Bosch tankless water heater issues

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Bosch tankless water heater issues

Author: Karbipbaby (IL)

We have had our tankless water heater for 5 to 7 years and never had an issue. Lately, the shower is fluctuating from boiling hot to freezing cold within the first two minutes of a shower. We were getting an error code that indicated the hot water sensor needed to be changed. My husband changed that and it did not resolve the problem at all. He also Descaled the unit. If you flush it out before a shower, you may be lucky to get about five minutes worth of hot water. Has anyone had this issue before and seen it resolved? I really need a nice, long, hot shower!

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Re: Bosch tankless water heater issues
Author: Plumberpalmer (MA) On most tankless water heaters there are multiple tempature sensors one for cold water in hot water out of heat exchanger and out of three way valve. To figure out what one is bad you need to check them with a meter that reads in milli oams
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Re: Bosch tankless water heater issues
Author: Karbipbaby (IL) We were getting the a7 error which indicates the outlet hot water sensor was bad. That is what we replaced. I will see if my husband has a meter to check the other. Even with replacing, the issue continues and we are no longer getting an error in the machine screen.
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Re: Bosch tankless water heater issues
Author: Wheelchair (IL) Tankless Heaters, should be descaled once, and sometimes twice a year depending on the water source. You may have gone thru the process of descaling without actually descaling the Bosch Heater. Best Wishes
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