State GS6 75 URRBS - Manual (Page 8)

8
fuel burning equipment. This practice is prohibited by many local
building codes as is the practice of venting gas fi red equipment to
the duct work of ventilation systems.
• Where a separate vent connection is not available and the vent
pipe from the heater must be connected to a common vent with an
oil burning furnace, the vent pipe should enter the smaller common
vent or chimney at a point above the large vent pipe.
FIGURE 3.
VENT CONNECTION
Vent connections must be made to an adequate stack or chimney. Size
and install proper size vent pipe. Do not reduce pipe size to less than
that of the blower outlet.
Horizontal runs of vent pipe must have a minimum upward slope
toward the chimney of 1/4 inch per foot (2cm per meter). Dampers or
other obstructions must not be installed in between the heater and the
blower. Be sure that the vent pipe does not extend beyond the inside
wall of the chimney.
Where a continuous or intermittent back draft is found to exist, the
cause must be determined and corrected. A special vent cap may be
required. If the back draft cannot be corrected by the normal methods or
if a suitable draft cannot be obtained, a blower type fl ue gas exhauster
must be employed to assure proper venting and correct combustion.
THERMOMETERS (Not Supplied)
Thermometers should be obtained and fi eld installed as shown in Figure 3.
Thermometers are installed in the system as a means of detecting the
temperature of the outlet water supply.
COMBINATION WATER (POTABLE) HEATING
AND SPACE HEATING
1. All piping components connected to this unit for space heating
applications shall be suitable for use with potable water.
2. These water heaters connot be used in space heating applications
only.
3. Toxic chemicals, such as those used for boiler treatment, shall
NEVER be introduced into this system.
4. This unit may NEVER be connected to any existing heating system
or component(s) previously used with a non-potable water heating
appliance.
5. When the system requires water for space heating at temperatures
higher than required for domestic water purposes, a tempering valve
must be installed. Please refer to installation diagram on page 6 of
this manual for suggested piping arrangements.
CAUTION
A closed system will exist if a check valve (without bypass), pressure
reducing valve (without bypass), or a water meter (without bypass) is
installed in the cold water line between the water heater and street
main (or well).
Excessive pressure may develop in such closed systems, causing
premature tank failure or intermittent relief valve operation. This is not a
warranty failure. An expansion tank or a similar device may be required
in the inlet supply line between the appliance and the meter or valve to
compensate for the thermal expansion of the water.
As water is heated, it expands (thermal expansion). In a closed system, the
volume of water will increase. As the volume of water increases, there will
be a corresponding increase in water pressure due to thermal expansion.
Thermal expansion can cause premature tank failure (leakage). This type
of failure is not covered under the limited warranty. Thermal expansion
can also cause intermittent temperature-pressure relief valve operation:
water discharged from the valve due to excessive pressure build up. The
temperature-pressure relief valve is not intended for the constant relief
of thermal expansion. This condition is not covered under the limited
warranty.
A properly-sized thermal expansion tank should be installed on all closed
systems to control the harmful effects of thermal expansion. Contact a
plumbing service agency or your retail supplier reguarding the installation
of a thermal expansion tank.
MIXING VALVES
DANGER
Water temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the physically
or mentally disabled are at highest risk
for scald injury.
Feel water before bathing or showering.
Temperature limiting devices such as
mixing valves must be installed when
required by codes and to ensure safe
temperatures at fixtures.
Water heated to a temperature which will satisfy clothes washing, dish
washing, and other sanitizing needs can scald and cause permanent
injury upon contact. Short repeated heating cycles caused by small hot
water uses can cause temperatures at the point of use to exceed the
water heater’s temperature setting by up to 20°F (11°C).
Some people are more likely to be permanently injured by hot water than
others. These include the elderly, children, the infi rm and the physically/
mentally disabled. Table 1 shows the approximate time-to-burn
relationship for normal adult skin. If anyone using hot water provided by
the water heater being installed fi ts into one of these groups or if there
is a local code or state law requiring a certain water temperature at the
point of use, then special precautions must be taken.
In addition to using lowest possible temperature setting that satisfi es demand of
application a Mixing Valve should be installed at water heater (see Figure 3)
or at hot water taps to further reduce system water temperature.
Mixing valves are available at plumbing supply stores. Consult a Qualifi ed
Installer or Service Agency. Follow mixing valve manufacturer’s instructions
for installation of the valves.