SPARE 5-VA (L) POWER SUPPLY 5-VA (L) NEUTRAL ONNETION Fig. 8 Single-Stage Furnace ontrol A958 PROEDURE 8 SEQUENE OF OPERATION See Fig. 9 and 0 for single-speed non-condensing furnace twinning connection and schematic wiring diagrams while reviewing the sequence of operation. Twinning operation is controlled by LH or MASTER furnace. The 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.. 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. 0

PB BLOWER OFF DELAY SELETION HART 90 SE 5 SE 80 SE 5 SE GVR HSIR IDR BLWR 0 VA L PR PL PL BLOWER OFF DELAY HI/LO RELAY TEST/TWIN BLOWER SPEED SELET PL 6 5 4 9 8 7 G R Y W OM 4V HUM LED SE- SE- FU L PR 4 VA-A FUSE OOL SPARE- HEAT SPARE- EA-.0 AMP PL5 EA- HSI SW SW NOTES #9 AND #4 NOTES #0 AND #4 NOTE #5 PRS NOTE #8 DSS 4 BLOWER SW G NO DSS PRS OFF R NOTE #5 LGPS NOTE PB TKR DELAY Y #5 NOTE # SW W LGPS (NOT ON ALL MODELS) OM 4V BLOWER OFF DELAY HUM SELETION HART TEST/TWIN NOTE #5 LED FRS 90 SE -M -P FL 5 SE LS FRS -M -P LS FL GV FRS 80 SE PL GV FSE - NOTE #5 5 SE 6 5 4 FSE 9 8 7 - FRS NOTE #8 PL6 GVR NOTE #5 ILK- ALS-S SE- SE- SLAVE NOTE #8 HI/LO OR RH (HI) RELAY ALS-M PL7 FURNAE 4 VA-A () NOTE # FU FUSE NOTE # () OOL SPARE- (HI) OL BLOWER OL (MED-HI) HSIR IDR BLWR SPEED (MED-HI) NOTE #7 START SELET TRAN HEAT SPARE- NOTE #7 START L EA- (MED-LO) PL (MED-LO) PL PR (LO) BLWM 0 VA BLWM EA- (LO) L PR () () AP OM.0 AMP AP TRAN HSI PL5 JB FUSED DISONNET SWITH (WHEN REQ D) NOTE #4 NOTE # (NOT ON ALL MODELS) MASTER OR LH FURNAE IDM ILK JB FUSED DISONNET SWITH (WHEN REQ D) NOTE #4 FU IDM ILK FU LEGEND ALS-M MASTER AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N..) ALS-S SLAVE AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N..) BLWR BLOWER MOTOR RELAY, SPST-(N.O.) BLWM BLOWER MOTOR, - OR 4-SPEED, PERMANENT-SPLIT-APAITOR AP APAITOR DSS DRAFT SAFEGUARD SWITH, AUTO-RESET, SPST-(N..) EA- ELETRONI AIR LEANER ONNETION (5 VA.0 AMP MAX.) EA- ELETRONI AIR LEANER ONNETION (MON) FL FUSIBLE LINK FRS FLAME ROLLOUT SW. -MANUAL RESET, SPST-(N..) FSE FLAME-PROVING SENSOR ELETRODE FU FUSE, AMP, AUTOMOTIVE BLADE TYPE, FATORY INSTALLED FU FUSE OR IRUIT-BREAKER URRENT-INTERRUPT DEVIE (FIELD INSTALLED & SUPPLIED) GV GAS VALVE-UNDANT OPERATORS GVR GAS VALVE RELAY, DPST-(N.O.) HI/LO BLOWER MOTOR SPEED HANGE RELAY, SPDT HSI HOT SURFAE IGNITER (5 VA) HSIR HOT SURFAE IGNITER RELAY, SPST-(N.O.) HUM 4VA HUMIDIFIER ONNETION (0.5 AMP. MAX.) IDM INDUED DRAFT MOTOR, SHADED-POLE IDR INDUER MOTOR RELAY, SPST-(N.O.) ILK BLOWER DOOR INTERLOK SWITH, SPST-(N.O.) ILK- SLAVE AUX. BLOWER DOOR INTERLOK SWITH, SPST-(N.O.) JB JUNTION BOX LED LIGHT-EMITTING DIODE FOR STATUS ODES LGPS LOW GAS-PRESSURE SWITH, SPST (N.O.) LS LIMIT SWITH, AUTO RESET, SPST(N..) OL AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SWITH, SPST-(N..) PB PRINTED IRUIT BOARD PL 9-IRUIT ONNETOR PL -IRUIT ONNETOR PL -IRUIT IDM ONNETOR PL5 -IRUIT HSI ONNETOR PL6 -IRUIT TWINNING KIT ONNETOR PL7 -IRUIT