The primary control system starts or stops a boiler or boilers or opens a motorized valve
in a system that purchases steam from an energy supplier. The source of steam does
not make any difference. Starting a boiler or opening an automatic valve allows steam to
flow into the buildings radiation system. The flow of steam is controlled in accordance with changes in the outside temperature. The colder it is outside; the control system allows more steam to enter the building distribution system.

Our control system expands on the basic control as follows:
When the primary control calls for heating service, steam is admitted to the building
distribution system and steam pressure builds up over a relatively short period of time.
Our system will sense this increase in pressure. We will sense the steam pressure at the end of the distribution lop in the basement. We will determine by test what the steam
pressure at that point will be to ensure that the radiation at the furthest point from the source of steam on the top floor will be hot. At this point the radiation can continue to deliver heat to the apartment rooms with the source of steam shut off for a short time. In this short period of time, the hot cast radiators continue to deliver hear. At the end of the timed 'off' period, our system will re-activate the main control and the steam supply to the system is continued.

Our system does not change the main control cycle, it only interrupts it to allow a delivery of heating service without steam being delivered to the distribution system from the steam source. With our system in operation, the steam supply to the distribution system is steady, but the steam input from the source to the distribution system is not continuous. In this manner, a reduction in steam consumption can be achieved.

After a period of testing of a steam heating system with cast iron radiation, we found that the cast iron absorbs a great deal of heat energy quickly because it is a good conductor of heat and it has a relatively high mass. In our test building, the primary control was a room thermostat. In this structure, we were able to reduce the cost of fuel for heating by 30% without any reduction in comfort.

This control system can be installed in an existing building without any disturbance to the
occupancy and without any shutdown of the main system required.