Posted on Jan 30, 2009

Bosch AquaStar 2700ES NG - C7 error

I installed the unit myself and on power on got a C7 error msg.
According to the manual, the primary fan is not rotating.
I checked the power supply and grounding as well as visually inspected the unit inside to make sure there are no loose cable connections.
Any help is appreciated.

gtodorov Feb 01, 2009

Fixed the problem myself.

The cables in the control panel attach to the PCB board with connectors that are little flaky.

The pins in the connector on the multi-wire cable feeding the primary fan were bent outwards and were not making contact with the copper fingers on the PCB board. All it took to fix the problem was a screwdriver and a pin to adjust (bent inwards) the connector pins.

Overall, a great unit after two days of use but I didn’t expect to have to take it apart to make it work. It’s German engineered after all.

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Anonymous

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Posted on Jan 30, 2009

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Hope this helps. Be careful of electrical shock!
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/2700ESTechSupport/Troubleshooting/tabid/1288/Default.aspx
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