Two boilers with a gravity return

Joe B.

Do you need to pipe two steam boilers with a common gravity return like a pumped return? Do we need to add a receiver tank with two pumps or one pump and motorized valves? Or can we just have motorized valves and no pump or tank? They are Burnham's IN 7 boilers. any info would be appreciated.

gerry gill

you can install them as a gravity return,

or as a pumped return..which do you prefer? if you wish a pumped return, then the Burnham Heating Helper book has excellent details on how to do this..for gravity return install as usual..just ensure there is valves to isolate for maintenance and most importantanly, ensure the boilers are level with each other so that the water lines are at the same place..

The Steam Whisperer (Formerly Boilerpro)

Something like this.....

Here's a pair of Slantfins piped for gravity return per their installation manual.    Waterlines are little wild initially until they get cleaned up some, then thier fine.  This pair ran such dry steam that there was not any carryoever at all to the header, so the primaryu probe type LWCO (on the right) didn't work because the probe was in pure steam condensate.  We ended up going to a high sensity control to deal with the problem.  The mod steamer I put in last fall had a similiar problem,  only solution was to use a float type LWCO.