Heating Sources and Refrigeration Flashcards
Natural gas is
Most common
Electricity is
Most expensive
Fuel oil/diesel may be used
in rural locations and is more common outside US
Liquefied Petroleum (LP)
may be used in rural locations
Steam
used in some urban areas (and on Cornell campus by Statler Hotel)
Centralized for heating
for heating, use a boiler to produce hot water and sometimes steam
Heat exchange or heat transfer
when two objects (typically liquid) come near each other and exchange heat
Centralized for chilled water
supplies cold water for water-based centralized HVAC systems
Secondary water
water used for heating and cooling
-chilled water supply and return
-condenser water supply and return
Refrigeration or vapour compression cycle
a circulating refrigerant removes heat from one location and transfers this heat to another location where it is rejected
Heat removal occurs in
the evaporator
Heat is rejected in
the condenser
The compressor provides
the energy necessary to accomplish this heat transfer
The expansion valve controls
the flow of refrigerant through the system
Chillers (and all refrigeration equipment) rely on the
refrigeration cycle