TWINNING KIT IN-LINE SPLIE PRS PRESSURE SWITH, SPST-(N.O.) TEST / TWIN PONENT TEST & TWIN TERMINAL TKR TWINNING KIT RELAY, SPST-(N.O.) TRAN TRANSFORMER-5VA / 4VA 866-0 REV. B JUNTION UNMARKED TERMINAL PB ONTROL TERMINAL FATORY WIRING (5VA) FATORY WIRING (4VA) FIELD WIRING (5VA) FIELD AESSORY WIRING (4VA) FIELD WIRING TERMINAL, NOTE #4 FIELD GROUND EQUIPMENT GROUND FIELD SPLIE PLUG REEPTALE WIRES PASSING THROUGH HOLES IN ASINGS FROM LH TO RH FURNAE. NOTES: Fig. 9 onnection Diagram for Twinned Single-Speed Non-ondensing Furnaces. If any of the original equipment wire is replaced, use wire rated for 05 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-HI) is not on all motors. 8. Passes through holes in casings. ALS-S & ILK- are located in the slave furnace blower compartment. 9. Make thermostat connections to only the LH furnace. 0. Make no thermostat connections to RH furnace.. Blower-on delay, gas heating 40 seconds, cooling or heat pump seconds.. 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-for-ignition. ontrol will auto-reset after three hours. 4. Some models may have spade quick connect terminals. 5. Factory onnected when LGPS not used. A95

867-0 REV. B MAKE THERMOSTAT ONNETIONS TO ONLY THE LH FURNAE TO 5VA FIELD DISONNET NOTE #4 L L ILK L BLWR HSIR EQUIPMENT GROUND HI/LO EA- EA- MASTER OR LH FURNAE SPARE- HEAT SPARE- OOL LO BLWM MED LO MED HI NOTE #7 START HI OL NOTE # SHEMATI DIAGRAM (NATURAL GAS & PROPANE) AP L MAKE NO THERMOSTAT ONNETIONS TO RH FURNAE ILK L TO 5VA FIELD DISONNET NOTE #4 L L EQUIPMENT GROUND BLWR HSIR EA- HI/LO EA- SPARE- HEAT SPARE- OOL SLAVE OR RH FURNAE LO BLWM MED LO MED HI NOTE #7 START HI OL NOTE # AP L ALS-M PL7 IDR TEST/TWIN FU NOTE #6 HUM R W HSIR IDR PL HSI PL5 PR 5VA PR TRAN 4VA SE- GVR- BLWR SE- HI/LO GVR 4 7 PL NOT USED FRS FRS LS NOTE # PL DSS PRS IDM LGPS FL PASSES THROUGH HOLES IN ASINGS IDR TEST/TWIN FU NOTE # HUM R W HSIR NOTE #6 IDR PL HSI PL5 PR 5VA PR TRAN 4VA SE- GVR- BLWR SE- HI/LO GVR 4 7 PL NOT USED PL IDM FRS FRS LS NOTE # DSS PRS LGPS FL TKR 4 NOTE # -P GV PU GVR- - PU GVR- -M Y NOTE #5 8 Y 8 OM 4V G 5 6 9 FSE Fig. 0 Schematic Diagram for Twinned Single-Speed Non-ondensing Furnaces A954 NOTE # -P GV - -M NOTE #5 G 5 6 FSE NOTE # LEGEND ALS-M MASTER AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N..) ALS-S SLAVE AUX. LIMIT SW., OVERTEMP-MANUAL RESET, SPST-(N..) BLWR BLOWER MOTOR RELAY, SPST-(N.O.) BLWM BLOWER MOTOR, - OR 4-SPEED, PERMANENT-SPLIT-APAITOR AP APAITOR PU MIROPROESSOR AND IRUITRY DSS DRAFT SAFEGUARD SWITH, AUTO-RESET, SPST-(N..) EA- ELETRONI AIR LEANER ONNETION (5 VA.0 AMP MAX.) EA- ELETRONI AIR LEANER ONNETION (MON) FL FUSIBLE LINK FRS FLAME ROLLOUT SW. -MANUAL RESET, SPST-(N..) FSE FLAME-PROVING SENSOR ELETRODE FU FUSE, AMP, AUTOMOTIVE BLADE TYPE, FATORY INSTALLED NOT USED NOT USED OM 4V GV GAS VALVE-UNDANT OPERATORS GVR GAS VALVE RELAY, DPST-(N.O.) - = VALVE - = HUMIDIFIER HI/LO BLOWER MOTOR SPEED