Cooling System Flashcards
What does SEER stand for?
Seasonal energy efficiency ratio
What is the amount of water vapor that an air-conditioning system must remove from air inside a house before the system can begin removing sensible load heat?
Latent Load
What is the amount of heat energy that an air conditioning system must remove from the air inside of a home because of the temperature of the air?
Sensible load
What is the minimum allowed SEER for most of the United States?
14
What is the seer rating on a older systems?
Ten
What are two air conditioning systems inspectors should disclaim?
Radiant cooling systems
and
absorption coolers
What kind of air-conditioning equipment may be encountered as refrigerators in off grid houses or any other places where electricity is difficult for costly to obtain?
Absorption coolers
Absorption systems use natural gas, propane, or renewable energy for fuel. They use ammonia as a refrigerant and an absorber in place of compressor.
Heat energy flows from someplace ____ going to someplace ______.
Hotter
Colder
Water vapor in the air flows (diffuses) from a place with _____ water vapor to a place with ______ water vapor.
More
Less
Can more water vapor exist in warm air than in cool air?
Warm
What is the stack effect?
Hotter air is lighter than cooler air and will rise
What takes a lot more energy?
1- To change matter from one state to another or
2- To raise the temperature of matter within a state.
One, to change matter from one state to another.
For example: solid to a liquid or liquid to a gas, (or vice versa)
What must be removed in order to change matter from a gas to a liquid and a liquid to a solid?
Energy
Energy must be (added or removed) to change matter from a solid to a liquid and from a liquid to a gas?
Added
The first step in the cooling cycle of an air conditioning system is…
The compressor receives cool gas refrigerant at low pressure from the evaporator coil.
In the cooling cycle of an air conditioning system what does the compressor do?
It changes the cool gas refrigerant at low pressure into a super heated gas and high pressure.
In the cooling cycle of an air conditioning system, liquid refrigerant flows in a liquid line _____ towards the evaporator coil.
Under high pressure
In the cooling cycle of an air conditioning system, what does the metering device do?
Reduces the liquid temperature and pressure and the some of the liquid flashes into a gas
In the cooling cycle of an air conditioning system, what happens to the liquid refrigerant in the evaporator coil?
The liquid expands as it flows through the evaporator coil tubes.
As a liquid in the evaporator coils expand, it absorbs heat from the air inside the house.
The absorbed heat causes the liquid to boil and changes into a cool gas at low pressure
When you see a reversing valve inside the condenser cabinet what does that infer?
That is a heat pump
In a heat pump air conditioning system, what roles do the condenser and evaporator play?
The roles are reversed depending on the heating or cooling cycle.
The outside condenser acts like an evaporator coil
The inside evaporator acts like a condensing coil
How long does it take a air conditioner to reach peak efficiency?
Ten to 20 minutes
If an air conditioning system is too large and is short cycling what function may not be performed?
Dehumidification
At What outside temperature should a inspector not test the air conditioner?
60 degrees or below
What are the two risks of operating an air conditioner below 60°?
Slugging the compressor
In accurate or misleading test results
If environmental conditions are favorable the home inspector may elect activate the system using thermostat. How long should the system operate for maximum effectiveness?
10 to 20 minutes
What is the safe range of outdoor temperature when testing heat pumps?
Between 60 and 80°
When testing a heat pump, how long should you wait between heating and cooling mode?
About five minutes
The package system may be in an air conditioning system and a gas powered furnace, what is that called?
Gas pack
When inspecting replacement condensers in an air conditioning system, What should the inspector be concerned about?
Using components from a different manufacturer
Overcurrent protection device, OPD, may be oversized because new condenser’s require less electricity
What is the typical condenser unit service life?
15 years
Five years in salt water environment
Evaporative coolers are mechanical air intake sources. As such, how far should they be away from contaminant sources such as plumbing vents appliance vents and chimneys?
2- 3- 10 rule
10 feet horizontal or 3 feet below
Should home inspectors report that a normal temperature drop measurement indicates the system is operating as tended?
No
Many home inspectors believe the acceptable dry climate temperature drops is?
18° to 24°
15° to 20° for humid climates
Service access inspection, what is the minimum finished attic access opening size?
20 x 30”
Keyword finished
Service access inspection, the minimum finished crawlspace access opening size is?
22 x 30”
Keyword crawlspace
Appliances located in attic’s should be located within how many feet of the access opening?
20 feet
Appliances located in attics should have a level service space of at least…
30” x 30”
Service access inspection, what is the unobstructed path to the appliance in a crawl space?
22 inches wide and 30 inches high
Keyword crawlspace
Service access inspection, how wide should the passageway be covered by floor sheeting in an attic?
24 inches
Keyword attic
This is different than a crawlspace which is only 22 inches
The primary condensate disposal system pipe should be what diameter and slope?
¾ inch
1/8 inch per foot
Auxiliary condensate management system, one system is a pan placed under the evaporator coil. What size should it be?
At least 1 1/2 inches deep and extend 3 inches beyond the evaporator coil on all sides
Refrigerant line set, manufacturers recommend the maximum support spacing of….
8 feet
Refrigerant lines set, recommend a maximum line set distance of… And maximum vertical distance of…
60 feet
25 feet
Analog thermostat usually use…
A coil bi-metallic spring
Air distribution system design, what is a common reason for temperature balancing problems between rooms?
Inadequate duct size
Air distribution system design, what problems could result from deviations of the industry standards?
Increased HVAC system operating time and cost
Reduced HVAC system service life
Moisture control problems
Air distribution system design, ducts or grills that connect the room to a central hallway return are sometimes called work?
Transfers or jumpers
Air distribution system design, flex duck should be supported by…
1 1/2 inch material at least every 4 feet horizontally and every 6 feet vertically
Air distribution system design, flexible duct support should not sag how many inches per foot?
½ inch
Air distribution system design, must be supported before and after the bend by how much?
Support within 1 foot (or one duct diameter, which ever is smaller) on all sides of the bands and fittings.
Bends in ductwork increase the effective length of a duct. For example, a 90° bend adds how many feet to the affect of length of a duct?
20 feet
Return ducts and inlet, return units should not be located in the same room fuel burning appliances and within how many feet of these appliances?
10 feet
Return ducts and inlet, should not be taken directly from…
Closet, bathroom, toilet room, kitchen, garage, furnace, or unconditioned attic or crawlspace
Home inspectors should consider reporting as information when filters are located in places that are difficult or dangerous to access.
True or false
True
