# Bosch Condensing Tankless



## user2090 (Sep 26, 2009)

I just want to know for my own knowledge. I had to walk away from this job today, because I could not provide the customer with what they needed. Which was a tankless heater repaired for next to nothing. 


Its a two year old Bosch condensing tankless. 

First call-No hot water Code: EA
Long story short-Tech support had me run through a series of checks, rechecks, pressure, blah, blah, blah.....
Tech support is sending out a new board. 

Second call-No Hot water Code: E4 most of the time and EA
Talk to tech support, check sensor, outside vent gas pressure. Tech support says I need to pull the vent and look down in the burner box. Easy for him to say. 
The guy who installed the unit did not leave any room to cut the pvc without having to wreck the wall, then run a new concentric vent outside. When the homeowner finally realized what all was involved and the cost just to try and find the problem, which is highly suspect, she makes the ole  :no:

According to tech support its either a wire-harness or some kind of blockage in the venting. The venting "problem" seems highly unlikely, as I could see inside the vent pipe up to the elbow inside the home. 

We agreed she was better off trying to call a bigger outfit who might have a "Tankless" expert, as we install so little in this area, an expert is hard to find. 

Can someone tell me what the problem could really be????


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## Plumberman (Jul 7, 2008)

Condensate tee installed on vent piping?


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## user2090 (Sep 26, 2009)

Plumberman said:


> Condensate tee installed on vent piping?


No, there is no room for one. Its all drained through the unit. 

This unit has worked for two years until now.


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## 1703 (Jul 21, 2009)

Don't know if it helps, but I have two rinnai's that throw an error in the summer because the vents are right beside an outside light and all the bugs get pulled in and stuck in the burner. Also I have heard of "cotton" from the cottonwood trees doing the same thing.


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## Plumberman (Jul 7, 2008)

Indie said:


> No, there is no room for one. Its all drained through the unit.
> 
> This unit has worked for two years until now.


So it has a condensate trap inside of it that catches the condensate and drains it to a drain line?

The only reason I asked is because I have worked on one that didn't have them installed and it worked for about the same amount of time, then it started flashing error codes.

The condensate had corroded the burner plate and ate up the flame sensors.


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## Evolve (Jan 2, 2011)

I have just installed one recently and yes there is a condensate drain. If you look on the bottom of the unit you will have the drain outlet that you pipe to a drain.


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## Plumberman (Jul 7, 2008)

Evolve said:


> I have just installed one recently and yes there is a condensate drain. If you look on the bottom of the unit you will have the drain outlet that you pipe to a drain.


10 4

I haven't worked on many, but the ones I have seen don't have the integral trap on them. Good to know...


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## Plumbworker (Oct 23, 2008)

ea code is water in the gas valve every time.. but i've never dumped water out of a condensing model though just the 250sx models from 2005 -2009
i believe ea is no flame ionization

im a bosch tankless service provider by the way...

as you can see how everything is nicely layed out and easy to service inside vs a takagi lol..


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