Question about Bosch AquaStar Indoor Natural Gas Tankless Water Heater with Vent Hood #125

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No hot water

The grid lights up but no hot water only luke warm also a small water leak is coming out of the valve from the cold water intake.

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  • albert getty
    albert getty May 11, 2010

    is it hooked up backwards more then ten people have had simuler problems no one ever answers me on this ? can you please let me know? I have a feeling that becuse this is a newer product some plumbers are installing wrong lets say you are hooking one up on the wall infront of you and to the left in the corner where it just so happens the water input is comeing from so it gets hooked up this way but in truth the water input for the waterheater is on your right? do you also have low water pressure when unit is on? if so it would explain my thoughts on this where the hot water is pushed backwards through heater causeing low warter pressure and heat and in cases where there is a pump in heater leaking . thank you if you can help me with this please leave your name and I will add your name to my finding thank's again Albert



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Our will start clicking and stop. it does not light unless we smack on the tank a few times

Posted on Aug 06, 2009

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If the leak is behind the handle take the handle off and tightn the packing nut, do not over tighten, as far as luke warm water is this with just one facucet on, they way these tankless water heaters work they are by gpm, gallons per min, if you have more gallons of water going thru the unit then it is designed for then it won't get hot, if your water pressure is to high going thru it will push it to fast thru the unit and won't get hot, your house pressure should be no higher then 75lbs no lower then 65lbs

Posted on Jun 06, 2009


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