MrCool MHWH199NC U Series, Руководство по установке

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1. Connect the empty connection of the isolation valve on the
cold water side to the outlet of the circulation pump.
2. Connect the empty connection of the isolation valve
on the hot water valve to the solution tank.
3. Connect the inlet of the circulation pump to the
solution tank.
4. Make sure there’s no leakage in any of the connectors.
5 . Fill the solution tank with descaling solution. (It’s
recommended to use white vinegar as a descaling
solution. However, if using commercial descaler,
please properly follow the instruction of the
descaler manufacturer.)
6. Turn the isolation valves and make sure the water
loop is switched to the circulation loop.
7 . Run the circulation pump until the solution that comes out
from the hot water side is clean.
8. Drain the solution from the unit.
9. Disconnect the pipes/tubes for flushing and close the empty
connectors of the isolation valves.
10. Turn the isolation valve and switch to the normal water flow.
11. Restore the power supply, gas supply and the water supply.
12.
Run the water heater for several minutes to make sure
there’s no solution remaining in the unit.
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Troubleshooting
The water temperature is
not hot enough or turns cold
during operation.
The water is not hot enough.
Is the faucet open enough to draw
at least 0.66 gallons (2.5 liters) per
minute through the water heater?
Open the faucet to allow more
water flow.
Refer to the error codes &
solutions section on the
previous pages.
Adjust the outlet water
temperature.
Is an error code flashing on the
display panel?
Is the outlet water temperature
set too low?
Is the water temperature set
too low?
Adjust the temperature setting.
The water at the faucet is
too hot.
Is the water temperature set
too high?
Adjust the temperature setting.
A fan can be heard even
when the unit is not
operating.
The fan continues to operate after
the burner shuts off to clear the
exhaust vent of combustion gases.
This is a normal pre-purge or
post-purge operation, no action
is required.
White smoke can be seen
coming out of the exterior
exhaust gas vent.
Depending on the outside
temperature, water vapor can be
produced as the exhaust is vented.
This is a normal operation, no
action is required.
Issue Possible Causes Possible Remedies
Diagnostics and Suggested Corrective Actions
The water heater control panel is able to record information about the water heater’s operating condition at
the time of the ten most recent faults or errors. This information is available to view in the error code history
when accessed in the After-Sales Mode. The following screens will be displayed when reviewing the water
heater history. The table below also includes diagnostic information and possible corrective actions.
Nothing appears on
the display panel but
the unit beeps.
Main control board is
not receiving
commands.
Check the wiring to
ensure it is correct and
there are no
short-circuits.
Correct wiring per wiring
diagram, including the
connection of the
transformer to the control.
Nothing appears on
the display panel and
no other components
are operating.
No 120V power supply
is being received.
Ensure the power
button on the display
panel is turned ON.
Turn on the power button
on the display panel.
Display repeatedly
goes through
initialization
sequence.
Occurs when power
supply is abnormal.
Power supply voltage
too low.
Switching power is
malfunctioning.
Turn on the power button
on the display panel.
Replace the MAIN
CONTROL BOARD.
Is there 120V at the
distribution box?
Troubleshoot and correct
the power supply to the
distribution box.
Is the power connector
on the MAIN CONTROL
BOARD disconnected?
Properly connect the
power cable to the MAIN
CONTROL BOARD.
Inspect the fuse. Replace the MAIN
CONTROL BOARD.
Display Condition Diagnostic Possible Corrective
Actions