Service Manual
VII - GAS PRESSURE SETTING PROCEDURE
All settings/adjustments must be performed
by a qualified Service Technician.
1. Turn unit off at power source and turn off the gas to the water heater.
2. Remove the front cover from the water heater.
3. Remove the gas pressure test port plug. Connect manometer to this port. (See Figure #1 for
location of the test port plug.) Turn on the gas and power to the water heater.
4. Flow water through the water heater at the maximum flow rate obtainable.
5. To adjust the “
Low” fire pressure, use small (pocket) common screwdriver to set combustion
control dip switch #1 to the “OFF” position, switch # 7 to the “ON” position, and switch #8 to
the “
OFF” position (see figure #2 for location of combustion control switches.) This will put the
unit into forced low fire. Check the pressure reading on your manometer. If the pressure needs
adjusting, remove the rubber plug from the bottom of the water heater casing (located beneath
the regulator), to access the regulator adjustment screw. Adjust the pressure to the correct
setting (See figure #1 for location of the regulator adjustment screw.) Below are the proper
pressures for “
Low” fire, per gas type being used.
Propane 0.93” w.c. @ 11” w.c. supply (Low fire rate of 15,000 BTU’s)
Natural 0.77” w.c. @ 7” w.c. supply (Low fire rate of 15,000 BTU’s)
6. To adjust the “High” fire pressure, use small (pocket) common screwdriver to set combustion
control dip switch #1 to the “
ON” position, switch # 7 to the “ON” position, and switch #8 to
the “
ON” position (see figure #2 for location of the combustion control switches), this will put
the unit into forced high fire. Check the pressure reading on your manometer. If the pressure
needs adjusting, use small (pocket) common screwdriver to adjust the high pressure “Pot”.
(See figure #2 for location of “
high pressure setting pot”.)
Below are the proper pressures for “High” fire, per gas type being used.
Propane 4.2” w.c. @ 11” w.c. supply (High fire rate of 180,000 BTU’s)
Natural
3.7” w.c. @ 7” w.c. supply (High fire rate of 180,000 BTU’s)
7. Verify both low and high fire pressures by placing the water heater into “Forced Low Fire” and
“Forced High Fire” as described in steps 5 and 6 above. This completes the gas pressure
setting procedure.
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