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SECTION II: GENERAL INFORMATION (cont .)
TEMPERATURE CONTROL (cont.)
ANODE RODS
The anode rod is used as a sacrificial element within the volume of the storage tank. The purpose
of the magnesium anode rod is to protect the inside of the tank against corrosion. Anode rods
should be inspected twice in the first year and at least yearly once a time interval for inspection
has been developed. Water conditions can influence the consumption rate of the anode rods.
Please see the Maintenance section of this manual for instructions on how to change the anode
rods.
CAUTION
Hydrogen gas is produced in a hot water system served by the heater that has not been
used for a long period of time (2 weeks or more). Hydrogen gas is extremely flammable.
To reduce the risk of injury under these conditions, it is recommended that the hot water
faucet be opened for several minutes at the kitchen sink before using any electrical
appliance connected to the hot water system. When hydrogen is present, there will
probably be an unusual sound such as air escaping through the pipe as the water begins
to flow. There should be no smoking or open flame near the faucet at the time it is open.
TEMPERATURE AND PRESSURE RELIEF VALVE (T&P)
CAUTION
To reduce the risk of excessive pressures and temperatures in this water heater, install
temperature and pressure protective equipment required by local codes and no less
than a combination temperature and pressure relief valve certified by a nationally
recognized testing laboratory that maintains periodic inspection of production of listed
equipment or materials, as meeting the requirements for Relief Valves and Automatic
Gas Shutoff Devices for Hot Water Supply Systems, ANSI Z21.22. This valve must be
marked with a maximum set pressure not to exceed the marked maximum working
pressure of the water heater. Install the valve in an opening provided and marked for
this purpose in the water heater, and orient it or provide tubing so that any discharge
from the valve exits only within 6 inches above, or at any distance below, the structural
floor, and does not contact any live electrical part. The discharge opening must not be
blocked or reduced in size under any circumstances.
APPROXIMATE
TEMPERATURE/TIME
RELATIONSHIPS TO
SCALDING
120°F (49°C) More than 5 minutes
125°F (52°C) 1
1
⁄
2
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 1
1
⁄
2
seconds
155°F (68°C) About 1 second
Table 2: Scald Temperature/Time Relationships
