035-19457-000-B-0403
3Unitary Products Group
INSTALLATION FOR DM/DF/DH 036 THRU 076,
DL/DS/DU -03 THRU -A6 PACKAGED COOLING
UNITS AND BQ 036 THRU 060, BB -03 THRU -05
PACKAGED HEAT PUMPS.
Install the fuse block accessories as follows:
NOTE: Most of the following installation procedures are
duplicates of the electric heater accessory instal-
lation procedures. Refer to ”For Heaters With A
Fuse Box” section in the installation instruction.
1. Disconnect all electrical power to the unit.
2. Remove the following panels from the basic unit.
• Heating access panel
• Heater control box cover
• Blower access panel
• Unit control box access panel
NOTE: Motor leads are held to the blower by plastic ties.
Do not disturb the ties.
3. Mount the fuse box (containing the fuse block and fuses)
inside the blower section. Attach the upper left hand
flange on the fuse box to the back of the main control
box with one screw provided.The mounting hole is
located about 6” up from the bottom of the control box in
the rounded corner of the box. Attach the bottom right
hand flange on the fuse box to the unit base, at the holes
provided, with screws provided. See Figure 2.
NOTE: If insulation grip nail fasteners on the base of the
blower section interfere with proper mounting of
the fuse box, they should be broken off.
4. Disconnect heater power wiringharness from the bottom
terminals of the unit disconnect or terminal block in the
unit control box.
5. Loosen the electrical connector holding the heater power
harness and remove the harness from the connector.
6. Open the hinged fuse box cover to gain access to the
inside. Insert the three (3) power leads from the heater
harness through the bottom hole in theright-hand side of
the fuse box and through the electrical connector. This
connector is supplied with the fuse block kit to secure the
power leads to the fuse box. Position connector so that
the connector nut is located on the outside of the fuse
box. Tighten nut.
NOTE: Wrap leads with a minimum of 3 layers of tape
where they come in contact with the connector.
NOTE: DO NOT tighten the connector clamp screws until
the leads are connected and in place.
7. Connect the three (3) power leads of the heater harness
removed in Steps 4 thru 6 to the bottom terminals of the
fuse block.
8. Insert one end of the three (3) power leads from the fuse
block kit through the top hole in the right-hand side of the
fuse box and through the electrical connector. This con-
nector is supplied with the fuse block kit to secure the
power leads to the fuse box. Position connector so that
the connector nut is located on the outside of the fuse
box. Tighten nut.
NOTE: Wrap leads with a minimum of 3 layers of tape
where they come in contact with the connector.
NOTE: DO NOT tighten the connector clamp screws until
the leads are connected and in place.
9. Insert the other end of the three (3) power leads from the
fuse block kit into the cable connector in the unit control
box.
10. Connect the three (3) power leads that were inserted in
the fuse box, to the top terminals of the fuse block.
11. Connect the three (3) power leads that were inserted in
the unit control box, to the bottom terminals of the unit
disconnect or terminal block. Refer to the wiring labels
inside of the fuse box cover for proper wiring connec-
tions.
12. Adjust all wires for the proper slack, now tighten the
screws on the connector clamp to secure in position.
13. Close fuse box cover, replace cover on the heater con-
trol box and re-install the unit panels that were removed
in Step 2.
14. Reconnect power to the unit.
Exercise care when securing the fuse box in posi-
tion to make sure that the evaporator low tempera-
ture sensor control leads are not pinched or cut. If
leads must be routed away from sheet metal
edges, visually check the control to insure its loca-
tion has not been disturbed.
