Warning, Electrical system installation, Codes, specifi cations, and re- quirements – Nordyne E3 Series User Manual
Page 17: Applications and furnace installation

17
3. Install 240V supply circuit(s) and 24V wir-
ing to closet (see Figure 16 for appropriate 
locations).
4.
Position optional coil cabinet over fl oor cutout 
and secure with three or more fasteners.
5.
Position furnace onto coil cabinet and secure 
with two or more fasteners.
6.
Use optional upfl ow duct connector or fi eld 
supplied connector to attach furnace to 
overhead supply duct (see Figure 17).
ELECTRICAL SYSTEM 
INSTALLATION
WARNING:
To avoid the risk of electrical shock, 
personal injury or death, disconnect 
all electrical power to the unit before 
performing any maintenance or 
service. The unit may have more than 
one electrical power supply.
Codes, Specifi cations, and Re-
quirements
The wiring, installation, and electrical hookup 
of this furnace must comply with the National 
Electrical Code (or the Canadian Electrical Code) 
and all regulations of local authorities having 
jurisdiction. See Table 9a & 9b for minimum circuit 
ampacity, maximum over-current protection, and 
recommended wire size. See the unit wiring 
diagram for other wiring details.
Supply-circuit requirements are as follows:
Applications and Furnace 
Installation
NOTE: Remove refrigerant line knockouts in 
furnace only when installing indoor coil of an 
air conditioning or heat pump system.
Refer to instructions supplied with accessory 
equipment.
Over-the-Floor Return Air System 
(Non-Ducted)
1. If 
fl oor underneath furnace is made of com-
bustible material, locate a pan fabricated of 
non-combustible material with 1” upturned 
fl anges under furnace return air opening (see 
Figure 18). 
2.
Use optional upfl ow stand with fi lters or con-
struct a suitably braced mounting platform 
in closet (see Figure 17 or 18).
3. Install 240V supply circuit(s) and 24V wir-
ing to closet (see Figure 16 for appropriate 
locations).
4. Position optional coil cabinet onto upfl ow
stand or mounting platform and secure with 
three or more fasteners.
5.
Position furnace in upfl ow mode onto coil cabi-
net and secure with two or more fasteners.
6.
Use optional upfl ow duct connector or fi eld 
supplied connector to attach furnace to 
overhead supply duct. (see Figure 17)
7. Install return air grille in closet preferably
at same level as upfl ow stand or below 
mounting platform (see Figure 18).
NOTE: Be certain to provide an adequate free 
return air area as described under Return Air 
Codes and Requirements and Closed-Off Space 
Requirements.
Through-the-Floor Return Air System 
(Ducted)
1. Prepare Floor Opening(s):
a. Mark fl oor opening(s) as shown in Figure
19. Provide minimum clearances at rear 
and left side walls of closet for installation 
of furnace and wiring.
b. Cut fl oor opening on outside edge of
marked line so that opening is slightly 
larger than area marked.
c. Additional provisions may be necessary
for optional air conditioning if refrigerant 
lines are installed other than at the front 
of the furnace.
2. If return air duct is made of combustible
material, locate a pan fabricated of non-
combustible material with 1” upturned 
fl anges under furnace return air opening. 
Figure 18. Over-the-Floor Return Air
System
Coil Cabinet
Air Filter
Braced
Mounting
Platform
Front
Grille
Non-combustible
Pan or
Enclosure
WALL
FLOOR