HANGE RELAY, SPDT HSI HOT SURFAE IGNITER (5 VA) HSIR HOT SURFAE IGNITER RELAY, SPST-(N.O.) HUM 4VA HUMIDIFIER ONNETION (0.5 AMP. MAX.) IDM INDUED DRAFT MOTOR, SHADED-POLE IDR INDUER MOTOR RELAY, SPST-(N.O.) ILK BLOWER DOOR INTERLOK SWITH, SPST-(N.O.) ILK- SLAVE AUX. BLOWER DOOR INTERLOK SWITH, SPST-(N.O.) PL6 ALS-S NOTE #8 9 ILK- NOT USED NOT USED LED LIGHT-EMITTING DIODE FOR STATUS ODES LGPS LOW GAS-PRESSURE SWITH, SPST (N.O.) LS LIMIT SWITH, AUTO RESET, SPST(N..) OL AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SW., SPST (N..) PB PRINTED IRUIT BOARD PL 9-IRUIT ONNETOR PL -IRUIT ONNETOR PL -IRUIT IDM ONNETOR PL5 -IRUIT HSI ONNETOR PL6 -IRUIT TWINNING KIT ONNETOR NOTES:. If any of the original equipment wire is replaced use wire rated for 05 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-HI) is not on all motors. 8. ALS-S & ILK- are located in the slave 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-for-ignition. ontrol will auto-reset after three hours.. Some models may have spade quick-connect terminals.. Factory connected when LGPS not used. LEGEND ONT... PL7 -IRUIT TWINNING KIT IN-LINE SPLIE PRS PRESSURE SWITH, SPST-(N.O.) TEST / TWIN PONENT TEST PIN AND TWIN ONNETOR TKR TWINNING KIT RELAY, SPST-(N.O.) TRAN TRANSFORMER-5VA / 4VA JUNTION UNMARKED TERMINAL PB ONTROL TERMINAL FATORY WIRING (5VA) FATORY WIRING (4VA) FIELD AESSORY WIRING (4VA) ONDUTOR ON PB FIELD WIRING TERMINAL, NOTE # FIELD GROUND EQUIPMENT GROUND FIELD SPLIE PLUG REEPTALE

SETION II: MODELS 58TUA, 58UXT, 0AAV, AND 0JAV UPFLOW -SPEED NON-ONDENSING HSI FURNAES PROEDURE INSTALL FURNAES 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 by reversing item.a. and b.. 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. 4. 5. 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. AIRFLOW MASTER OR LH FURNAE 8 6 6 F D A FLUE OLLARS D 6 AIRFLOW SLAVE OR RH FURNAE 6 9 OUTLET 6 9 7 8 7 8- IN. DIA HOLE POWER ENTRY 7 8-IN. DIA HOLE LOSURE AESSORY 4-IN. DIA HOLE GAS ENTRY -IN.DIA HOLE THERMOSTAT WIRE ENTRY 5 8 5 6 8 5 6 5 8 6 5 6 8 7 8-IN. DIA HOLE LOSURE, POWER ENTRY -IN. DIA HOLE LOSURE R.H. GAS ENTRY 7 8-IN. DIA HOLE LOSURE, AESSORY -IN. DIA HOLE LOSURE, THERMOSTAT WIRE ENTRY 4 4 SIDE INLET 4 6 4 5 6 BOTTOM INLET 6 E E 6 INLET INLET Fig. Dimensional Drawing For Twinned -Speed Non-ondensing Furnaces A95 Table 58TUA, 58UXT, 0AAV, and 0JAV -Speed Non-ondensing Furnace Dimensions (In.) INPUT HEATING SIZE (BTUH) NOMINAL OOLING SIZE (BTUH) A D E F 80,000 48,000 4-5/6 9-/8 9-/ 40-/6 00,000 48,000 4-5/6 9-/8 9-/ 40-/6 00,000 60,000 49-5/6-7/8 47-/6 0,000 48,000 4-5/6 9-/8 9-/ 40-/6 0,000 60,000 49-5/6-7/8 47-/6,000 60,000 49-5/6-7/8 47-/6

