PURGING OF GAS LINE
Gas line purging is required with new piping or systems in which air has entered.
CAUTION
PURGING SHOULD BE PERFORMED BY PERSONS EXPERIENCED IN THIS TYPE OF GAS SERVICE TO AVOID RISK OF FIRE OR EXPLOSION. PURGE DISCHARGE MUST NOT ENTER CONFINED AREAS OR SPACES WHERE IGNITION CAN OCCUR. THE AREA MUST BE WELL VENTILATED AND ALL SOURCES OF IGNITION MUST BE DEACTIVATED OR REMOVED.
BEFORE PLACING THE BOILER IN OPERATION, CHECK FOR GAS LEAKAGE. USE A SOAP AND WATER SOLUTION OR OTHER MATERIALACCEPTABLE FOR THE PURPOSE OF LOCATING GAS LEAKS. DO NOT USE MATCHES, CANDLES, FLAME OR OTHER SOURCES OF IGNITION FOR THIS PURPOSE.
WARNING
THE GAS VALVE MUST HAVE BEEN IN THE OFF POSITION FOR AT LEAST 5 MINUTES. This waiting period is an important safety step. Its purpose is to permit gas that may have accumulated in the combustion chamber to clear. IF YOU DETECT GAS ODOR AT THE END OF THIS PERIOD DO NOT PROCEED WITH LIGHTING. RECOGNIZE THAT GAS EVEN IF IT SEEMS WEAK, MAY INDICATE PRESENCE OF ACCUMULATED GAS SOMEPLACE IN THE AREA WITH RISK OF FIRE OR EXPLOSION. SEE THE FRONT PAGE FOR STEPS TO BE TAKEN.
INLET GAS PRESSURE
The inlet gas pressure is measured by removing the low gas pressure switch located on the main gas manifold which is upstream of the unit's combination gas valves. The maximum value specified in the table must not be exceeded. The minimum values shown in table 17 must be maintained under both load and no load conditions (static and dynamic). The combination gas valves supplied with the boiler are for low pressure service. If upstream pressure exceeds 14.0" W.C., an intermediate gas pressure regulator of the lockup type must be installed.
TABLE 17.
Inlet Gas Pressure | Nat. Gas | Prop. Gas |
Max. Inlet Pressure (Inches W.C.) | 14.0 | 14.0 |
Min. Inlet Pressure (Inches W.C.) | 6.0 | 11.0 |
MANIFOLD PRESSURE
The manifold gas pressure is measured at the pressure tap on the downstream side of the combination gas valve(s). For natural gas the Manifold Pressure should measure 3.5" W.C. For propane (LP) gas, the pressure should read 10" W.C.
IMPORTANT
UNDER NO CIRCUMSTANCES SHALL THE GAS PRESSURE MEASURED AT THE BURNER MANIFOLD EXCEED THAT STATED ON THE BOILER RATING PLATE. OVERFIRING WILL RESULT IN DAMAGE TO THE BOILER, AS WELL AS INCREASED RISK OF FIRE, SOOTING AND ASPHYXIATION.
ADJUSTMENTS
ON INITIAL STARTUP SOME ADJUSTMENTS ARE NECESSARY. 1. CHECK MANIFOLD AND INLET GAS PRESSURES.
2.CHECK THE INPUT. SEE SECTIONS "INLET GAS PRESSURE:" AND SEE NATIONAL FUEL GAS CODE, ANSI Z223.1 OR CAN/ CSA - B149.1 AND .2 (AND LATEST ADDENDA) FOR PROCEDURES.
DANGER
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.
THE WATER HEATER SHOULD BE LOCATED IN AN AREA WHERE THE GENERAL PUBLIC DOES NOT HAVE ACCESS TO SET TEMPERATURES.
It is recommended in domestic hot water applications that lower water temperatures be used to avoid the risk of scalding. It is further recommended, in all cases, that the water temperature be set for the lowest temperature which satisfies the user's hot water needs. This will also provide the most energy efficient operation of the boiler and minimize scale formation in the heat exchanger, thus prolonging the life of the boiler.
SETTING THE WATER HEATER TEMPERATURE AT 120°F (49°C) WILL REDUCE THE RISK OF SCALDS. Some states require settings at specific lower temperatures. Table 18 below shows the approximate
TABLE 18. Risk of Scalds
Temperature | Time to Produce 2nd & 3rd |
Setting | Degree Burns on Adult Skin |
Over 170°F (77°C) | Nearly instantaneous |
160°F (71°C) | About 1/2 second |
150°F (66°C) | About |
140°F (60°C) | Less than 5 seconds |
130°F (54°C) | About 30 seconds |
120°F (49°C) or less | More than 5 minutes |
USE
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