How to choose the right Steam Heating Control

Temperature averaging controls are usually the best choice.  In order to choose the appropriate steam heating control there are several other factors to consider:

Is the building truly centrally heated?

This means there are no thermostatically operated radiator valves, no steam zone valves off the main steam lines, and no air handlers or fan coil sub-systems which draw heat from the main steam lines. Two or three sensors will control from two to nine apartments (Model RD1403), four sensors will control up to 20 apartments (Model RD1404), and six or seven sensors are recommended for 21 or more apartments (Models AH207 and RF207).

Are there air handlers or thermostatically operated radiator valves in the majority of the living spaces?

If so, a steam duty cycle control may be the most reliable bet, although room sensors placed in hallways have been known to work. Under certain circumstances, placing sensors in the spaces that are heated by the cast iron radiators even though there are air handlers in other zones may still work.  But, this may result in cold air coming off the air handlers in-between heating cycles.  If only a small percentage of the apartments have thermostatically operated radiator valves, then place the heat sensors in other apartments.

Does the building have concrete floors or other impediments to running wire?

If so, the (Model SF201) steam duty cycle control is certainly a practical and economical solution.  More information about the (Model SF201) is available by downloading either the brochure supplement or the more technical manual.

R & D Electronics Inc. engineering offers many models and options for controlling buildings with one hundred or more apartments.  Large buildings typically have full modulating steam boilers and in some cases, steam pressure must be maintained through out the day (Model CB200),  (Models AH207, SF201 and RF207) are capable of staging two boilers by turning “on” both boilers, then the “lag” boiler is dropped “off” as room temperatures begin to rise a small amount.