User Guide

8
Installing the water heater.
NOTICE: This guide recommends minimum branch circuit sizing and wire size based on National Electric Code. Refer to
wiring diagrams in this manual for field wiring connections.
Branch Circuit Sizing and Wire Size Guide
CAUTION: The presence
of water in the piping
and water heater does
not provide sufficient
conduction for a ground.
Non-metallic piping,
dielectric unions, flexible
connectors etc. can cause
the water heater to be
electrically isolated.
Electrical Connections
A separate branch circuit with copper
conductors, overcurrent protective device
and suitable disconnecting means must be
provided by a qualified electrician.
All wiring must conform to local codes or
latest edition of National Electrical Code
ANSI/NFPA 70.
The water heater is completely wired to
the junction box inside jacket at the top
front of the water heater. An opening for
1/2″ or 3/4″ electrical fitting is provided
for field wiring connections.
The voltage requirements and wattage
load for the water heater are specified
on the rating plate on the front of the
water heater.
The branch circuit wiring should include
either:
Metallic conduit or metallic sheathed
cable approved for use as a
grounding conductor and installed
with fittings approved for the
purpose.
Non-metallic sheathed cable,
metallic conduit or metallic sheathed
cable not approved for use as a
ground conductor shall include a
separate conductor for grounding. It
should be attached to the ground
terminals of the water heater and the
electrical distribution box.
WARNING
WARNING
Water heater junction box.
Junction
box cover
Wire connections
Ground screw
Conduit
connector
Single Phase
Wiring
3 Phase
Wiring
!
Total Water
Heater Wattage
Recommended Over Current Protection
(Fuse or circuit breaker amperage rating)
Copper Wire Size AWG Based on
NE.C. Table 310-16 (75°C)
120V 208V 240V 277V 480V 120V 208V 240V 277V 480V
1,500 20 15 15 15 15 12 14 14 14 14
2,000 25 15 15 15 15 10 14 14 14 14
3,000 35 20 20 15 15 8 12 12 14 14
4,000 - 25 25 20 15 - 10 10 12 14
4,500 - 30 25 25 15 - 10 10 10 14
5,000 - 30 30 25 15 - 10 10 10 14
5,500 - 35 30 25 15 - 8 10 10 14
6,000 - 40 35 30 20 - 8 8 10 12
8,000 - 50 45 40 25 - 8 8 8 10
9,000 - - 50 45 25 - - 8 8 10
10,000 - - - 50 30 - - - 8 10
11,000 - - - 50 30 - - - 8 10
12,000 - - - - 35 - - - - 8
Total Water
Heater Wattage
Recommended Over Current Protection
(Fuse or circuit breaker amperage rating)
Copper Wire Size AWG Based on NE.C.
Table 310-16 (75°C)
208V 240V 277V 480V 208V 240V 277V 480V
3,000 20 20 15 15 12 12 14 14
4,000 25 25 20 15 10 10 12 14
4,500 30 25 25 15 10 10 10 14
5,000 30 30 25 15 10 10 10 14
5,500 35 30 25 15 8 10 10 14
6,000 40 35 30 20 8 8 10 12
8,000 50 45 40 25 8 8 8 10
9,000 - 50 45 25 - 8 8 10
10,000 - - 50 30 - - 8 10
11,000 - - 50 30 - - 8 10
12,000 - - - 35 - - - 8