Notes J6-J10 Flashcards
Fan-assisted BURNERS overcome the resistance of the ________ only. Remaining flue gases ________ draft out.
Burner
Naturally
Fan assisted APPLIANCE has a draft through the entire appliance and is not equipped with? and do not need ________ ____
draft control
dilution air
Draft control requires ________ ____ and is not part of the combustion process
dilution air
Fan assisted burners require?
draft control and dilution air
Dilution air is ___cuft per 1000btuh
15cuft
Natural draft depends on the _________ of the flue gases. It also requires _________ and _________ air
buoyancy
combustion and dilution
Natural draft appliances typically require which type of venting?
B vent or chimney liner
Fan assisted burners provide higher combustion ________
efficiency
Fan assisted burner regulate the ________ air supply fore the burner only
combustion
In a fan assisted appliance, the fan does not develop _____ pressure. It still depends on ________ for draft
vent pressure
bouyancy
What device is equipped above a burner in a fan assisted burner appliance to aid in buoyancy?
neutralizing device
Fan assisted burners are also equipped with _____ _____ to prove the burner fan is on
flow switches
Why are fan assisted appliances more susceptible to condensation?
Because they provide lower flue temperatures than natural draft
What is the vent connector?
Attaches the appliance to the chimney
Vent connectors can be B or C vent. True or False?
True
Vent connectors may or may not include draft control. True or False?
True
The main/common/chimney vent, may only be __ vent
B
Common vent must be __ vent
B
No reducing vent connectors may be used. True or False?
True
Max lateral length is __” for every 1” diameter of common vent pipe
18”
Draft is created through a _______ or _________ difference in the system
pressure or temperature
Draft is mainly affected by?
Height and temperature
In draft, as height increases, pressure _________
decreases
The longer the chimney, the greater the pressure difference which results in ________ draft
greater
Greater height creates more hot gas and rise. True or False?
True
In dampers, a _____ or valve regulates the flow
plate
Gas appliances require flue with draft control to remove what?
products of combustion
What are the three purposes of a draft hood?
- Neutralize stack effect
- Provide dilution air
- Provide spillage relief
Dilution air ____ and ____ the flue gas
slows and cools
Propane tanks are ________ and cylinders are __________
stationary
portable
LPG gases are made up of?
Propane and butane
LNG stands for?
Liquid natural gas
Propane tanks up to 1000USWG are built to what spec? (Abbreviation)
ASME
Propane tanks range between 120USWG and ______USWG
1000
All propane tanks have what certification that explains which province or territory in which they can be installed?
C.R.N
Cylinder sizes range from __lb to _____lb
1 to 420lb
1lb camping cylinders are non-refillable. True or False
TRUE
Can gas cylinders be laid on their side?
NO
Why can gas cylinders not be laid horizontal?
The safety valve is immersed in liquid
Cylinders must undergo re-qualification every __ years
10
Length of the dip tube on a fixed liquid level gauge indicates the max level the cylinder can be filled. True or False?
True
What is the purpose of the 80% refill rule?
To leave 20% space for vapour
It is practical to stop re-filling a cylinder when?
Liquid comes out of the spit valve
Where can you find the information on how long of a dip-tube to install for a specific cylinder?
By the marking on the neck of that cylinder
Vapour service is POL ______ threads and Liquid service is POL _____ threads
female
male
Tanks have a pressure rating of ____ or ____ psi
250 or 312psi
Cylinders have a rating of ____ psi
375psi
A vehicle tank pressure rating would be ____psi and a home tank would be ____
312psi
250psi
Cylinders have ____ valve, tanks have _______
one
multiple
Less liquid level in a propane cylinder/tank causes additional vaporization which causes what?
a wetted surface
As demand for vapour increases, what is required ?
additional heat
Sweating of the tank, due to a low liquid level, acts as an insulator which makes it even harder to boil. True or False?
True
At -45F, there is zero vapour pressure. True or False?
True
In the winter, why is crucial to have a high level of liquid?
To aid in vaporization due to low ambient temperatures
Two questions you must ask when sizing propane storage?
how fast can we turn liquid to gas?
what is the ambient temperature?
Where can information on underground installations be found?
Annex H
Natural gas is stored at ____f, slightly _____ atmospheric pressure
-260f slightly above
Propane cylinder re-qualification must be done by an organization approved by ?
DOT/Transport Canada
It is against the law to refill an outdated cylinder. True or False?
True
Tanks that have been re-qualified will have what marking?
An E on the end date
On permanent tank installs, the regulators are installed where?
First stage at the tank and second stage at the house before entry
How does two-stage regulation reduce freeze-ups?
It mitigates extreme pressure drops
Freeze-ups occur between what temperatures?
35-45f
First stage regulators are normally what colour?
Red
Second stage regulators are normally what colour?
Green
Bonnet vents shall be pointed _______ outdoors. EXCEPT WHEN INSTALLED IN A DOME
downward
When final stage regulator is not equipped with internal relief. One must be installed immediately downstream. True or False?
True
Wood is not acceptable to stand cylinders on. True or False?
True
A hydrostatic relief is for liquid propane lines only. True or False?
True
Vapour is what is needed to provide btuh. Use _________ to help meet your load demands.
Vaporizers.
Underground installations are relatively constant due to?
Constant ground temperatures
Orifices must be cleaned:
a) small brush
b) small file
c) solvents
c
Digester gas is considered a renewable resource because?
generates no net co2
Intermittent pilot means the pilot burns the entire cycle. True or False
True
What is the max pressure a b fitter can work on?
a) 5psig
b) 100 psig
c) no limit
c)
CEUL is not recognized in BC as being qualified. True or False?
True
If the exhaust vent is blocked the ________ will not allow the burner to run
inducer
Orifice size controls the _________ of gas
volume
Second diaphragm controls?
downstream pressure
Under normal conditions, what tells the fan to shut off in a furnace?
temperature cools down
Vent termination shall 90 and turn _________
downwards
Low water and low gas supply are examples of a limit and a safety. true or False?
True
