Questions might be asking for a manual, and asks what error A7 means, and asks how to fix error problem, but model number of Bosch heater is not given.
Error codes are start-point for troubleshooting, and can include multiple causes.
So following answer provides general do-it-yourself resources, without saying that problem can be 100% diagnosed or fixed by homeowner.
1) Error code A7 is outlet temperature sensor fault.
Problems include: need for descaling, dirty inlet water filter, debris in faucet aerators, dirty wiring terminals, bad wiring harness, or bad temperature sensor.
2) Before calling service technician who can test failed parts and catch tankless up on yearly maintenance, open following
links for Bosch resources including error codes, phone
number, possible manual, and descaling instructions, and cleaning inlet filter:
3) Product manual: Question posted under model 125HX-LP
Open following link for possible manual:http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/125HXTechSupport/InstallationManuals/tabid/542/Default.aspx
4) Do it yourself service bullitens for 125HX-LPhttp://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/125HXTechSupport/ServiceBulletins/tabid/548/Default.aspx
5) Take a moment and rate answer:
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
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