Exam (elaborations)
Boma hvac.
- Module
- Clin Skills
- Institution
- Clin Skills
Exam of 25 pages for the course Clin Skills at Clin Skills (Boma hvac.)
[Show more]
Seller
Follow
Content preview
Boma hvac✅✅
(T/F) A Compressor raises the pressure and lowers the temperature of the
refrigerant - -False
3 laws dealing with hvac -✅✅-Boyles , Charles, and daltons
A btu is the amount of heat required to change - ✅✅-One pound of water
one degree Fahrenheit
A current magnetic relay opens and closes based on - ✅✅-The current in
the run winding
✅✅-High stability
A desirable physical property of refrigerant is -
A direct expansion - type evaporator is also called a - ✅✅-dry-type
evaporator
A direct expansion type evaporator is also called a - ✅✅-Dry type
evaporator
A fluid is anything that - ✅✅-Flows
A least likely cause of head pressure problems is a - ✅✅-An oversized
cooling tower
A psychrometric chart is a graphic representation of - ✅✅-Thermodynamic
properties
A psychrometric chart is a graphic representation of - ✅✅-Thermodynamic
properties
A pump out unit is used to - ✅✅-Transfer refrigerant from the machine to an
external source
A rotary compressor is what type - ✅✅-Positive displacement compressor
A sensing bulb for a txv should not be Installed ? - ✅✅-On a fitting in a trap
or pocket or on the bottom of the line
,a shell and tube transfers heat - ✅✅-Outside of the tubes to the inside
✅✅
A split phase motor can use what to energize and de-energize the start
winding ? - -Potential relay, current relay, and a centrifugal switch
✅✅
A system which application of heat is the secondary process is -
-Terminal reheat
A systematic check of a cooling unit is - ✅✅-Check the evaporator coil,
condensate pan, tubing for signs of oil leaks, and the electrical wiring
A thermometer indicates - ✅✅-Sensible heat
A ton of refrigeration is equal to - ✅✅-288,000 BTU / 24 hours
A typical evaporator operating temperature in an ac system is - ✅✅-40
degrees Fahrenheit
✅✅
A typical super heat for an evaporator operating under normal conditions
would be - -8 to 12 degrees
✅✅
Acceptable range of resistance to ground when megahoming -
-1000/ohms/volt
✅✅
Adding a small amount of refrigerant to an undercharged system will cause -
-Rise in head pressure
✅✅
Air comes from a hot duct and a cold duct that is supplied by mixing terminals
is called - -Dual duct system
Air conditioning is the control of - ✅✅-Temperature, humidity, purity, and
distribution of the air
Air flow through a duct has highest velocity near - ✅✅-The center of the duct
✅✅
An ac system that provides complete sensible heating and cooling and latent
heat utilization is what type of system - -All air system / all air heat pump
An example of an axial flow fan is - ✅✅-A propeller fan
, An oil safety switch is operated by what - ✅✅-The difference between oil
pressure and crankcase pressure
At a constant pressure, the volume of a gas varies as to the absolute
✅✅
temperature and at a constant volume the pressure of the gas varies directly
with the absolute temperature. This is known as - -Charles law
✅✅
At what locations in a refrigeration system does the saturation pressure
correspond to the saturation temperature - -Evaporator and condenser
Atmospheric pressure at sea level is - ✅✅-29.92" hg
✅✅
Calculations involving heat loads of people take into consideration heat due to
- -Latent heat and sensible heat
✅✅
Can the performance of a fan at various speeds and air densities be predicted
?- -Yea through fan curve calculations
✅✅-A VFD
Capacity control on a chiller is by use of -
Centrifugal compressor is what type - ✅✅-Dynamic
Chillers use what type of compressor - ✅✅-Centrifugal compressor with a
turbine type impeller wheel
✅✅-Ratio of absolute suction and discharge pressure
Compression ratio is -
Compressor motor and condenser fan motor are wired - ✅✅-Parallel
✅✅
Condensing units draw the most amperage when the suction pressure is -
-30 psi
Conductance is a term used to denote heat flow through - ✅✅-Non
homogeneous material
Conduction heat is transferred by - ✅✅-Contact
Convection heat is transferred by - ✅✅-Movement of water fluid or air
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lydiaomutho. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £6.39. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79650 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now