. onnect 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. PROEDURE ONNET ELETRIAL PONENTS 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.. 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. onnect black wire terminal labeled to LH furnace control thermostat connection 4. e. onnect 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. onnect black wire terminal labeled -SLAVE to RH furnace control thermostat connection 4. h. onnect yellow wire terminal labeled TEST SLAVE to RH furnace control TWIN/TEST terminal. i. 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. onnect TKR white wire labeled W from TKR to LH furnace control thermostat connection W. c. onnect TKR black wire labeled from TKR to LH furnace control thermostat connection 4. d. onnect 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. onnect TKR red wire labeled R-SLAVE from TKR to RH furnace control thermostat connection R. g. onnect TKR white wire labeled W-SLAVE from TKR to RH furnace control thermostat connection W/W. h. onnect TKR black wire labeled -SLAVE from TKR to RH furnace control thermostat connection 4V. i. onnect TKR yellow wire labeled TEST SLAVE 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 SE- connection. e. ut 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. 4

g. onnect red transformer wire connector to ALS-M wire connector labeled TRANS ASSY. h. onnect ALS-M wire connector labeled DOOR SWITH or SE to LH furnace control SE- 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. (.) 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 (SLAVE) 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. onnect 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. AUTION: 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. PROEDURE ONNET ELETRIAL PONENTS OOLING 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 relay and a field-supplied 4/5-vac transformer as shown in Fig. to prevent overloading furnace 4/5-vac transformer. PROEDURE 4 VENTING Refer to the Installation, Start-Up, and Operating Instructions supplied with each furnace for venting information. AUTION: When common-venting twinned, ategory 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. PROEDURE 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. PROEDURE 6 ELETRIAL SUPPLY ONNETIONS 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. 5

W NOTE 6 W/W R G NOTE:. TWO-SPEED FURNAES AN BE USED WITH SINGLE-SPEED OUTDOOR UNITS.. TRANSFORMER = 5 VA PRIMARY/4 VA SEONDARY/40 VA.. RELAYS = 4 VA OILS/PILOT DUTY/NORMALLY OPEN. 4. FOR -STAGE OOLING, USE RELAY AND (FIELD-SUPPLIED) AS SHOWN. 5. FOR SINGLE-STAGE HEAT THERMOSTAT OPERATION. 6. FOR -STAGE HEAT THERMOSTAT OPERATION. Y/Y Y NOTE 4 INDOOR THERMOSTAT LEFT HAND FURNAE (MASTER) RIGHT HAND FURNAE (SLAVE) OIL OIL Y/Y G R W/W W Y/Y G R W/W W TWIN TWIN TEST RELAY RELAY NOTE TEST 4 (FIELD NOTE 5 SUPPLIED) NOTE 5 & 6 NOTE NOTE 6 USE ONLY TWINNING KIT PARTS TKR NOTE 6 4 VA TRANS (FIELD SUPPLIED) NOTE 5 VA Y Y/Y Y Y/Y NOTE 4 NOTE 4 OUTDOOR UNIT NO. OUTDOOR UNIT NO. Fig. Twinning Outdoor Units with Two -Speed Furnaces with Thermostat A967 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. (.) Reverse SE- and SE- in LH furnace. b. One or both LEDs are rapidly flashing: (.) Line voltage polarity is reversed. (.) orrect line voltage polarity on furnace(s) with rapidly flashing LED. c. One LED is off, LED is on continuously: (.) The 4-vac circuit is inoperative on furnace with LED light off. (.) heck 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. 6

