What are two inert gasses
Carbon monoxide and Aldehydes
CO2 and Hydrogen
Carbon Monoxide and Nitrogen
Carbon Dioxide and Nitrogen
What are two products of incomplete combustion
Carbon dioxide and Nitrogen
Hydrogen and carbon
Nitrogen and Aldehydes
In an induced draft burner the fan is
upstream
downstream
forced draft burner
fans are up and down stream
In a forced draft burner the fan is
balanced both down and up stream
in the combustion chamber
In a balanced draft burner the fan is
both up and downstream
is beside the damper
A bi-metal strip is
two strips of separate metal that have the same temperature when heated causes them to curve and is used to control and open an electrical circuit
is two strips of metal welded together with different coefficients temperatures when heated causes them to curve and is used to control and open an electrical circuit
two pieces of metal use for thermostat sensing
A thermistor is
a thermostat
a rod and tube device used in water heaters
a device used to measure room temperature and regulate electrical flow to equipment control's circuit
used to measure the overheating of an appliance
A capillary is
a device used to measure flow rate of appliance
a spring loaded device used operate electrical switches to open or close gas ports. it has a glass bulb at the end that reacts to preasure
a device that operates like a pressure relief vale for water
a device heat value in gas appliances through a glass tube at the end of the device
A rod and tube
is two different metals used in hot water tanks to measure pressure and temperature
is used as a circuit when the temperate rises it activates an electrical circuit
is a device used as a gas line in some cases
is two different metals places inside one another which is used as a thermostat and when heated activates a electrical switch or gas valve port
A thermocouple
is a device used in conjunction with thermostat to measure heat
is used in combustion systems to send moisture information and flue gas reading back to main control board
is used as a safety device as it measures flames in constant pilot and manual reset control devices
shut the system off if there is no gas to the burner
An operating aquastat is
a safety device that measure if water levels high or low
is a device that pumps water when a demand is sent
is a a device that activates in response to water change. it is a normally open switch that will open when water reaches desired temperature inside the boiler
a device that activates in response to water change . it is a normally closed switch that controls temperature of water inside the boiler
A combination high limit/fan control is used to
control the speed of the fan for saftey
sense flue gas spillage for safety
sense air temperature for saftey
senses flow of flue gas through pressure switch
The combination high limit/fan control is a
normally closed switch with a bi metal strip
a normally open fan switch with a rod and tube
a normally open fan switch with on the left and a normally closed high limit switch on the right
a normally open high limit switch on the right and a normally closed fan switch on the left
An operating pressure switch
actuates in the response of high pressure flue gas temperatures
actuates in responce of high temperature in the furnace
actuates in response of change of water, steam, air and gas pressure
actuates in response clogged flue pipe
Operating pressure witches are used on
AC units and refrigerators
steam boilers. water boilers and combustion burners for gas burners
all gas appliances
An operating pressure switch operates by
releasing steam pressure from the tank as steam rises
detects steam pressure and turns off gas to main burner
releasing steam pressure from the tank as water rises
the switch contacts close and energizes a vent motor to release pressure
An air flow switch
detects dilution air flow
ensures air flow such as flu gasses is bring properly vented with differential air flow
ensures that primary, secondary and excesses air is being sent
ensures there is no differential air flow
A flame roll out switch is a high temperature limit switch wired to the burner ignition control. If the flame roll out is sensed the witch is opened and fe-energizes the gas valve.
When furnaces are equipped with draft hoods, they may be equipped with a shut off system that automatically cuts out the main burner when the vent is blocked. These are refereed commonly and incorrectly reffed to as spill switches
What takes place in a heat exchange in a forced air furnace
the flue gasses are stored
gas and air are mixed
the combustion process takes place
return air is heated
inferred haters may not be used in
factories
residential
warehouses
loading docks
Th purpose of a burner in a forced air furnace is to
supply heat directly to the air in the building
heat the combustion air so that the air is lighter to allow it to flow out the exhaust
mix the air and gas
ignite the gas
Atmospheric burners are design to operate under
high air pressure with low gas pressure
normal atmospheric pressure with low gas pressure
atmospheric pressure with high gas pressure
compressed air pressure with high gas pressure
On a roof with a 12/12 pitch and no obstructions the min vent height for a natural gas appliance is
2'
4'
10'
6'
On a roof with a 10/12 pitch and a wall 4' high and 6 feet away from the vent opening, what is the minimum height fora category one propane appliance
3'
Witch term is used to described the natural draft of the chimney measurements at or near the base of the chimney
static pressure draft
neutral pressure point draft
base pressure draft
chimney draft
A damper is a
device used to keep the gasket moist and malleable
plate or valve for regulating the flow of air or flue gas
device used to cool and divert flue gasses
fixed flue gas diverter
Which of the following is an appliance draft control device
a baffle used to control air to a burner
a control used to control air for combustion
a draft hood or draft regulator
a variable damper in the circulating air supply system
Which burner supplies combustion air at sufficient pressure to overcome the resistance of the burner only
power burner
combustion burner
fan assisted burner
What is the name of the device that is installed either internally or eternally to a venting system to extract heat from flue gasses
draft hood
heat reclaimer
draft control device
heat diverter
Which burner supplies combustion air with a mechanical device such as a fan or blower at sufficient pressure to overcome resistance of the burner at the appliance
high pressure burner
mechanical draft burner
Which type of appliance has the combustion products or the flue gasses mixed with the medium being heated
direct fired appliance
space heater
immersion appliance
indirect fired appliance
Which type of appliance does not have flue gasses mixed with the medium being heated
non vented appliance
Which appliance is constructed so that all the combustion air is supplied directly from and the products of combustion are vented directly to the outdoors by independent passageways connected directly to the appliance
direct vented appliance
indoor/outdoor appliances
direct vent appliance
An A vent is
double wall vent with aluminum inside used for main vertical shaft or vent connector
steel of masonry chimney
double wall with stainless steel inside
single thickness of galvanized or aluminum
A B vent is
a steel or masonry chimney
a double wall with stainless inside
a double wall with aluminum inside
double wall with (oval) aluminum inside
A L vent is a
double wall with stainless inside
a single thickness aluminium or galvanized
steel or masonry
venting system under positive pressure
A BW vent is a
a single galvanized or stainless
double wall (oval) with aluminum inside
used for venting systems with positive pressure
A C vent is a
a single thickness galvanized or stainless
double wall (oval) inside with aluminum inside
used for vent with positive pressure
A BH vent is
single thickness wall of galvanized or stainless
For venting BH schedule 40 Thermal plastic PVC/CPVC is used
Three types of thermostats are direct line voltage 120v, 24v and 740ma
Schedule 40 PVC 636 can be used for temperatures up to 60 C/149 F to
CPVC can be used up to and including 90C/194F
The cause of a yellow tipping flame is
the secondary air is reduced
the primary air is reduced
to much primary air
too much dilution air
The bunsen flame or blue flame is is the result of
no premixing of air
perfect secondary air
some premixing of primary air
no excess air
Three types of orifices are Fixed, adjustable and universal
Min and max orifice sizes are
28-32 drill
29-36 drill
29-42 drill
29-40 drill
Using ohms law what reading would be giving if each end of the switch was measures
Using ohms what reading would be shown on the meter if measurement was taken before and after a load
Most common used wire is romex 14/2
What does NMD stand for
Non metal dirt resistant
Non metal dry
Non more drop
Non move drip
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