11
Water heated to a temperature which will satisfy clothes washing,
dish washing, and other sanitizing needs can scald and cause
permanent injury upon contact. Short repeated heating cycles
caused by small hot water uses can cause temperatures at the
point of use to exceed the water heater’s temperature setting by
up to 20°F (11°C).
Some people are more likely to be permanently injured by
hot water than others. These include the elderly, children, the
in
fi
rm and the physically/mentally disabled. Table 6 shows the
approximate time-to-burn relationship for normal adult skin.
If anyone using hot water provided by the water heater being
installed
fi
ts into one of these groups or if there is a local code
or state law requiring a certain water temperature at the point of
use, then special precautions must be taken.
In addition to using the lowest possible temperature setting that
satis
fi
es the demand of the application a Mixing Valve should be
installed at the water heater (see Figure 10) or at the hot water
taps to further reduce system water temperature.
Mixing valves are available at plumbing supply stores. Consult
a Quali
fi
ed Installer or Service Agency. Follow mixing valve
manufacturer’s instructions for installation of the valves.
TABLE 6
Water Temperature
Time to Produce 2nd & 3rd
Degree Burns on Adult Skin
180°F (82°C)
Nearly instantaneous
170°F (77°C)
Nearly instantaneous
160°F (71°C)
About 1/2 second
150°F (66°C)
About 1-1/2 seconds
140°F (60°C)
Less than 5 seconds
130°F (54°C)
About 30 seconds
120°F (49°C)
More than 5 minutes
CIRCULATING PUMP WIRING DIAGRAM
DISHWASHER LOOP WITH TOGGLE SWITCH
FIELD SUPPLIED TEMPERATURE
CONTROL INSTALLED IN THE
CIRCULATING LOOP RETURN LINE
DISHWASHER
TOGGLE
SWITCH
CIRC
PUMP
MOTOR
L1 HOT
L2 NEUTRAL
120 VAC
POWER
NOTE:
USE SEPARATE 120 VAC POWER
SUPPLY FOR PUMP CIRCUIT. DO NOT
SHARE POWER WITH APPLIANCE AS THIS
MAY CAUSE ELECTRICAL LINE NOISE AND
LEAD TO ERRATIC CONTROL SYSTEM
OPERATION.
FIGURE 9
Some circulating pumps are manufactured with sealed bearings
and do not require further lubrication. Some circulating pumps
must be periodically oiled. Refer to the pump manufacturer’s
instructions for lubrication requirements.
CIRCULATING PUMP WIRING DIAGRAM
STORAGE TANK OR BUILDING RECIRCULATION
FIELD SUPPLIED TEMPERATURE CONTROL
INSTALLED IN THE STORAGE TANK
OR CIRCULATING LOOP RETURN LINE
CIRC
PUMP
MOTOR
L1 HOT
L2 NEUTRAL
120 VAC
POWER
NOTE:
USE SEPARATE 120 VAC POWER
SUPPLY FOR PUMP CIRCUIT. DO NOT
SHARE POWER WITH APPLIANCE AS THIS
MAY CAUSE ELECTRICAL LINE NOISE AND
LEAD TO ERRATIC CONTROL SYSTEM
OPERATION.
FIGURE 8
SUPPLY GAS REGULATOR
The water heater covered by this manual requires a supply gas
regulator to be installed in the supply gas line serving the water
heater for proper operation. Supply gas regulators are required
on high and low pressure gas supply systems.
NOTE:
On multiple water heater installations each water heater
shall have its own dedicated supply gas regulator installed in the
supply gas line serving the water heater.
Supply gas regulators must be rated at or above the input Btu/
hr rating of the water heater they supply. Supply gas regulators
shall have inlet and outlet connections not less than the minimum
supply gas line size for the water heater they serve as shown in
Table 5. The Maxitrol 325-7L or equivalent is recommended.
See Supply Gas Regulator Installation on page 11.
POWER SUPPLY
The water heaters covered in this manual require a 120 VAC,
1Ø (single phase), 60Hz, 15 amp power supply and must also
be electrically grounded in accordance with local codes or, in the
absence of local codes, with the National Electrical Code, ANSI/
NFPA 70 or the Canadian Electrical Code, CSA C22.1.
MIXING VALVES
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury.
Feel water before bathing or
showering.
Temperature limiting devices such as
mixing valves must be installed
when required by codes and to
ensure safe temperatures at fixtures.
INSTALLATION REQUIREMENTS
