WorldPeace
Member
I recently installed a Navien NPE-240A. The water temperature fluctuates 20 degrees when I take a shower. Navien currently does not have tech support for homeowners but I was able to troubleshoot and determine the source of the problem.
When I have the tankless water heater set to 125 degrees and I turn on the shower, the burner will kick in for 1 minute and then turn off for about 18 seconds. It will continually cycle like this. I determined the gallons per minute is 1.0.
When I turn on an adjacent hot faucet, the gallons per second will increase to 1.4 GPM and the problem disappears. The burner will stay on the entire time.
So, I've determined that the burner will turn off when the GPM dips below a certain point. I've read that it shouldn't turn off until the flow rate dips below .4 GPM.
Does anyone know how to fix this problem - decrease the flow rate activation rate?
*By the way, I scoured this site for an answer to this. I noticed others had the same problem as mine but I couldn't find an answer. Thanks for any help!
When I have the tankless water heater set to 125 degrees and I turn on the shower, the burner will kick in for 1 minute and then turn off for about 18 seconds. It will continually cycle like this. I determined the gallons per minute is 1.0.
When I turn on an adjacent hot faucet, the gallons per second will increase to 1.4 GPM and the problem disappears. The burner will stay on the entire time.
So, I've determined that the burner will turn off when the GPM dips below a certain point. I've read that it shouldn't turn off until the flow rate dips below .4 GPM.
Does anyone know how to fix this problem - decrease the flow rate activation rate?
*By the way, I scoured this site for an answer to this. I noticed others had the same problem as mine but I couldn't find an answer. Thanks for any help!
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