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Installation Notes
5.1
Cold Air Return
The duct can be attached to either side, rear or the bottom of the furnace.
For side return there are four 1½” (38 mm) knockouts which can be removed and used as an outline for cutting a 18” x 18” (457 mm x
457 mm) return air opening in the furnace left or right side. Mount the filter frame to the furnace over the opening with the open side
of the frame facing front. Then attach the 19” x 19” (483 mm x 483 mm) air duct to the flanges on the filter frame.
For bottom mounting, remove the screws holding the bottom plate to the furnace, discard the bottom plate and attach the filter frame
to the bottom flanges with the open side of the frame facing front.
5.2
Electrica Wiring - Power Supply
The furnaces are completely factory wired. From a separate breaker, a two-wire plus ground supply wire is required for single phase
units, and a three-wire plus ground supply wire for three phase units. The ground conductor must be firmly attached to the ground lug
in the furnace and the supply wires to the terminal block in the furnace.
NOTE: When a FK120 kit is used to supply an air cleaner and/or humidifier, a third (neutral) conductor must be brought into the
furnace.
WARNING
For all installations, we only recommend appropriate gauge good quality copper wire(s).
However, it is the electrician’s
responsibility to ensure that the wiring and connections are compliant to the latest editions of the Canadian Electrical Code
and local codes.
5.3
Connecting and Adjusting the Low Voltage Thermostat
Use only class 1 wires inside furnace compartments.
Attach thermostat wires to the low voltage terminal block located on the inside of the furnace. Follow the diagrams supplied with the
thermostat. As a general guide, remember that the R & W terminals control single stage heating; the R & Y terminals control cooling.
Single stage cooling uses “Y/Y2” as first and only stage.Two-stage cooling uses “Y1” as first stage and “Y/Y2” as second stage. Make
sure the thermostat is levelled on the wall and in appropriate location as per instructions supplied with the thermostat.
CAUTION
Before turning the furnace on, the heat anticipator in the thermostat must be properly set.
Because each installation is different an accurate reading of the current draw should be made with an AC meter. Set the meter at 2 A
range for furnaces through 20 kW, and at 4 A range for larger units.
A Set the anticipator at its highest setting.
B Disconnect the “W1” thermostat wire from the furnace low voltage terminal connections.
C Connect the AC meter between the “W1” terminal on the board and the loose “W1” wire.
D Turn the thermostat up to start the furnace and allow it to run,with all elements on, for three or four minutes.
E Read the current draw on the meter and reset the anticipator to match the meter reading.
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