PROEDURE 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..) a. The LH furnace control TWINNING JUMPER TJ MUST remain in the MASTER position. b. The RH furnace control TWINNING JUMPER TJ MUST be moved to the SLAVE position.. Determine desired furnace control operation and position set-up switches on furnace control. (See Fig..) Two-Stage Heat with Single-Stage Gas-Heat Thermostat a. Position SW switch on controls in BOTH furnaces to OFF. b. Position SW switch on controls in BOTH furnaces to OFF. c. Position SW and SW4 switches on control in BOTH furnaces to desired gas-heat blower off delay. (See furnace Installation, Start-Up, and Operating Instructions for further details.) Two-Stage Heat with -Stage Gas-Heat Thermostat a. Position SW switch on controls in BOTH furnaces to OFF. b. Position SW switch on controls in BOTH furnaces to ON. c. Position SW and SW4 switches on controls in BOTH furnaces to desired gas-heat blower off delay. (See furnace Installation, Start-Up, and Operating Instructions for further details.) 4. Attach twinning connection diagram label over existing wiring label on inside of LH furnace blower door. 5. Attach twinning schematic diagram label over existing wiring label on inside of RH furnace blower door. 6. Attach rating plate to LH furnace adjacent to furnace rating plate. 7. Turn on power and gas to both furnaces. 8. Reinstall blower access doors on both furnaces. 9. Determine furnace model. Using appropriate section below, operate furnaces through cycles in each mode to confirm correct operation by operating only the thermostat. a. Single- or -stage gas heating thermostat R-to-W/W for low-gas heat. Single-stage thermostat with adaptive heating mode causes furnace to operate in low-gas-heat mode for up to 6 minutes, and then furnace automatically switches to high-gas heat. First stage of a -stage thermostat without adaptive heating mode causes furnace to operate in low-gas-heat mode indefinitely. b. First- and second-stage of -stage heating thermostat R-to-W/W-and-W for high-gas-heat. c. Thermostat R-to-G for continuous fan or -speed cooling low-cool blower. d. ooling thermostat R-to-G-and-Y/Y for single-speed cooling blower or for -speed cooling high-cool blower. 0. Reinstall control doors on both furnaces.. Instruct user in operation of furnaces and thermostat. SET-UP SWITHES SW4 SW SW SW ON OFF 7 8 9 4 5 6 PR PR L L HI-OOL HI-GAS -HEAT EA- THERMOSTAT ONNETIONS MASTER SLAVE 4 5 6 7 8 9 0 LO-GAS -HEAT EA- PARK SE- FU SE- MASTER TWIN/TEST ONNETOR LED TWINNING JUMPER TJ SLAVE Fig. Two-Stage Furnace ontrol A954 7