Module 2 Test Cooling Study Cards Flashcards
List 10 items that affect the amount of air conditioning needed in a home.
outdoor temp, outdoor humidity, insulation levels, single/double/triple window panes, whether windows are low e, window coverings open/closed, amount of shade from trees, roof overhang, awnings, amount heat generated inside by people, amount of east/west facing glass.
How many square feet can one ton of A.C. cool in Florida?
450 to 750 sgft
How many square feet can one ton of A.C. cool in Michigan?
700 to 1000 sqft
Oversized distribution ductwork is a common problem with central A.C. T/F
False
An undersized AC is better than an oversized one. T/F
True
The typical temperature drop from outdoors to indoors with a properly operating AC system would be about 15 degrees F. T/F
True
What kind of temperature drop would you expect to find in the house air as it passes over the evaporator coil?
15-20 degrees F
A compressor can be thought of as a pump. T/F
True
Compressors are typically located indoors on an air-to-air split system AC system. T/F
False
What is the function of a sump or crankcase heater?
It keeps the oil at the base of the compressor warm enough to boil off the refrigerant
List 8 common compressor problems:
excessive noise/vibration, short cycling/running continuously, out of level, wrong fuse or breaker size, electric wires too small, missing electrical shut off, inoperative, inadequate cooling
The condenser coil in a split system is typically located_.
outdoors
The evaporator coil in a split system is typically located _.
indoors (above furnace)
The condenser fan in a split system is located __.
outdoors
List 4 condenser problems
dirty, damaged or leaking, corrosion, dryer or water heater exhaust too close
List 3 common configurations of evaporator coils.
A-coil, slab coil, vertical coil
Evaporator coils should be upstream of furnace heat exchangers. T/F
False
List 6 common evaporator problems:
no access to coil, dirty, frost, top evaporator dry, corrosion, damage
In 1 sentence, describe the function of a capillary tube
The capillary tube acts as an obstruction in the line, reducing the pressure and temperature of the liquid refrigerant
In one sentence, describe the function of a thermostatic valve.
A TXV, or TEV acts as a more precise expansion device on larger AC or heat pumps.
List 4 common expansion device problems
capillary tube defects, thermostatic expansion valve connections loose, clogged orifice, expansion valve sticking