27
Temperature
Problems
What to do
Display Window
The hot water at the
fixture is too hot.
Are the gas and water supply valves fully open?
[Using the optional remote controller]
Is the water temperature setting appropriate? (page 13)
[Using the optional remote controller]
If the water supply temperature is high, it is possible
for the outlet temperature to be higher than the
temperature set on the remote controller.
[Using the optional remote controller]
If only a low flow of hot water is demanded, it is
possible for the outlet temperature to be higher than the
temperature set on the remote controller.
The hot water at the
fixture is not hot enough.
Are the gas and water supply valves fully open?
[Using the optional remote controller]
Is the water temperature setting appropriate? (page 13)
If the amount of hot water required is very high, it is
possible for the outlet temperature to be lower than the
temperature set on the remote controller.
Decrease the amount of hot water passing through the
unit and the temperature should stabilize.
The actual outlet water temperature is lower than the set
temperature of the unit.
Contact the nearest Noritz agent.
The water is cold when only
a single fixture is open.
The unit will not heat the water if the flow rate is less
than 0.5 gallons (2L) per minute.
Open the fixture more or open other fixtures so that
a greater flow passes through the unit, and the unit
should begin heating again.
The unit does not fire when
water is flowing due to high
supply water temperature.
If you try to supply a low flow of water when the supply
water temperature is too high.
The unit will not fire because it will over heat the outlet water.
Fluctuations in hot water
temperatures.
Clean the water filter of any debris.
(page 22)
[Using the optional remote controller]
Setting temperature cannot rise.
Is the maximum temperature setting appropriate?
(page 14)
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 NR662-OD is 5.3 GPM (20L/min.)
at a 45
°
F (25°C) temperature rise. The maximum flow
available from the NR501-OD is 4.5 GPM (17L/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 22)
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.
Optional Remote Controller
Problems
What to do
Display Window
The light on the power
button does not come on.
Has there been a power failure?
Is the power connected properly?
The water temperature changes
after a power failure or when
the power is disconnected.
The temperature setting and the flow meter alarm
setting may both need to be reset after a power
outage.
The plastic on the surface
or buttons of the remote
controller has torn,
peeled, or air bubbles
inside.
The surface of the remote controller is affixed with a
protective sheet (to prevent surface scratching, etc.) at
time of shipment. This sheet can be removed or left as it
is. When leaving the protective sheet on, areas frequently
touched may tear or peel. However, the remote controller
will not malfunction from water entering such torn or
peeled areas. To restore the appearance of the remote
controller surface, simply remove the protective sheet.
