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The boiler should be located in an area that is inaccessible to the
general public.
Never allow small children to use a hot water tap or to draw their
own bath water. Never leave a child or handicapped person unat-
tended in a bathtub or shower.
TABLE 9. Risk of Scalds.
Water Temperature
Time to Produce 2nd & 3rd
Degree Burns on Adult Skin
180°F (82°C)
Nearly instantaneous
170°F (77°C)
Nearly instantaneous
160°F (71°C)
About 1/2 second
150°F (66°C)
About 1-1/2 seconds
140°F (60°C)
Less than 5 seconds
130°F (54°C)
About 30 seconds
120°F (49°C)
More than 5 minutes
SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL
TO SHUT OFF, TURN OFF THE MAIN MANUAL GAS SHUTOFF
VALVE TO THE APPLIANCE.
The operating temperature of boiler must be maintained as follows:
• 120°F (49°C) or higher inlet water temperature to the boiler.
• 20°F (11°C) differential between boiler’s inlet and outlet (e.g. 120°F
[49°C] inlet, 140°F [60°C] outlet minimum design temperatures).
If the inlet water temperature into boiler is less than 120°F (49°C),
adjustments on the water bypass and outlet valves at the rear
of boiler are required. See Figures 14 and 15. Wait at least
one minute between adjustments for the temperature to stabilize.
1) If necessary, throttle down (close) the water outlet gate/ball
valve until the desired outlet water temperature (120°F [49°C]
minimum) is reached. Wait one minute.
2) Note the outlet and inlet temperature indicator readings.
a) If the inlet water temperature is less than 120°F (49°C),
open, in small increments, the bypass (balancing) valve
until the minimum 120°F (49°C) inlet water temperature
or 20°F (11°C) differential, whichever has the higher inlet
temperature, is attained.
b) If the inlet water temperature is greater than 120°F (49°C)
and the 20°F (11°C) differential is not present, close the
bypass valve until the 20°F (11°C) differential is attained.
NOTE: It may be necessary to make further adjustments on
the
outlet and bypass valves until the desired inlet and outlet
water temperatures are reached.
MANIFOLD PRESSURE CONNECTIONS
Take the manifold pressure, refer to Table 1, by removing the pipe
plug and inserting a suitable 1/8” NPT hose barb for connection to
the manometer/pressure gauge. Upon completion of measurements
and adjustments, remove the hose barb and replace the pipe
plug. Check for gas leaks and insure all connections are gas tight,
see Figure 18.
WATER TEMPERATURE REGULATION
HOT WATER CAN SCALD: Boilers are intended to produce hot
water. Water heated to a temperature which will satisfy space
heating, clothes washing, dish washing and other sanitizing
needs can scald and permanently injure you upon contact.
Some people are more likely to be permanently injured by hot
water than others. These include the elderly, children, the infirm
or physically/mentally disabled. If anyone using hot water in your
home fits into one of theses groups or if there is a local code or
state law requiring a specific temperature water at the hot water
tap, then you must take special precautions. In addition to using
the lowest possible temperature setting that satisfies your hot
water needs, a means such as a mixing valve should be used
at the hot water taps used by these people or at the hot water
supply tank. Mixing valves are available at plumbing supply
or hardware stores. Follow the manufacturer’s instructions for
installation of the valves. Before changing the thermostat setting
on the hot water system controller, see Table 9.
Hot water temperatures required for automatic dishwasher
and laundry use can cause scald burns resulting in serious
personal injury and/or death. The temperature at which injury
occurs varies with the person’s age and time of exposure. The
slower response time of children, aged or disabled persons
increases the hazards to them. Never allow small children to
use a hot water tap, or to draw their own bath water. Never
leave a child or disabled person unattended in a bathtub
or shower.