Troubleshooting; Solving Basic Problems - Navien NFC Series User's Information Manual

5. Troubleshooting

5.1 Solving Basic Problems

If you experience a problem with the boiler, refer to the following
chart for possible remedies. Error codes that appear on the front
panel display are explained in the following section.
For minor problems, resetting the boiler may resolve the issue. To
reset the boiler, press the Back button (
If resetting the boiler and attempting the remedies suggested below do not resolve the problem, contact an authorized technician, a licensed
professional, or Technical Support at 1-800-519-8794 for service instructions.
Problem
No water comes out when the hot
water tap is opened.
The water from the hot water faucet
is cold or turns cold and stays cold.
The water from the hot water faucet
is not hot enough.
The water from the hot water faucet
is too hot.
Space heating side malfunction
20 Troubleshooting
) on the front panel.
Possible Cause(s)
Is the cold water inlet filter clean?
●
Is an error code displayed on the front panel?
●
Is the boiler frozen?
●
Is the hot water faucet open wide enough
●
draw at least 0.5 gallons of water per minute
(GPM) through the boiler?
Is an error code displayed on the front panel?
●
Is the set temperature too low?
Is the set temperature set too high?
Is the setting temperature too low?
Is there power to the system, or is the system in
stand by?
Is the system running for domestic hot water
(DHW)?
Is the filter on the heating side restricted?
What to do
Ensure that the shut–off valves on the hot and
●
cold pipes are open.
If an error code is displayed, refer to
●
"5.2 Understanding Error Codes" on page 21.
If an error code is displayed, refer to
"5.2 Understanding Error Codes" on page 21.
Check the boiler's temperature setting. Refer to
●
"3.2 Adjusting the Temperature" on page 9.
Check for cross piping between the cold and
●
hot water lines.
Check the boiler's temperature setting. See "3.2
Adjusting the Temperature" on page 9.
Check the boiler's temperature setting. See"3.2
Adjusting the Temperature" on page 9.
Make sure the power is on, and plugged into the
outlet with the correct voltage. Press the Power
button and raise the setting temperature. Make
sure the boiler is turned on.
When the unit is heating for DHW, the heating
side does not work.
Clean out filters that belong to the heating side.