Question about Bosch PowerStar AE3.4 AE3.4 Point-of-Use Electric Tankless Water Heater...

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Water doesn't stay hot PowerStar AE3.4

Kitchen sink is all the way across the house from the water heater. Takes forever to get hot water. Put this unit under sink to cure wait. Water gets hot quickly, but after running water for a couple of minutes it is just tepid. Have reduced flow aerator to keep max flow rate in limits. Instructions say it can't be hooked into the hot water line. Why? Seems like that would cure both my problems. Unit will heat up water cooled in piping from water heater and than I get heated water from tank.

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Apparently the software in the brain of the unit is not capable to modulate for smaller heat need and it trigger off the unit when it only need less the 20F temp increase . That is a lack of engineering in the brand unit, and really can not be "fix"

Posted on Feb 02, 2013

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Are you using a single lever faucet? The install guide does indicate that you may need to reduce the input from the cold water side to ensure that water stays at a consistent temperature (see page 7 of the installation and service manual). Also, remember, this is a SMALL hot water heater. So if you're running for any length of time at full output, it may not keep up with you (see page 8 of the service an installation manual). I found the manual online at http://www.airwater.biz/images_templ/bosch-water-heaters-ae3.4-manual.pdf.

Posted on Feb 01, 2009

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