Steam FAQs

Our steam is created from NYC water. The city water is softened using water softeners that are similar to those used in private homes. The softening process adds a trace of salt (regular table salt) to the boiler water but this salt does not evaporate and become part of the steam. Some additional additives are added to the water before it enters the boilers. These additives are all food grade minerals that are approved for this purpose by the FDA and they also remain in the boiler. They do not evaporate and become part of the steam. The steam produced by Con Edison is very pure and is even used by some customers for the sterilization of hospital equipment. Steam may also be used for humidification purposes, for example, in museums, to help protect the art. There is nothing toxic in the steam.

At a minimum, traps should be checked twice a year. Dirt, steam cuts, and warped discs can cause the trap to fail open. This failure causes a steady stream of steam to be discharged into the condensate header. If a trap is allowed to blow, it can cause the premature failure of other traps discharging into the same condensate line by raising the pressure in the condensate discharge header.

Signs of a failed trap include:

• Cold Trap – trap fails to discharge condensate
• No condensate or steam coming to trap – plugged strainer, valve closed in line to trap, or pipe line/elbows plugged upstream of trap
• Worn or defective mechanism
• Trap body filled with dirt – install strainer or remove dirt/blowdown, and
• Trap constantly discharging: trap valve fails to seat, trap too small

We are responsible for all traps before the steam meters. All traps after the steam meters are the responsibility of the building owners. We provide behind-the-meter services that include steam leak repairs and trap maintenance inspection.

Large buildings use machines called chillers to provide the cooling effect. A chiller removes heat from a liquid (typically water). This chilled water is then used to cool and dehumidify the air. Chillers use two methods to cool the water. These are called the vapor compression and absorption refrigeration cycles. Both methods evaporate a refrigerant at a low pressure and condense the refrigerant at a higher pressure.

The vapor compression cycle uses a mechanical compressor to create the pressure difference necessary to circulate the refrigerant. This is the same technology used in home window air-conditioning except that a steam turbine replaces the electric motor to drive the turbine. One advantage to using steam is that a building uses less electricity during peak periods.

In the second method, the absorption cycle, water is evaporated to provide the cooling and is then absorbed by a salt solution. Steam heat can be used to boil off the water in order to start the cycle again. Besides saving electricity, absorption chillers do not use chemicals that can harm the ozone layer, which the vapor compression method frequently does.

Our steam heating system is typically turned off in April and turned back on in October. You will be charged for each turn on/turn off as outlined in our tariff:

Standard Fee: $544 per turn on/turn off (scheduled Monday through Friday from 7am-3pm, excluding holidays)

Premium Fee: $604 per turn on/turn off (scheduled at all other times)

To schedule a turn on or off of your steam heating system, please call our customer service line at 1-800-75-CONED (752-6633) at least 10 business days before the desired date. For any additional inquiries, or to schedule a service, contact us at the phone number provided above.

There are “shut off” valves located in various places throughout the building:

• Outside street service valve
• Inside service valve (ISV, first valve in the building)
• Meter inlet and outlet stop valves
• Trap inlet and outlet isolation valves
• Pressure reducing station inlet and outlet stop valves; and
• Steam equipment isolation valves

EDP meters are calibrated annually. Vortex meters are calibrated every five years.

Shuntflow meters are overhauled every three years.

Behind-the-meter services include repairs, as well as temporary turn-off/turn-on of steam service. We provide 24-hour coverage for special services, including replacement of flange gaskets, valve packing, screwed piping, and welding. An inspection is performed, and a labor and materials cost estimate is provided.

To schedule a steam outage, please call 212-683-8830.

SC-1 All-purpose steam rate for small commercial and small residential accounts such as tailor shops and five-story brownstones.
SC-2 Annual power service for steam heat and/or air conditioning for large commercial office buildings, hospitals, and hotels. Subject to Winter Demand Billing if annual consumption exceeds 14,000 Mlbs.
SC-3 Apartment house steam service for buildings with at least 50% residential and containing at least three or more separate living apartments. Subject to Winter Demand Billing if annual consumption exceeds 14,000 Mlbs.
SC-4 Power service to customers who use steam supplied by the company and another energy source for the same purpose during the winter months. Classified as Back-up or Supplementary Service.
SC-5 Negotiated agreement to retain and attract customers that have viable competitive alternatives to the company's steam service. 

See more information concerning these service classifications.