100324051_2000579115 _Rev. 01
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Water
Temperature
°F
Time for 1st
Degree Burns
(Less Severe Burns)
Time for Permanent
Burns 2nd & 3rd
Degree (Most
Severe Burns)
110
(normal shower temp.)
116
(pain threshold)
116
35 minutes
45 minutes
122
1 minute
5 minutes
131
5 seconds
25 seconds
140
2 seconds
5 seconds
149
1 second
2 seconds
154
instantaneous
1 seconds
(U.S. Government Memorandum, C.P.S.C., Peter L.
Armstrong, Sept. 15,1978)
Table 1.
In addition to using lowest possible temperature setting
that satisfies demand of application, to reduce the risk of
scalding, install Thermostatic Mixing Valves (temperature
limiting valves) (see Figure 6) at each point-of-use. These
valves automatically mix hot and cold water to limit the
temperature at the tap.
Thermostatic Mixing Valves are available from your
local plumbing supplier. Consult a Qualified Installer or
Service Agency. Follow mixing valve manufacturer’s
instructions for installation of the valves. Before
changing the factory setting on the thermostat, read the
"Operating The Temperature Control System" section in
this manual.
WATER HEATER OPERATION
Figure 7 shows the water heater’s sequence of operation
when a call for heat is initiated. The ignition control module
will attempt to light the burner three times. If the ignition
control does not detect ignition it will enter lockout mode
and flash the corresponding error code.
HEATER CONTROL
CHECKS TO ENSURE
BLOWER EXHAUST
PRESSURE SWITCH IS
OPEN
BLOWER IS ENERGIZED
CONTROL CHECKS TO
ENSURE: EXHAUST
PRESSURE SWITCH
CLOSES AND INTAKE
PRESSURE SWITCH
REMAINS CLOSED
INDICATING BLOWER IS
OPERATING AND THERE
ARE NO BLOCKAGES
(INTAKE OR EXHAUST)
TEMPERATURE SWITCH
REMAINS CLOSED
INDICATING VENT
TEMPERATURE IS NOT
ABOVE THE ALLOWABLE
LIMIT
IGNITER IS ENERGIZED
AND GAS VALVE IS
OPENED
BURNER COMES ON AND
THE FLAME IS SENSED
BY CONTROL
BURNER CONTINUES
TILL THE WATER IN
THE TANK REACHES
THERMOSTAT SETTING
GAS VALVE IS CLOSED
AND BURNER SHUTS
OFF
HEATER
THERMOSTAT
CALLS FOR
HEAT
HEATER
REMAINS ON
STANDBY UNTIL
NEXT CALL FOR
HEAT
BLOWER CONTINUES
FOR A POST PURGE
TIME
Figure 7.
