Noritz ecoTOUGH NRC71 OD Installation Manual page 16

1. Open the Front Cover.
2. Connect the blue connector***** marked "FLUSH" for flushing on the Circuit Board.
3. Then the code "CCC" is displayed on the
4. Turn on the circulating pump to circulate the flushing solution through the water heater
for 1 hour at a rate of 1.5 gallons per minute or more.
5. The code "C60" is displayed on the Data Display when the water heater detects the flow of the
fflushing solution.
When 1 minute passes, the code "C60" will change to "C59" on the Data Display.
Please check whether the reverse connection of the hose (H1) and (H3) if the display number will not change.
In that case, the flow rate of the flushing solution may be under 1.5 gallons per minute.
6. When 1 hour passes, the code "C00" is flashing on the Data Display.
Do not disconnect the blue connector marked "FLUSH" for flushing on the Circuit Board.
7. Turn off the circulating pump.
The flushing solution needs to be rinsed and cleaned out of the water heater.
Below is the way to rinse and clean the flushing solution.
1. Remove both drain hoses (H2 and H3) from the bucket. And then place the drain hose (H3)
into the sink or outside to drain.
2. Close the drain valve (V3) and then open the water inlet valve (V1).
Do not open the fresh water outlet valve (V2).
3. Clean the water heater with fresh water for 3 minutes or more.
(Needs to have enough time to clean the water heater.)
4. Close the drain valve (V4) and then remove the drain hose (H3)
from the drain valve (V4).
5. Remove the drain hose (H1) from the drain valve (V3).
6. Disconnect the blue connector marked "FLUSH" for flushing on the Circuit Board.
The code "C00" goes out on the Data Display.
7. Close the Front Cover.
8. Open the gas supply valve and water outlet valve (V2).
9. Check for correct operation of the water heater.
16
Detects the flow
located
1 minute passes