6 | FCC rules
WARNING: Personal Injury from toxic chemicals.
▶ A water heater which will be used to supply potable
water shall not be connected to any heating system
or component(s) previously used with a nonpotable
water heating appliance.
WARNING: Installation in mobile homes.
▶ Installation in mobile homes shall conform to Title 24
CFR, part 3280 and/or CAN/CSA Z240 MH Series,
FCC: This device complies with Part 15 of the FCC rules. Operation is
subject to the following two conditions: (1) This device may not cause
harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation.
The chart below shows the relationship between water temperature and
time until there is a risk of scalding. It can be used as the basis for
determining the safest water temperature for your application.
6 720 644 956 (2016/05)
120 °F (48 °C)
125 °F (51 °C)
130 °F (54 °C)
135 °F (57 °C)
140 °F (60 °C)
145 °F (62 °C)
150 °F (65 °C)
155 °F (68 °C)
Table 2 Approximate time-temperature relationship until there is a risk
1) Source: Moritz, A.R. and Henriques, F.C., Jr. (1947). Studies of thermal injury.
II. The relative importance of time and surface temperature in the causation of
cutaneous burns, Am J of Pathol, 23, 695-720.
Time to severe scalding
longer than 5 minutes
1.5 to 2 minutes
approx. 30 seconds
approx. 10 seconds
less than 5 seconds
less than 3 seconds
approx. 1.5 seconds
approx. 1 second