Buderus vs Alpine

mastercraft

Have installed quite a number of the Burnham Alpines & I really like them!    With the Alpine I can pipe the DHW tank off of the secondary piping, as it is an 'installation option'.    Just installed a Buderus GB, wall hung.  Does the DHW tank HAVE to be piped from the primary loop?   The 'pre made' header has 1" tapping on each  side for the domestic tank.  Can these be plugged & the DHW be piped off of the secondary loop?   

Thanks for any response on this..! 

Aaron_in_Maine

No

No you can not.  The primary pump on a buderus does not run on a call for hot water.  You also have to size the pump according to the size of the boiler and indirect you are running.

mastercraft

thank you but...

Thank you for the response.   So the primary pump doesn't run on a DHW call, but the DHW, being on the secondary side, becomes a call for heat & the primary pump would run.   I didn't wire the DHW sensor in and just kept xx as the integration for the boiler.  The boiler can't differentiate.   

Gordan

Yes, piping DHW as a zone is always an option

And you can make the boiler not know the difference if you want. You can even use a priority relay and still have DHW priority. But you lose the optimized response that the boiler has for DHW calls (rapid ramp-up) vs. space heating calls. On large draws, this could unnecessarily cause inadequate boiler response. Why would you want to do it that way, what's the "win" to offset the loss of built-in smarts?

mastercraft

spoke w' Buderus..

The Rep from Buderus made sense..Said that would work fine in the winter months, however, in the transitional seasons the outdoor reset will keep the boiler maintaining lower temps.  Duh..I should've thought of that.  30 yrs in the biz & I still learn every day!

mastercraft

spoke w' Buderus..

Thank you for the timely responses!!