chapter 13 Flashcards
what is the heat transfer medium used in furnace
metal exchanger transfers its heat to the air which is then circulated through the building
furnace uses what to distribute heat
supply duct
what part of the furnace is responsible for creating air flow
blower fan
what does a forced hot water boiler utilize to distribute heat to a building
pipes that move hot water to radiators by pressure
most common metals for boilers
cast iron and steel
difference between wet and dry base
Wet Based - Combustion chamber is surrounded by water
Dry Base - Combustion chamber is underneath the water
how does combustion area help the flame
reflects radiant heat back at the flame which allows reflected heat to stabilize the flame by vaporizing droplets faster
how are insulating properties of a chamber in a wet base different from dry
Dry Base - composed of insulating material such as ceramic fiber to slow heat loss through the base
Wet Base - insulation is less important because the boiler water is surrounding the chamber.
the heat exchanger of a boiler separates what
hot combustion gases and the boiler water
why does soot build up on heat exchanger affect heat transfer
Less efficient heat exchange because soot acts as an insulator
what is the purpose of baffles or turbulator
to slow combustion gases increasing contact time
what moves water in a forced hot water system
Circulators
how is a steam system like forced hot water
uses water as its heat transfer medium
what causes steam to travel to radiators
the expansion of the steam pushes the steam thru the heating system. (Steam pressure is only used to overcome the resistance the steam meets along the way)
what is the heat transfer medium used in a boiler
heat exchanger heats water that is piped to radiators which provide space heating
