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Troubleshooting-3
Amount of Hot Water
Problems
What to do
Display Window
The amount of hot water
at a certain fixture is not
constant.
When hot water is demanded at other fixtures, the
amount available may be reduced.
The maximum flow available from the NRC711-DV,
NRC711-OD is 6.3 GPM (24.0L/min.), NRC661A-DV,
NRC661A-OD is 4.9 GPM (18.7L/min.) at a 45
°
F (25°C)
temperature rise.
Pressure fluctuations and other plumbing conditions
can cause the temperature and pressure at a fixture to
be unstable, but it should stabilize after a short time.
There are some types of hot water taps that discharges
large volumes of hot water at first but stabilize after time.
To keep the temperature stable, the heater limits the
amount of water that can flow through it to a low flow
initially, but the amount increases over time.
[Using the optional remote controller]
The amount of hot water in
the tub is less/more than the
set amount when using the
flow meter alarm feature.
When hot water is used for other fixtures while filling
the bath tub, the tub will not fill as much.
If there is water in the tub already, or when filling is
stopped and restarted, the tub will fill more.
[Using the optional remote controller]
The flow meter alarm does
not sound even when filled
to the set amount.
The flow meter alarm is set to sound when hot water is
continuously discharged for the set volume of water.
If mixing valves are used, or if cold water is mixed
with hot water at the fixture, the tub will fill more than
the setting of the flow meter alarm.
Amount of hot water
available has decreased
over time.
Is the water filter clogged? (page 23)
If the supply water is hard and has not been treated,
scale can build-up in the water heater and decrease
the maximum amount of hot water available. Scale can
be removed from the water heater by flushing the unit
periodically. To prevent scale from forming in the water
heater, a water softener or scale inhibitor is recommended.
