Navien NCB-240E: Slow to provide hot domestic water

Users who are viewing this thread


New Member
Reaction score
BC, Canada
First time poster, really value the input of this forum.
I moved into a house with a Navien NCB-240E about 6 months ago. Back then, I felt that hot water got to the faucets and shower really fast. Now it seems that the water has to run a long time before it gets hot. I do not know anything about the system, and the yearly maintenance will be done in the fall (I cannot afford a separate call out for this, prices for service are insanely crazy around here; BC, Canada).
Further info: When not using hot water, the display switches between "33.5C" and "9.2 psi". When I open the kitchen faucet fully, it displays "18.1psi" and the temperature goes up. Heating in the house is via radiators that are connected to the Navien.
I know how to change the temperature by pushing "mode" and the temps are 54C for heating and 44C for domestic hot water.
The house is a small, 1400 sqft, one-level house. It is very energy efficient (built by an energy advisor). Kitchen faucet, bathroom sink and shower plus tub faucet, and powder room sink are the only ones that get hot water (plus two cold water faucets outside and in the garage).
I would be very appreciative of any suggestions of fixes I can attempt myself. I have provided pictures of my setup. The house was built in the fall of 2016.
Any suggestions and ideas would be very welcome.


  • IMG_5463.JPG
    71.3 KB · Views: 46
  • IMG_5464.JPG
    34.7 KB · Views: 38
  • IMG_5465.JPG
    77.4 KB · Views: 39
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks