Rinnai tankless water heater runs cold

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Rinnai tankless water heater runs cold

Author: Jane in AZ (AZ)

Rinnai model REU-KBP3237FFUD-US heats water for about 30 seconds, then goes cold. There are no error codes, nor have there been power outages. We are in a remote area and can’t get a plumber scheduled until next week. We have tried rebooting ( turning it off and on a couple of times ) which seems to occasionally help a little. The unit is four years old, parts still under warranty. We have a water softener. Could this be some kind of short in the system? A problem with the electronic “brains”? Defective heat exchanger? I have contacted Rinnai, no help there. Any ideas are appreciated. Thank you!

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Re: Rinnai tankless water heater runs cold
Author: srloren (CA) Contact the President of Rinnai and tell him or her what your problem is and ask why they will not help you resolve it. Good luck.
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Re: Rinnai tankless water heater runs cold
Author: Paul48 (CT) Make sure the plumber you have coming has been trained to work on the unit.
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Re: Rinnai tankless water heater runs cold
Author: packy (MA) two things. when the water turns cold, do not shut it off. go immediately to the heater to see if there is an error code. next to try... look online for a video about how to clean the rinnai inline water filter.
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Re: Rinnai tankless water heater runs cold
Author: hj (AZ) After 4 years the coil may need "deliming", which is normally a yearly process.
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