Question about Bosch AquaStar 2400ES-NG

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Bosch 2400E EC code

I have a recontioned Bosch 2400E water heater.
I keep getting EC code. The water heater will ignite , then shut off after a few seconds. This has been going on for about a year ,but I could push the reset button and it would kick on. Now it's hard to keep it going. Also, I can't change the temperture on the contol unit. Could the control unit be the trouble? Where can I get a control unit for the 2400E now that they changed to 2400ES ?

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It sounds more like the gas valve, you can taje the numbers off of it call or e-mail the compant and buy a new one,,, the thermal coupling keeps the piliot lit but i don't get it RECONDITIONED, I have been doing plumbing for 34 years now and to get a water heater thats reconditioned it would probobly be cheaper to buy a new water heater with this kind of problem good luck

Posted on Jun 06, 2009

  • Glenn Collins
    Glenn Collins Sep 10, 2014

    The 2400 does not have a pilot flame it has 2 electrodes that creates sparks to ignite the gas for ionization.


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I have had a Bosch tankless heater now for 8 years I love it!, it is a little slower to get hot water but minimal issue worth the saving on my gas!, for me the only issue is that I need to do is clean the screen on the water inlet since it will stop firing at times or will cut off if to much hot water is needed(this is the sign for me that I need to clean it) (I have well water)

Posted on Sep 15, 2011

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Sounds like they sent you the piece of **** unit I bought new. After I spent a fortune on service calls to fix this piece of sh_t, they finally agreed to send me a new one. Now, the new one after a year of no problems (other than being noisy at start up, but hey, after having to get out of bed EVERY MORNING in January at 5:00am to hit a g-damn reset button by crawling into my crawlspace on the old one) is having the same issue. Oh, by the way did I mention my electric bill went down$40/month but my propane bill went up $60/month? AND IT TAKES EONS TO GET ANY HOT WATER TO ANY FAUCET IN MY HOUSE? AND I'M USING A SH-TLOAD MORE WATER JUST TO GET IT HEATED?
EVERONE I KNOW WHO HAS INSTALLED AN ON DEMAND SYSTEM IS UNHAPPY. Seems like we've been had by the algore nitwits AGAIN!

Posted on Apr 28, 2010

  • Glenn Collins
    Glenn Collins Sep 10, 2014

    I installed a little portable electric water heater fixed under the gas water heater with a little, low power consumption circulation pump that keeps the water going in a circuit. no matter which tap or appliance is using hot water, hot water is instant. I love it!


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