State GS6 75 URRBS - Manual (Page 9)

9
TABLE 4. GAS SUPPLY LINE SIZES (IN INCHES)*
Water Temperature °F
Time for 1 st 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)
HOT WATER
OUTLET
TO TANK
INLET
CHECK
VALVE
MIXING
VALVE
COLD
WATER
INLET
TEMPERED WATER
OUTLET
12” TO 15”
(30-38 cm)
CHECK
VALVE
FIGURE 4 .
SYSTEM CONNECTIONS
The system installation must conform to these instructions and to the
local code authority having jurisdiction. Good practice requires that all
heavy piping be supported.
RELIEF VALVE
This water heater is equipped with a combination temperature-pressure
relief valve that complies with the standard for relief valves for hot water
supply systems Z21.22-CSA 4.4.
FOR SAFE OPERATION OF THE
WATER HEATER, THE RELIEF VALVE(S) MUST NOT BE REMOVED
OR PLUGGED.
ASME ratings cover pressure relief capacities. ANSI ratings cover release
rate with temperature actuation.
In addition to the water heater relief valve, each remote storage tank
which may be used in conjunction with this appliance shall also be
installed with a properly sized, rated and approved combination
temperature (ANSI) and pressure (ASME) relief valve(s). This valve
shall comply with the standard for relief valves for hot water supply
systems Z21.22-CSA 4.4.
WARNING
THE PURPOSE OF RELIEF VALVE IS TO AVOID EXCESSIVE PRESSURE
OR TEMPERATURE INTO THE STEAM RANGE, WHICH MAY CAUSE
SCALDING AT FIXTURES, TANK EXPLOSION, SYSTEM OR HEATER
DAMAGE. NO VALVE IS TO BE PLACED BETWEEN THE
RELIEF
VALVE AND TANK.
Your local code authority may have other specifi c relief valve requirements.
A DRAIN LINE MUST BE CONNECTED TO THE RELIEF VALVE TO
DIRECT DISCHARGE TO A SAFE LOCATION TO AVOID SCALDING OR
WATER DAMAGE. THIS LINE MUST NOT BE REDUCED FROM THE
SIZE OF THE VALVE OUTLET AND MUST NOT CONTAIN VALVES,
RESTRICTIONS NOR SHOULD IT BE LOCATED IN FREEZING AREAS.
DO NOT THREAD OR CAP THE END OF THIS LINE. RESTRICTED OR
BLOCKED DISCHARGE WILL DEFEAT THE PURPOSE OF THE VALVE
AND IS UNSAFE. DISCHARGE LINE SHALL BE INSTALLED TO ALLOW
COMPLETE DRAINAGE OF BOTH THE VALVE AND LINE.
See SERVICE INFORMATION section for procedure and precautions.
The type, size and location of the relief valves must be in accordance
with local codes. The location of the relief valve is shown in Figure 1.
The heater has a factory installed high temperature limit switch.
GAS PIPING
Contact your local gas service company to ensure that adequate gas service
is available and to review applicable installation codes for your area.
Size the main gas line in accordance with Table 4. The fi gures shown
are for straight lengths of pipe at 0.5" W.C. (.125 kPa) pressure drop,
which is considered normal for low pressure systems. Note: Fittings
such as elbows, tees and line regulators will add to the pipe pressure
drop. Also refer to the current edition of the National Fuel Gas Code.
WARNING
The minimum gas supply pressure for input adjustment is 6.0" W.C.(1.49
kPa) for natural gas.
THE HEATER IS NOT INTENDED FOR OPERATION AT HIGHER THAN
14" W.C. (3.49 kPa) SUPPLY PRESSURE. EXPOSURE TO HIGHER GAS
SUPPLY PRESSURE MAY CAUSE DAMAGE TO THE CONTROL WHICH
COULD RESULT IN FIRE OF EXPLOSION.
If overpressure has occurred
such as through improper testing of gas lines or emergency malfunction
of the supply system, the control must be checked for safe operation.
Make sure that the outside vents on the supply regulators and the safety
vent valves are protected against blockage. These are parts of the gas
supply system not the heater. Vent blockage may occur during ice storms.
IT IS IMPORTANT TO GUARD AGAINST GAS VALVE FOULING FROM
CONTAMINANTS IN THE GAS WAYS. SUCH FOULING MAY CAUSE
IMPROPER OPERATION, FIRE OR EXPLOSION.
IF COPPER SUPPLY LINES ARE USED THEY MUST BE INTERNALLY
TINNED AND CERTIFIED FOR GAS SERVICE. BEFORE ATTACHING THE
GAS LINE, BE SURE THAT ALL GAS PIPE IS CLEAN ON THE INSIDE.
TO TRAP ANY DIRT OR FOREIGN MATERIAL IN THE GAS SUPPLY
LINE, A SEDIMENT TRAP MUST BE INCORPORATED IN THE PIPING
(SEE FIG. 5). THE SEDIMENT TRAP MUST BE READILY ACCESSIBLE
AND NOT SUBJECT TO FREEZING CONDITIONS. INSTALL IN
ACCORDANCE WITH RECOMMENDATIONS OF SERVING GAS
SUPPLIERS. REFER TO THE CURRENT EDITION OF THE NATIONAL
FUEL GAS CODE.
To prevent damage, care must be taken not to apply too much torque
when attaching gas supply pipe to gas valve inlet.
Apply joint compounds (pipe dope) sparingly and only to the male threads
of pipe joints. Do not apply compounds to the fi rst two threads. Use
compounds resistant to the action of liquefi ed petroleum gases.