John Wood Direct Vent - Manuel (Page 27)

www. johnwoodwaterheaters .com 27
TEMPERATURE REGULATION
TEMPERATURE REGULATION
Temperature Adjustment
Valves for reducing the point-of-use temperature by mixing
cold and hot water are available (see Figure 8). Also
available are inexpensive devices that attach to faucets to
limit hot water temperatures. Contact a licensed plumber
or the local plumbing authority.
Note: During low demand periods, a lower thermostat
setting will reduce energy losses and may satisfy your
normal hot water needs. If hot water use is expected to
be more than normal, a higher thermostat setting may be
required to meet the increased demand. When leaving
your home for extended periods (e.g., vacations etc.) turn
the temperature dial to its lowest setting. This will maintain
the water at low temperatures with minimum energy losses
and prevent the tank from freezing during cold weather.
GAS CONTROL VALVE/THERMOSTAT
SETTINGS
GAS CONTROL/
TEMPERATURE KNOB
STATUS
LIGHT
IGNITER
68°C
(155°F)
MARK
65°C
(150°F)
MARK
60°C
(140°F)
MARK
55°C
(130°F)
MARK
49°C
(120°F)
MARK
33°C
(91°F)
MARK
Figure 30
The thermostat is adjusted to the “OFF” position when
it is shipped from the factory. Water temperature can be
regulated by moving the temperature dial to the preferred
setting. The preferred starting point is 49°C (120°F) at
the “HOT” setting. Align the knob with the desired water
temperature as shown in Figure 30. There is a hot water
scald potential if the thermostat is set too high.
Note: Temperatures shown on the gas control valve/
thermostat are approximates. The actual temperature of
the heated water may vary.
Important: Adjusting the thermostat past the 49°C (120°F)
mark on the temperature dial will increase the risk of scald
injury. Hot water can produce fi rst degree burns within:
Water
Temperature
°C (°F)
Time for 1st
Degree Burns
(Less Severe Burns)
Time for Permanent
Burns 2nd & 3rd
Degree (Most
Severe Burns)
44 (110) (normal shower temp.)
47 (116) (pain threshold)
47 (116) 35 minutes 45 minutes
50 (122) 1 minute 5 minutes
55 (131) 5 seconds 25 seconds
60 (140) 2 seconds 5 seconds
65 (149) 1 second 2 seconds
68 (154) instantaneous 1 seconds
(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong,
Sept. 15,1978)
Table 2
Should overheating occur or the gas supply fail to shut off,
turn “OFF” the manual gas shut-off valve to the appliance
(see Figure 1, item 18).
OPERATING THE TEMPERATURE CONTROL
SYSTEM
Water Temperature Adjustment
The water temperature setting can be adjusted from
33°C (91°F) to 68°C (155°F). Turn the Gas Control Valve/
Temperature Knob to the desired setting/temperature.
Note: The temperatures indicated are approximates. The
actual temperature of the heated water may vary.
Operating Modes And Settings
Standard Mode - The controller adjusts the water heater
to maintain the temperature set by the user.
Setting for vacation - The “LOW” position sets the
controller at approximately 33°C (91°F). This setting is
recommended for times when the water heater will not be
in use for an extended period of time. It effectively turns
the controller temperature setting down to a temperature
that prevents the water in the water heater from freezing
while still conserving energy.