Rheem Integrity 20 Owner's Manual And Installation Instructions page 21

Minimum test point gas pressure
Refer to the rating label on the water heater for
the minimum test point gas pressure.
1. Open a hot tap slowly until the burners ignite.
2. Press and hold down the MIN button ("1L" is
shown on the LED display), and observe the
reading on the manometer.
3. Release the MIN button. If the manometer
reading observed in Step 2 agrees with the
rating label, no further adjustment is required.
4. To adjust, press and hold down the adjuster
button ("LH" is shown on LED display).
Note: The adjuster button must be held
down continuously through steps 4 to 6.
5. Press the MIN button and observe the
reading on the manometer.
Note: While the MIN button is pressed, the
gas pressure will at first increase then decrease, cycling between an upper gas
pressure limit (39 on LED display) and a lower gas pressure limit (01 on LED
display).
6. Release the MIN button when the reading on the manometer agrees with the
rating label.
7. Release the adjuster button.
Notes:
If the burners extinguish and/or an error code starts to flash on the display, release
the MIN and adjuster buttons, close the hot tap, clear the error code, turn on the
water heater and recommence the procedure from Step 1.
If the adjuster button is released before Step 6, clear any error code (if displayed)
and recommence the procedure from Step 1.
To clear an error code, refer to Error Code on page 15.
Maximum test point gas pressure
Refer to the rating label on the water heater for the maximum test point gas pressure.
Follow Steps 1 to 7 above, but open the hot tap fully and use the MAX button instead
of the MIN button (NOTE: In Step 2, "3H" or "4H" will be shown on the LED display,
depending on the model of the water heater).
After setting the minimum and maximum test point gas pressures, close the hot tap,
remove the manometer and refit and tighten the test point screw. Open a hot tap
again so the burners ignite, then test for gas leaks. Replace the front panel and refit
screws. Close the hot tap.
TO TURN OFF THE WATER HEATER
If it is necessary to turn off the water heater on completion of the installation, such as
on a building site or where the premises is vacant, then:
Close the gas and water isolation valves at the inlets to the water heater.
Switch off the electrical supply at the power outlet to the water heater.
Drain the water heater (refer to Draining the Water Heater on page 6).
Note: The frost protection system will be rendered inoperable if electrical power is not
available at the water heater. Damage caused by freezing due to the unavailability of
power at the water heater is not covered by warranty (refer to Warranty Exclusions on
page 28). If there is a risk of freezing, then it is necessary to drain the water heater
(refer to Draining the Water Heater on page 6).
COMMISSIONING
L.E.D. Display
Test Point
Orifice
Washer
Test Point
screw
21
Adjuster Button
Max Button
Min Button
Manometer