All houses and buildings in the greater New York area that are used all
year have a heating system. The heating system keeps the building
comfortably warm during the cold winter months. The most common heating
systems in this area are forced hot air heat, hot water (or hydronic)
heat, steam heat, and heat pumps. Fireplaces, coal-burning stoves, and
wood-burning stoves provide supplemental heat in some buildings. The
source of fuel for the heating system can be oil, gas, or electricity.
Forced Air
In a forced hot air heating system, the heat exchanger in a furnace is
warmed by burning fuel. A fan circulates air from inside the building
over the warm heat exchanger. This warmed air is then circulated
throughout the building. This process heats the building.
In some buildings, forced hot air heating ducts are also used for
cooling. Since heating ducts are best placed at floor level, and cooling
ducts are best placed at ceiling level, the situation is far from
optimal.
Hot Water (Hydronic) Heat
Water is heated in boiler, usually to between 160 and 180 degrees
Fahrenheit. Pumps circulate the hot water through pipes in the building.
This heated water warms radiators placed in the rooms. These radiators,
in turn, warm the air in the room.
In some homes, pipes are buried in the concrete slab. This is type of
system is called radiant heat.
Many people prefer (hydronic) hot water heat, because the radiators are
small, the system typically quiet, and it can be easily divided into
multiple zones. Hot water heat has made steam heat obsolete in homes and
smaller buildings.
Steam Heat
Steam heat is an older style heating system, typically installed in
buildings constructed before the 1950s. Water is heated in a boiler
until it becomes steam. Steam, which is a gas, rises through the pipes
into radiators. The steam causes these radiators to become hot. These
radiators warm the air in a building.
Steam heat is noisy, and buildings with steam heat often warm unevenly.
The pipes used with steam heat have a long life expectancy, and the
piping typically used for steam system is not readily c onverted to hot
water heating systems. If your house was built with steam heat, it is
probably not cost-effective to convert it to hot water heating.
Although steam heat is rarely installed in new homes or small buildings,
it is often the heating system of choice in a high-rise building. This
is because of the difficulty in pumping hot water to the upper levels of
a high-rise building.
Heat Pumps
Essentially, a heat pump is an air-conditioner working in reverse. In
the summer, a heat pump functions like a normal air-conditioner. In the
cooler months, the heat pump can be operated in a reverse mode. In this
reverse mode, the heat pump heats a building by extracting the available
heat energy from the outside air or underground water.
When the outside temperature falls below freezing, the heat pump can no
longer effectively extract heat from the air. Below freezing, the heat
pump relies on an internal electric heating coil. In this mode, the heat
pump can be quite expensive to operate.
In the greater New York area, the heating season usually runs from
October through April, and the cost of electricity is relatively high.
For these reasons, heat pumps may not be the most economical way to heat
a building. However some buildings have no oil or gas available. This is
often the case in newer condominium unit developments. In these
buildings, some sort of electric heat is needed. Where electric heat
must be used, the heat pump is the most economical choice. |