Hartford Loop

Jim Pompetti

Is there a steam boiler maker , that either suggest or insist , the installation of a Hartford Loop. I know all direction call for one . I have a plumbing inspector that says it is NOT necessary. You input needed.

Dave in QCA

Here is one without a hartford loop

Burnham commercial, for their boilers set up with a boiler feed pump are shown as not requiring a hartford loop.  see page 38 at this link.  http://www.burnhamcommercial.com/products/forced-draft-boilers/v9/io/manual.pdf 



Hoffman specialty, shown at the top of page 3 in the following publication indicate that a hartford loop is not necessary on a dry return system.  http://completewatersystems.com/wp-content/uploads/2011/05/7250.pdf  

These are the only 2 exceptions that I am aware of, but there are probably more manufacturers that would agree with Burnham regarding a feed pump system.



On gravity return systems, where the I&M manual shows "minimum piping requirements" for the installation of a boiler, and that diagram shows and describes the pipes sizes and connections of the hartford loop, it would seem to me that the language is stating that the Harford loop is required by the manufacturer.