ACCESSORY KIT INSTALLATION INSTRUCTIONS - UPGNET

1 Unitary Products GroupACCESSORY KIT INSTALLATION INSTRUCTIONS2TC03700124 FURNACE TWINNING CONTROL 035-14572-000 REV. A (800)For use with the following furnace models: ALL SINGLE STAGE DIRECT DRIVE BLOWER MODEL GAS FURNACES ALL DIRECT DRIVE BLOWER MODEL OIL FURNACESTWO BELT DRIVE MODEL GAS FURNACES MAY BE TWINNED WITH THE ADDITION OF ACCESSORY MODEL 2TS03700106 GENERALThis twinning control ACCESSORY allows properoperation of two furnaces when the units are installedon a common duct system in a commercial allows a greater system cfm and heating capacityto be attained than would be available from a control, shown in Figure 1.

2 Supports both singleand dual stage heating/cooling thermostats. Fansensors continuously monitor the fan motors for propersystem operation. The system shuts down if either failsto operate. DESCRIPTIONThis ACCESSORY includes the twinning control and 2blower sensor assemblies with 15 ft. wiring control uses only 24 volt field wiring electro-mechanical or electronic type roomthermostats may be applied with this twinning control,as it has no special blower sensors will properly function with anydirect drive PSC or multi-speed blower : This kit should not be applied with two SEQUENCEThe following describes the operation of a twinned furnacesystem using this control.

3 Both single stage and two stagesequences are STAGE THERMOSTAT OPERATIONFAN ONLY - When the fan switch on the room thermostat is in the "ON" position, both furnaces will receive the "G" signal, and both blowers will operate. This will allow constant airflow and will reduce air stratification within the conditioned space. Constant airflow is recommended in most commercial applications during the occupied - When the room thermostat heating circuitcloses, the control will first energize the "G" circuits in bothfurnaces to start the blowers.

4 One second later, the controlwill energize the "W" circuits in both furnaces. This willprovide total heating capacity under control of the singlestage room installing this control, disconnect electricalpower to both furnaces. Failure to cut power couldresult in electric shock or equipment control must not be installed in any locationwhere it could be exposed to water. If the controlhas been exposed to water in any way, it must notbe timer kit part no. 373-21144-001 isrequired on furnaces with 1 hp or greater blowermotors.

5 Premature motor failure can occur if thiskit is not REV. A (800)2 Unitary Products GroupWhen the room thermostat is satisfied, the "W" circuitsto both furnaces will be de-energized. The furnaceblowers will continue to operate for the standard bloweroff delay (BOD) set at the time of INSTALLATION . If thestandard BOD is set for 60 seconds, the twinningcontrol will energize the blowers for an additional - When the room thermostat cooling circuitcloses, the control will first energize the "G" circuits inboth furnaces to start the blowers.

6 One second later,the control will energize the "Y" circuit(s) to thecondensing units (either 1 or 2). This will provide totalcooling capacity under control of the single stage roomthermostat. If only one fan is sensed "ON" while athermostat signal is present, relays in the twinningcontrol close both fan (R-G) the room thermostat is satisfied, the "Y" circuitsto both condensing units will be de-energized. Thefurnace blowers will continue to operate for 65seconds, then the "G" circuits will be STAGE THERMOSTAT OPERATIONFAN ONLY - When the fan switch on the roomthermostat is in the "ON" position, both furnaces willreceive the "G" signal, and both blowers will will allow constant airflow and will reduce airstratification within the conditioned space.

7 Constantairflow is recommended in most commercialapplications during the occupied , STAGE ONE - When the room thermostatheating circuit "W1" closes, the control will firstenergize the "G" circuits in both furnaces to start theblowers. One second later, the control will energize the"W" circuit in one of the furnaces. This will provide 50%heating capacity. When first stage of the roomthermostat is satisfied, the "W" circuit to the activefurnace will be furnace blowers will continue to operate for for thestandard blower offf delay (BOD) set at the time ofinstallation.

8 If the standard BOD is set for 60 seconds,the twinning control will energize the blowers for anadditional 5 seconds. On the next heating cycle, thepreviously inactive furnace will be utilized as first will provide equal run time on both , STAGE TWO - With the system operatingon first stage, as detailed above, when the secondstage thermostat heating circuit "W2" is energized, thetwinning control will energize the "W" circuit in thesecond furnace. This will provide 100% second stage of the room thermostat is satisfied,the "W" circuit to the second stage furnace will be de-energized.

9 This will allow the system heating capacity toagain fall to 50%. The system will cycle off as detailedin stage one above. The second stage furnace usageFIGURE 1: TWINNING CONTROL2TC03700124 TWINNING CONTROLTHERMOSTATCONNECTIONS(1ST STAGEHEAT) W1(2ND STAGE HEAT W2(1ST STAGE COOL) Y1(2ND STAGE COOL) Y2(FAN) G(SUPPLY) R(COMMON) CFOR SINGLE STAGE OPERATION:HEATING: JUMPER W1-W2 COOLING: JUMPER Y1-Y2 INPUT: 24 VAC, 50-/60 HZ (FROM FURNACE 1 XFMR)OUTPUTS: 2 A MAX. (EACH FUNCT.)T'STAT ANTICIPATOR SETTING: (COM)R (24V)W (HEAT)Y (COOL)G (FAN)G (FAN)Y(COOL)W (HEAT)R (24V)C (COM)WHTBLKRED(+)(-)SEE INSTRUCTIONS FOR ELECTRICALSPECIFICATIONS OF REMOTE DEVICEFLASH 1 = FURNACE 1 FLASH 2 = FURNACE 2 FLASH 3 = BOTHFURANCE2 FURANCE1 FAN/LEDSENSORINPUTSFAN/LEDSENSORINPUTSFU RNACET'STATINPUTSFURNACET'STATINPUTSREMO TE FAULTSIGNAL OUTPUT FIGURE 2: TYPICAL TWINNED FURNACE APPLICATIONSUPPLY AIR1 OR 2 COILSRETURN AIRCOMMONRETURNPLENUMSEPARATEGAS & ELECTRICALSUPPLIESCOMMONSUPPLYPLENUM035- 14572-000 REV.)

10 A (800)Unitary Products Group3will also alternate along with the first stage unit asdetailed in Stage One , STAGE ONE - When the room thermostatcooling circuit "Y1" closes, the control will first energizethe "G" circuits in both furnaces to start the second later, the control will energize the "Y"circuit to condensing unit number will provide 50% cooling capacity. When first stageof the room thermostat is satisfied, the "Y" circuit tocondensing unit number two will be de-energized. Thefurnace blowers will continue to operate for 65seconds, then the "G" circuits will be de-energized.