MORTEX
PRODUCTS
INC
FORT
WORTH,
TX
76106
Page
11
Terminal
Connection
Color
Wire Gauge
C
Motor Common - 24 VAC Common
Green
22
L
Supply Voltage to the Motor - 240 VAC L1
Black
18
G
Ground Connection
Green
18
N
Supply Voltage to the Motor - 240 VAC L2
White
18
1
Low Voltage Speed Tap - 24 VAC
Red
22
2
Med-Low Voltage Speed Tap - 24 VAC
Orange
22
3
Medium Voltage Speed Tap - 24 VAC
White
22
4
Med-High Voltage Speed Tap - 24 VAC
Blue
22
5
High Voltage Speed Tap - 24 VAC
Black
22
Table 1: Constant Torque Motor Terminal Connections
Heater Element Is Not On
Check for 240 VAC between each of the heater elements. If
240 VAC is present, check the current draw on each heater. If
there is 200 – 250 VAC across the heaters but a heater is not
drawing the proper current or is showing almost no current
draw check the limit for that heater. If the limit is good but
there still is no current flow then, check to see if the heater is
defective.
The heater amps are as follows:
4 kW Heater = 16.7 amps
5 kW Heater = 20.8 amps
6 kW Heater = 25.0 amps
The heater design is as follows:
The 6 kW model has one 6 kW heater element.
The 8 kW model has one heater with two 4 kW elements.
The 10 kW model has one heater with two 5 kW elements
The 12 kW model has one heater two 6 kW elements.
The 15 kW model has one heater with two 5 kW elements (top
heater) and one heater with one 5 kW element (bottom
heater).
The 20 kW model has one heater with two 5 kW elements (top
heater) and one heater with two 5 kW elements (bottom
heater).
If 240 VAC is not present at the heater element but there is
240 VAC present between the load terminal of the heater
contactor check for a broken wire or bad connection.
If 240 VAC is not present at the heater element, the load
terminal of the heater contactor but is present between the line
terminals of the heater contactor; check for 24 VAC between
the A1 and A2 terminals. If 24 VAC is present then, replace
the heater contactor.
L1
L2
T1
T2
A1
A
2
Figure 11: Heater Contactor Terminal Designations
Blower Motor FLA
1/3 HP Motor – 2.8
1/2 HP Motor – 4.3
3/4 HP Motor – 6.8
Replacing the Blower
1.
Follow the instructions exactly as shown in Start Up and
Shutdown Section in this manual to properly shutdown
this appliance.
2.
Remove furnace lower front door and switch furnace
circuit breaker(s) to “OFF”.
3.
Disconnect the plastic wire plug that has the wires that
goes to the motor terminals from the control box.
4.
Remove the two screws on the right side of the blower
mounting plate.
5.
Slide the blower out of the blower compartment and set
on the floor.
6.
Remove the wire connectors from the motor terminals.
7.
Remove the blower motor from the mounting bracket by
removing the screw that secure the blower motor to the
bellyband.
8.
Insert the new blower housing into the blower mounting
bracket and secure to the bellyband with the screw. Make
sure the arms are located in the proper place so the motor
is not at an angle.
9.
Connect the wires connectors to the motor terminals so
the wires are connected to the same terminals on the new
motor as they were on the previous motor.
10.
Slide the blower assembly into the blower deck and insert
the two screws on the mounting bracket.
11.
Connect the male pin plug to the female pin plug on the
control box.
12.
Replace the control box door and switch the circuit
breakers to ON.
13.
Replace the front door.
14.
Follow the instructions exactly as shown in Start Up and
Shutdown Section in this manual to properly start up this
appliance.
15.
Set the thermostat to the desired temperature.
Figure 12: Blower Mounting Plate Screw Locations
To avoid personal injury take precautions not to come into
contact with non-insulated electrical components.
Avoid wearing loose clothing or any items that can come in
contact with moving parts, such as the blower wheel. This
can cause serious personal injury.
