Rheem RTGH-C95XLP Use And Care Manual page 81

Maintenance Notice (cont.)
9
Replace the front cover panel.
10
Turn on the remote control.
Error Code 88 Clearing
When a tankless water heater has a certain number
of hours of combustion, error code "88" is shown
on the remote control. It is highly recommended to
perform water heater maintenance activities such as
flushing the heat exchanger and/or replacing the water
treatment filter (if applicable). After these maintenance
activities are made, follow the steps below in order to
clear error code "88".
1
Turn on the remote control.
2
Turn off the gas and water to the water heater by
closing the shut-off valves.
INSTALLATION INSTRUCTIONS
11
Turn on the gas and water to the water heater by
opening the shut off valves.
3
Press the DOWN adjustment button repeatedly until
the lowest setting temperature shows in the LED
display.
4
Press and hold the DOWN and UP adjustment
button for 5 to 10 seconds.
5
Turn on the gas and water to the water heater by
opening the shut off valves.
If error code "88" is still shown, repeat steps 1 through
5 above.
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