residental heating, systems and equipment (110104g) Flashcards
What type of fuels do furnaces use?
Natural gas
Propane gas
Oil fuel
Solid fuel aka coal wood
How many types of burner assemblies are there and what type?
There are two Upshot and Inshot
What are the heat values of propane and natural gas?
Propane 2500 btu
Natural gas 1000 btu
What does btu stand for?
British Thermal Unit
What is used in high efficiency furnace in place of the draft hood.
Inducer motor
What are some types of safety controls for furnaces?
Highlimit
CAD sensor censes light
What type of furnace has the return air on top and supply air on bottom?
Counter flow
What type of furnace has return air on the side and supply air on top?
Upflow common use
What type of furnace has both return and supply on top of the unit?
Lowboy furnace
What type of venting must be used on a high efficiency furnace?
Plastic 636 pvc as there is asidic chemicals in the condensation of a high efficiency furnace
What type of furnace is 78% efficiency
A mid efficiency
What type of furnace is 78% or lower
A low efficiency
What type of furnace is 88% efficiency
High efficiency
what is the heating value of electricity compared to BTUH
1 watt = 3.413BTU
What are the two types of oil burners?
Vaporizing and Atomizing
what oil burner is most commonly used today?
Atomizing
what are sold fuels comprised off?
Wood Coal and Wood pellets
What else is required for fuel to burn?
Oxygen
where are some locations were air is required to burn fuel in the combustion process?
Air shutters, gas burners
what is dilution air?
Air with contaminants that is cooled down in the draft hood before being expelled out.
What is the main use of a heat exchanger?
allow the bad contaminants like co2 to escape without combining with the supplied air that heats the home
What is a (CAD) sensor
(CAD) is a cadmium sulfide cell. this scene lights in furnaces that use solid fuel.
what are the types of blower’s in a furnace
Direct drive and belt driven
what is used in place of a draft hood for fuel furnaces as well as oil furnaces ?
Barometric damper`
what does a furnace rely on even with and inducer motor to vent out?
Buoyancy
what does a high efficiency furnace must have that others don’t?
Inducer motor
plastic venting
secondary heat exchanger
what are the two types of fan coils?
Electrical or Liquid medium
what is the recommended humidity in the home?
30-55%
what does static electricity indicate?
that there is not enough humidity
what are the types of humidifiers
there are four types
_ Pan evaporators
_ Bypass drum type
_ Bypass flow thru
_ atomizing
what type of pads does a pan evaporator use?
wicking pads
what is a humidistat?
a moisture controlled switch
what are three main components of a Ac system?
- Evaporator coil or A coil
- condenser unit
- compressor unit
What should never be connected into and HRV system?
Range hoods and dryer vents
what does HRV stand for?
(HRV) heat recovery ventilator
what is CFM?
(CFM) is cubic feet per minute
what is the most common type of HVAC plenum system?
extended or reducing
what is combustion air?
Combustion air is the air an appliance needs to replenish, for the air to be exhausted so that a vacuum effect doesn’t occur. Also helps to keep oxygen going to help with combustion
what are byproducts of combustion?
- carbon monoxide
-oxides of nitrogen
-unburned carbon
-soot
what type of venting does a solid fuel furnace use?
a-vent
l-vent
masonry chimney are also allowed
why do we need to vent buildings?
TO remove excessive moisture and to rid the house of combustion type gas
what does exfiltration mean?
the air that escapes through gaps in the building like opening a window
what does infiltration mean?
air that shapes in the building like through a window unwanted draft
what is the required gas-to-air ratio for natural gas and propane gas?
10:1
what is a cord of wood sold in?
4’ x 4’ x 8’
what kind of switch is a thermostat?
Temperature sensing
what is a radial HVAC system?
octopus-looking one that uses a counterflow furnace and is easy to install.
when does and extended plenum have to be reduced?
after a maximum of 24’
when is an appliance direct vent appliance?
when there is a combustion air hook up
high efficiency furnaces are also known as what?
condensing furnace
Three types of fireplaces?
-Built-in
-free standing
-gas insert
