Thermo Pride CDX1-100N Installation And Operation Manual page 32

All installations and services must be performed by qualified service personnel.
a. A separate power supply circuit with over current protection and a disconnect switch must be
provided. The minimum fuse or circuit breaker size is 20 amp.
b. All CHX1 and CDX1 Series furnaces are supplied with a fuse disconnect switch box to be mounted on
the outside surface of the right or left side casing so a fuse disconnect can be mounted on the
furnace. Make the 115 volt supply connection in this junction box. A green screw and a strain relief are
provided in order to connect the power supply ground wire and provide strain relief for the 115 volt
power leads from the furnace in the fuse disconnect box. A disconnect switch can be field mounted on
the 2x4 box provided. If not, the disconnect switch must be located reasonably close to and within
sight of the furnace.
NOTICE: The hot surface igniter and operation of this furnace depends on correct polarity. The hot leg of
the supply circuit must be connected to the black line lead and the common leg to the white line lead in
the field mounted junction box. The hot leg must pass through the disconnect switch in all cases to
prevent the hazard of electrical shock when servicing.
IMPORTANT: The furnace must be grounded in accordance with local codes and with the National
Electrical Code (ANSI/NFPA NO. 70 or latest edition) when an external electrical source is utilized.
2. ELECTRONIC AIR CLEANER (EAC) AND HUMIDIFIER INSTALLATION
The ignition module on this furnace has designated terminals to control the operation of an electronic air
cleaner and/or humidifier. These terminals provide line voltage (110-20VAC) for the control of these
accessories. (See Figure 21). NOTICE: It is important to confirm that the operating voltage of the
humidifier or EAC being installed matches the output of this control. If not, a field supplied relay or
transformer may be necessary to provide the proper control and supply voltage for the accessory being
installed. See the manufacturers instructions for the humidifier or EAC for additional instructions.
3. THERMOSTAT CONNECTIONS AND ANTICIPATOR SETTING
NOTICE: For two-stage thermostat wire connectors see wire diagram page 44.
thermostat with two-stage operation connect W from thermostat to W1 on control. W2 on control board is
not used. Thermostat shunt on control board (Fig. 21) will need to be moved to single t'stat. In this
configuration the furnace will light and burn on low fire for 10 minutes (5 minutes optional). If thermostat
has not been satisfied in 10 minutes the control will step up to high fire until thermostat is satisfied. If the 5
minutes option is desired turn dip switch S1-3 (Fig. 21) off.
Proper control of the indoor temperature can only be achieved if the thermostat is calibrated to the heating
and/or cooling cycle. A vital consideration of this calibration is related to the thermostat heat anticipator.
The proper thermostat heat anticipator setting is 0.4 AMPS for furnace operation only. To increase length
of cycle, increase setting of heat scale; to decrease length of cycle, decrease setting of heat scale.
Anticipators for the cooling operation are generally pre-set by the thermostat manufacturer and require no
adjustment.
Anticipators for the heating operation are of two types, pre-set and adjustable. Those that are pre-set will
not have an adjustment scale and are generally marked accordingly.
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For single-stage