Instruction manual

c. Connect TKR black wire labeled C from TKR to LH furnace control thermostat connection COM 24V.
d. Connect yellow wire labeled TEST to LH furnace control TEST/TWIN terminal.
e. If Extension Harness was used, connect 4-wire harness to Extension Harness.
NOTE: If Extension Harness will not plug in to L/H and R/H furnaces, extension harness is installed backward. Remove extension harness and
re-install in correct orientation.
2. Install Auxillary Limit Switch (ALS-M) on L/H furnace:
a. Drill 1/8-in. hole in blower housing 12 in. below blower shelf. (See Fig. 11.)
b. Position ALS-M so reset button faces front of furnace.
c. Secure bracket to blower housing using a factory-supplied screw.
d. Disconnect red transformer wire from LH furnace control SEC-1 connection.
e. Connect red transformer wire connector to ALS-M wire connector PL7 labeled TRAN.
f. Connect orange ALS-M wire connector labeled DOOR SWITCH or SEC 1 to LH furnace control SEC-1 terminal.
g. If Extension Harness was used, connect 2-wire harness to Extension Harness
3. Install Secondary 4-wire harness on R/H furnace:
The Secondary Harness includes the Auxiliary Door Switch and Auxiliary Limit Switch. The harness is also tagged ″Secondary Furnace″ near the
plug ends of the harness.
a. Connect red wire labeled R-Secondary to RH furnace control thermostat connection R.
b. Connect white wire labeled W-Secondary to RH furnace control thermostat connection W.
c. Connect black wire labeled C-Secondary to RH furnace control thermostat connection C
OM 24V.
d. Connect yellow wire labeled TEST SECONDARY from LH furnace control TEST terminal to RH furnace control TEST terminal.
e. If the furnaces are side-by-side, route loose ends of 4-wire harness from Secondary furnace to Main furnace through snap bushings
previously installed between furnaces. (See Fig. 4.)
f. Connect Secondary 4-wire harness into 4-wire Main harness.
g. If Extension Harness was installed, connect 4-wire Secondary Harness to the Extension Harness.
4. Install Auxiliary Limit Switch, ALS-S on Secondary furnace:
a. Drill 1/8-in. hole in blower housing 12 in. below blower shelf. (See Fig. 11.)
b. Position ALS-S with terminals facing front of furnace.
c. Secure bracket to blower housing using factory-supplied screw.
Fig. 10A—TKR Relay Secured with Factory-Supplied Screws on Single-Stage Unit
A02233
TKR Relay-Secure w/2
factory-supplied screws
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