Posted by Roger on May 01, 2000 at 06:40:06:
In Reply to: Hartford Loop posted by Keith on April 30, 2000 at 07:07:43:
: The Hartford loop was a valuable tool in the days of gravity return steam systems but is it of any value today? If installed in conjunction with a forced feed system (condensate return tank, feed pp etc) the Hartford Loop is a detriment to safe boiler operation.
: If the check valve in the condensate line between the feed pump and the boiler fails, or leaks, the boiler will force the boiler water out of the boiler and into the condensate return tank resulting in boiler failure or explosion. I open this subject for discussion because a reputable boiler mfg. recommends using a Hartford Loop when installing their CIS L/P stm boiler with a forced condensate return system.
My first response is to follow the manufacturers instructions. However I am like you in thinking that with a boiler feed pump and tank the loop is not necessary. However, I would highly recommend that a vent line and overflow line be installed to prevent pressurization of the normally atmospheric tank. Also the check valve between the boiler feed pump and boiler inlet is a must.
If the steam line pitches back to the boiler and is piped in a way that it returns to the piping of the Hartford loop then I could understand the need for the loop.