Use And Care Manual
8
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
All wiring must conform to local codes or 
latest edition of National Electrical Code 
ANSI/NFPA 70.
The voltage requirements and wattage load 
for the water heater are specified on the 
rating plate on the front of the water heater.
2
1
/2 gallon models are supplied with a 
plug connected power supply cord for use 
only in 120 VAC applications. The cord 
must be connected to a properly grounded 
receptacle on a branch circuit with copper 
conductors, an over current protection 
device and a suitable disconnect means. 
If desired, straight field wiring connections 
can be made to these models by removing 
the access cover on front of heater and 
disconnecting the cord set from the 
thermostat and the grounding plug. Remove 
the cord set and strain relief bushing 
from the junction bracket. The hole in the 
junction bracket will accommodate 1/2″ 
or 3/4″ electrical fittings. Refer to wiring 
diagrams in the back of this manual for 
wiring connections.
6 through 30 gallon models are completely 
wired to the junction bracket inside jacket 
at front of water heater. An opening for 
1/2″ or 3/4″ electrical fitting is provided 
for field wiring connections. A separate 
branch circuit with copper conductors, 
overcurrent protective device and suitable 
disconnecting means must be provided 
by a qualified electrician. Refer to wiring 
diagrams in the back of this manual for 
wiring connections.
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.
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
  Total Water  Recommended Over Current Protection    Copper Wire Size AWG Based  
  Heater Wattage  (fuse or circuit breaker amperage rating)    on N.E.C. Table 310-16 (75°C.)
     120V 208V 240V  120V 208V 240V
  1500*   20 15 15  12 14 14
  1700   20 15 15  12 14 14
  2000   25 15 15  10 14 14
  2500   30 15 15  10 14 14
  3000   35 20 20  8 12 12
    3500    –  25  20    –  10  12
   3800    –  25  20    –  10  12
   4000    –  25  25    –  10  10
   4500    –  30  25    –  10  10
   5000    –  30  30    –  10  10
   5500    –  35  30    –  8  10
   6000    –  40  35    –  8  8
   9000    –  –  50    –  –  8
* Less than 1500 watts may be wired 14 gauge with 15 amp protection. Check Local Electrical Codes, as they will also apply.
Condensation
Condensation can form on the tank when 
it is first filled with water. Condensation 
might also occur with a heavy water draw 
and very cold inlet water temperature.
This condition is not unusual, and will 
disappear after the water becomes heated.  
If, however, the condensation continues, 
examine the piping and fittings for 
possible leaks.
Additional information on this subject 
may be found at www.rheem.com under 
“Library”. Scroll down to the Technical 
Service Bulletins 1300 Series Section and 
choose Bulletin #1303.










