I bought a TITAN N-120 tankless water heater about 3 yrs ago. Now it stopped heating the water. The lights turns on when the water runs, but it does not heat it. I turned the temperature to the highest and now it barely warms the water. Please let me know it there is something that I can do to it to make it work properly and avoid replacing it with a new one. Thanks in advance. :)

Is this setup as a electric, gas or propane heater?

Electric

Do you have a test meter and feel comfortable testing the elements and the power supply wires? Start by testing the incoming power supply, likely 220 but some smaller heaters can be 110. If power is good then go to killing the power at the panels and then verify it is off at the heater. Test the heater elements by disconnecting their supply lines and do a continuity test. There should be continuity, now reconnect the lines and turn the power back on. Test the elements to see that all elements are working, there may be only one but there can be an upper and a lower with a larger 220 unit.

Thanks. That did the job

Glad to be of help. What did you determine was the problem after testing?

I had a similar problem with my Titan N-120 and found a very helpful website with a link to the Top 5 Titan tankless water heater “not enough hot water” problems.

Hi ditgal and welcome to The Plumbing Page at AskMeHelpDesk.com
Very helpful! I added it to my data base, Thank you, Tom