710 / 710 ASME Service Manual
Ver. 1.00
65
CONFIDENTIAL
12-13. Checking the Flow Rate by Computer Board
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Function
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This function offers a method for checking the flow rate in the water heater’s troubleshooting operations
without having to use the remote controller.
The flow rate check is performed simply by using the “7-Seg LED” on the computer board and the
“Increase” button. The procedure given below can be used to indicate the current flow rate (detected by
the flow sensor) at the “7-Seg LED”. The LED can only display a flow rate range, but this function is
nonetheless useful for the computer board and flow sensor diagnostic purposes.
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Using the function
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1. When in Standby mode right before ignition (cannot be in
combustion, forced-combustion, or the FM adjustment
modes), press and hold the “Increase” button for 5 seconds
or longer to start a display of “A” at “7-seg LED”. Press the
“Increase” button a few times to change the display to “d”.
2. While “d” is displayed, press the “Number display”
button to display the flow rate.
The values displayed at the “7-seg LED” and their
corresponding flow rates are shown in the table below.
7-seg LED display
Flow rate detected by flow sensor
[GPM]
0
0 to 0.4
1
0.5 to1.4
2
1.5 to 2.4
3
2.5 to 3.4
4
3.5 to 4.4
5
4.5 to 5.4
6
5.5 to 6.4
7
6.5 to 7.4
8
7.5 to 8.4
9
8.5 or higher
7-Seg LED
“Number display” Button
“Increase” Button