Answers
R-22 vapor line diameters and lengths are typically specified for a: - ✔✔Vapor pressure drop
that does not exceed 6 - 7 psi or 6°F.
The primary purpose of using flux when soldering copper or brass parts is to: - ✔✔Prevent
oxidation.
The water that results from a defrost cycle of an air to air heat pump (runoff) must: - ✔✔Drain
off and away from the outdoor coil to prevent excessive ice can build up on the bottom of the
coil and reduce capacity.
The component used to reduce sound transmission and prevent water leaks of a packaged heat
pump installed on a roof is: - ✔✔The curb gasket.
On some installations, a heat pump indoor coil can be installed on an existing, operable, fossil
fuel furnace. When this type of installation is done you need to add a control so that: - ✔✔The
furnace and heat pump do not operate at the same time in normal heating.
When under a deep vacuum, a hermetic refrigeration compressor's motor windings could be: -
✔✔Damaged if energized.
In order for an evacuation to be considered complete: - ✔✔A heat pump refrigerant circuit
should be evacuated to a vacuum pressure of 500 microns or below.
A system is supplied from the factory with charge for a: - ✔✔15 foot line set.
The data plate shows the required system charge to be 5 pounds 10 ounces. - ✔✔The line set
uses a 3/8 inch liquid line and is 25 feet long.
, The manufacturer's instruction sheet specifies 0.6 ounces of refrigerant to be added for each
added foot of refrigerant line length so: - ✔✔The total refrigerant charge for the system would
be 6 pounds.
Drive slips are typically installed on the: - ✔✔Shorter sides of rectangular duct.
To properly set a heat anticipator it is necessary to: - ✔✔Check the heating control circuit
amperage draw.
A heat pump operating in normal ice free conditions maintains a certain temperature
difference between the outdoor coil temperature and the surrounding outdoor ambient: -
✔✔This temperature difference is referred to as coil TD.
The smallest refrigerant leak that an electronic leak detector should be capable of sensing is: -
✔✔0.05 oz. per year.
When checking the pressures in an operating system with a manifold gauge set: -
✔✔Refrigerant oil in a hose will have no effect on the gauge reading.
At sea level, a gauge pressure of 35 psig is equal to an: - ✔✔Absolute pressure of 49.7 psia.
A technician measures the return air temperature of a 100,000 Btu output furnace to be 65°F
and the supply side air temperature is 135°F: - ✔✔The CFM would be 1323.
A residential supply diffuser that is noisy because of a loose vane is best serviced by: -
✔✔Replacing the diffuser.
When performing preventive maintenance on a heat pump the technician should check the
outdoor fan to be certain that the: - ✔✔Fan runs freely with no binding.