FIGURE 6-THERMOSTAT FOR NATURAL AND
PROPANE GASES
GAS PRESSURE REGULATOR
The gas pressure regulator is built into the gas valve and is equipped to operate on the gas specified on model and rating plate. The regulator is factory adjusted to deliver gas to burner at correct water column pressure allowing for a nominal pressure drop through the controls.
The minimum gas supply pressure for input adjustment must not be less than 5.0" W.C. (1.24 kPa) for natural gas and 11.0" W.C. (2.74 kPa) for propane gas.
Do not subject the combination gas valve to inlet gas pressures of more than 14.0" w.c. (3.48 kPa). A service regulator is necessary if higher gas pressures are encountered.
Gas pressure specified in Table 2, refer to flow pressure taken at pressure tap of automatic gas valve while heater is operating.
OPERATION
It is recommended that a qualified person perform the initial firing of the heater. At this time the user should not hesitate to ask the
individual any questions which he may have in regard to the operation and maintenance of the unit.
WARNING
DO NOT ATTEMPT TO OPERATE WATER HEATER WITH COLD WATER INLET VALVE CLOSED.
NEVER OPERATE THE HEATER WITHOUT FIRST BEING CERTAIN IT IS FILLED WITH WATER AND A TEMPERATURE AND PRESSURE RELIEF VALVE IS INSTALLED IN THE RELIEF VALVE OPENING OF THE HEATER. DO NOT ATTEMPT TO OPERATE HEATER WITH COLD WATER INLET VALVE CLOSED.
TO OPERATE THE WATER HEATER
1.Close the heater drain valve by turning handle clockwise 
.
2.Open a nearby hot water faucet to permit the air in the system to escape.
3.Fully open the cold water inlet pipe valve allowing the heater and piping to be filled.
4.Close the hot water faucet as water starts to flow.
5.The heater is ready to be operated.
A checklist is included in the SERVICE INFORMATION section of this manual. By using this checklist the user may be able to make minor operational adjustments and save himself unnecessary service calls. However, the user should not attempt repairs which are not listed in this section.
PURGING
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 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 INACTIVATED OR REMOVED.
TABLE 2.
MANIFOLD PRESSURE SETTING
Model | Type of |
|
|
| Manifold | |
Number | Gas | Input |
| Pressure | ||
Natural | 75,100 Btu/Hr |
| 22 kW | 4.0 in. W.C. | 1.0 kPa | |
|
|
|
|
|
|
|
Propane | 75,100 Btu/Hr |
| 22 kW | 10.0 in. W.C. | 2.5 kPa | |
|
|
|
|
|
|
|
Natural | 75,100 Btu/Hr |
| 22 kW | 4.0 in. W.C. | 1.0 kPa | |
|
|
|
|
|
|
|
Propane | 75,100 Btu/Hr |
| 22 kW | 10.0 in. W.C. | 2.5 kPa | |
|
|
|
|
|
|
|
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