MPO Question?

Singh_5

I will be installing my first MPO shortly.
I noticed the return for the Alliance indirect is seperate from the return
header and is at lower tapping. Why the two different returns? And is it ok to pipe the indirect with other, and just use the bottom tapping for boiler drain.
This is a replacement, so I don't want to reconfigure indirect piping too much.

Singh_5

Glenn Stanton

I will be installing my first MPO shortly.
I noticed the return for the Alliance indirect is seperate from the return
header and is at lower tapping. Why the two different return tappings? And is it ok to pipe the indirect with other, and just use the bottom tapping for boiler drain.
This is a replacement, so I don't want to reconfigure indirect piping too much.

Unknown

Singh

The reason for the seperate indirect tapping has to do with the possiblity of widely varying return temperatures for the heating zones versus the indirect zone. If the heating zones are being reset or are of low temperature orientation, then keep the tappings seperate. If everything is operating as high temperature such as baseboard with normal return temperatures then you can keep them together. The indirect tapping allows the return water from the indirect to short circuit the normal flow of the boiler to just utilize the rear section where water is the hottest to increase the recovery performance of the indirect. Hope this helps. Let us know how you like the MPO when you are done.



Glenn Stanton

Manager of Training

Burnham Hydronics

U.S. Boiler Co., Inc.

Singh_5

Thanks

All Baseboard, but what you say makes sense. Well thought out from Burnham.
I'll post a pic or two.

Devan