Navien CR-180 Installation Manual page 59

I
Service
G ENERAL TROU BLESHOOTIN G
PROBLEM POSSIBLE SOLUTIONS
It takes a long time to get hot water to the fixtures.
� C ircul ation pump is in F reeze protection mode . C ircul ation pump needs to change hot water
circul ation mode .
The water is not hot enough.
� C heck ground water temperature first and sy stem setting temperature .
� C heck cross pl umbing between col d water l ines and hot water l ines .
H ow? Shut off Main col d water suppl y v alv e to water heater, which means no water suppl y
to water heater . Open any hot water faucet . If col d water comes from hot side faucet, there
is cross hot and col d water l ines somewhere in faci l ity .
� Is the gas suppl y v alv e full y open?
� Is the gas l ine sized properl y?
� Is the gas suppl y pressure enough?
� Is the set temperature too l ow?
The water is too hot.
� Is the set temperature set too high?
The hot water is not available when a fixture is opened.
� Make sure the unit gets 1 2 0V 60Hz power suppl y .
� Is the gas suppl y v alv e full y open?
� Is the water suppl y v alv e full y open?
� Is the fi l ter on col d water inl et cl ean?
� Is the hot water fi x ture sufficientl y open to draw at l east 0 . 5 G PM through the water heater?
� Is the unit frozen?
� Is there enough LP G gas in the tank?
The hot water turns cold and stays cold.
� Is the fl ow rate enough to keep the Model 3 5 - 1 running?
� If there is a recircul ation sy stem install ed, does the recircul ation l ine hav e right check
v alv es?
� Is the gas suppl y v alv e full y open?
� Is the fi l ter on col d water inl et cl ean?
� Are the fi x tures cl ean of debris and obstructions?
� C heck cross pl umbing between col d water l ines and hot water l ines .
Hot water temperature fluctuating.
� C heck incoming col d water pressure whether it is too l ow . ( needs minimum 1 5 PS1)
� Is the fi l ter on col d water inl et cl ean?
� Is the gas l ine sized properl y?
� Is the suppl y gas pressure enough?
� C heck for cross connection between col d water l ines and hot water l ines .