A.O. Smith Power Vent Gas Series, Installation And Operating Manual

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Water
Temperature
Time for 1st
Degree Burn
(Less Severe
Burns)
Time for
Permanent Burns
2nd & 3rd Degree
(Most Severe
Burns)
110°F (44°C) (normal shower
temp.)
116°F (47°C) (pain threshold)
116°F (47°C) 35 minutes 45 minutes
122°F (50°C) 1 minute 5 minutes
131°F (55°C) 5 seconds 25 seconds
140°F (60°C) 2 seconds 5 seconds
149°F (65°C) 1 second 2 seconds
154°F (68°C) instantaneous 1 second
(U.S. Government Memorandum, C.P.S.C., Peter L.
Armstrong, Sept. 15,1978)
TABLE 3
Setting Desired Temperatures
1. Set the key lock to the “Off” position
2. Select the desired mode button (vacation, energy saver
or boost)
3. U s i n g t h e a r r o w b u t t o n s s e l e c t t h e d e s i r e d
temperature
Key Lock
NOTE: This is a tamper resistant feature.
The Key Lock is considered “On” or “Off”:
• Key Lock is turned “On” one minute after the unit has
been plugged in.
• Key Lock can then be turned “Off” for one minute
by simultaneously pressing the “Up” Button and the
“Down” Button for three seconds.
When the keys are locked, the Temperature Set-point
cannot be increased or decreased, and the Operating
Mode cannot be changed.
The On/Off Button is not affected by the Key Lock feature.
All other buttons are “locked” when the Key Lock is
“On”.
A lock or unlock LED icon will display the condition. The
Icon will be composed of 3 components, the base, a locked
and an unlocked arc.
Operating Mode Selection
Operation modes are: Boost (peak demand), Energy Saver
and Vacation.
Initial conditions after starting-up the control is determined
by evaluation of the stored set-point.
Vacation Mode is selected if the Temperature Set-point
value is less than 100°F (38°C). Boost Mode is selected if
the Temperature Set-point value is greater than or equal to
140°F (60°C). Energy Saver Mode is selected for all other
Temperature set-point values.
Three LED’s are used to indicate the Operating Mode
Selection
Vacation Mode:
Yellow LED
Energy Saver Mode: Green LED
Boost Mode:
Orange LED
The Operating Modes have the following characteristics:
Vacation mode:
• Fixed temperature setting of 90°F (32°C)
Energy Saver mode:
• Temperature range from 100°F to 135°F (38°C to 57°C)
in increments of 1°F or 1°C
Boost mode:
• Temperature range from 140°F to 158°F (60°C to 70°C)
in increments of 1°F or 1°C
Switching between operation modes is done by pressing
the “Mode” Button when the Key Lock is “Off”. When
a mode is active, the corresponding LED is turned on.
Pressing the “Mode” button will cycle between the three
possible modes of operation.
Each time the “Mode” Button is changed by the user,
the controller display is to respond with the following
actions:
1. The Temperature Set-point changes to the lowest
temperature for the respective mode (e.g. 100°F (38°C)
for “Energy Saver” and 140°F (60°C) for “Boost” mode)
and is communicated to the master device.
2. The LED corresponding to the new mode is turned
on.
UNIQUE HYBRID FEATURES
Temperature Measurement
Temperature Probes
The water heater has support for three independent
temperature probes:
1. Water Inlet Temperature Probe
The water inlet temperature probe contains a
thermistor and measures the temperature of the
water entering the heat engine enclosure.
2. Water Outlet Temperature Probe
The water outlet temperature probe contains a
thermistor and measures the temperature of the
water leaving the heat engine enclosure. This supply
of (hot) water is delivered to the top of the storage
tank in close proximity to the outlet fi tting.
3. Tank Temperature Probe
The tank probe contains a thermistor and measures
the temperature of the water in the storage tank at
a specifi c location between the top and the bottom
of the tank.