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required by these appliances, you might create the potential for scald injury. To protect against injury, you must install the ASSE
approved mixing valve supplied with the water heater in the water system. This valve will reduce point of discharge temperature by
mixing cold and hot water in branch supply lines. Follow the instructions supplied with the mixing valve for proper installation and
adjustment. The following chart details the relationship of water temperature and time with regard to scald injury and may be used
as a guide in determining the safest water temperature for your applications.
Approximate Time/Temperature Scald Chart
APPROXIMATE TIME/TEMPERATURE
RELATIONSHIPS IN SCALDS
120°F (49°C) More than 5 minutes
125°F (52°C) 1½ to 2 minutes
130°F (54°C) About 30 seconds
135°F (57°C) About 10 seconds
140°F (60°C) Less than 5 seconds
145°F (63°C) Less than 3 seconds
150°F (66°C) About 1½ seconds
155°F (68°C) About 1 second
Table 2.
ALTERNATE SPACE HEATING WATER CONNECTIONS
DANGER
Toxic chemicals, such as those used for boiler treatment, must not be introduced into potable water used for space heating.
This water heater must not be connected to an existing heating system or component(s) previously used with a non-potable
water heating appliance.
All piping components connected to this water heater for space heating applications must be suitable for use with potable
water.
WARNING
When the system requires water for space heating at temperatures higher than required for other means, the supplied ASSE
approved mixing valve must be installed to temper the water for those uses in order to reduce the scald hazard potential.
Failure to properly pipe this water heater may result in improper operation and damage to the water heater or structure.
Oxygen contamination of this water heater will cause corrosion of iron and steel components, and can lead to water heater
failure.
Connect the system supply and return piping to the water heater.
Refer to Figure 10 and Figure 11 for installation examples. Maintain
a minimum ½ inch (1.3 cm) clearance from hot water piping to
combustible materials.
Figure 10. Alternate Space Heating Connections
M
ain Powe
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