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Rinnai Water Heater Goes Cold No Code

Comer6 Member Posts: 1
Our Rinnai Water Heater is 17 Years Old, came with the house had the techs in yesterday because it goes cold intermittently when you shower. Never supposed to run out of hot water. He ran it for 20 minutes, plenty of hot water! last night took a shower it went cold, no code, no beep, nothing. He said the code would come on and it would stay on until the water went off. Tech did nothing. Water does not go cold in the other bathrooms, kitchen??? Any ideas??? Also hot water tastes very irony-that could be the softener which we had serviced already. Any ideas???


  • Larry Weingarten
    Larry Weingarten Member Posts: 2,783
    Hello @Comer6 and welcome! Any chance you have a low flow shower head on the shower that isn't working? Sometimes tankless heaters need more flow to kick on and a low flow head may not be enough. Try just removing the shower head and seeing if the water heats. That would be a clue that the heater's flow switch might need looking at. A cross connection in the plumbing is another possibility.

    Also, I'll suggest you don't drink or cook with softened water. It just raises your salt intake. Instead have your water tested to see what's really in it. That iron taste could come from steel piping.

    Yours, Larry