Are “Hartford Loops” Required on Steam Boilers ?

When you are installing a steam boiler for residential heating, a “Hartford Loop” should be installed on the return to the boiler. Failure to install a “Hartford Loop” will result in a flooded return with water levels in the return piping well above the water levels in the boiler. This flooded return is caused by the pressure generated by the steam in the steam cavity, pushing the water back out of the water cavity and into the return piping system. The movement of the water out of the boiler water cavity will cause the low water cutoff to shut down the burner and activate the water feeder. The end result will be a short cycling burner and inevitably a flooded boiler incapable of producing steam. I have seen this flooded condition so extreme that it caused water to shoot out of the steam vents on the first floor of the building. Installation of a “Hartford Loop” will equalize the level of the return water and the boiler cavity water, enabling the boiler to maintain the pressure difference between the steam and the water cavity. Maintaining these water levels and pressure differential is imperative if we are to have a correctly functioning steam heating boiler.

So...Do your customers a favor. Each time you sell you sell a steam boiler, plan on installing a Hartford Loop to prevent the above mentioned problems and customer dissatisfaction.

Should you need piping diagrams depicting the “Hartford Loop”, please contact your local R.E.Michel Sales Rep. or Branch location.