Heat Pump ESCO Exam 100 QUESTIONS WITH COMPLETE VERIFIED SOLUTIONS 2024, Exams of Physics

Download Heat Pump ESCO Exam 100 QUESTIONS WITH COMPLETE VERIFIED SOLUTIONS 2024 and more Exams Physics in PDF only on Docsity! Heat Pump ESCO Exam 100 QUESTIONS WITH COMPLETE VERIFIED SOLUTIONS 2024 1. An air-to-air heat pump has many of the same components as an air conditioning system. The major difference is that a heat pump also has a (an); C: reversing valve. 2. What is the difference between "demand defrost" and "timed defrost?" D: demand defrost only happens when needed, and time defrost is on timed temperature 3. The thermostat that controls the auxiliary electric heat according to the outdoor temperature is called the; C: outdoor ambient thermostat. 4. The outdoor temperature at which the heat pump provides the same amount of heat as the heat loss of the conditioned space without auxiliary heat is known as the; A: initial balance point. 5. At what temperature is an outdoor ambient thermostat normally set? B: At or slightly above the initial balance point. 6. The outdoor coil is frozen solid on a "no heat" service call. The most likely reason is: D: outdoor fan is inoperative 7. In order to determine a heat pumps' balance point, you must first calculate; A: the building's heat load. 8. Heat pumps are sized to handle the; A: cooling load. 9. a high efficiency heat pump system designed to function from high or low ambient conditions below 10F may have; C: auxiliary heat exchanger injected with a ethylene glycol solution. 10. Room thermostats for heat pumps should be installed; B: as near to the main return air grill as possible. 11. When the heat pump compressor has malfunetioned, the cus tomer has the option to switch the system into; B: emergency heat mode. 12. Start-up with a night set back digital thermostat requires the technician to always; D: teach the customer to program the thermostat. 13. The heat pump defrost board can be manipulated by the technician to; C: simulate the defrost cycle. 14. The air-to-air heat pump outdoor unit is most efficient if located; C: in a moderate climate zone. 15. Which of the following are innovations that may be found on new high efficiency units? D. ECM motors 16. How may a lockout (impedance) relay be reset? C: Simply disconnect power to the unit momentarily. 17. The temperature difference between the 1t and 2od bulbs for heating on a heat pump thermostat is; C: approximately 2°F 18. SEER calculated by: B. BTUs removed by the watts consumed during the cooling season 19. if the indoor fan is operated at an excessive speed in the coolin mode? A: the system will not properly remove the humidity from the conditioned space. 20. The most preferred method of charging any system in the field is; C: by weight. 21. What is the industry standard for deep vacuum? C: Maintain 500 microns for 15 minutes. 22. Good service practice for installation of a reversing valve includes; D. use heat paste and wet rags while brazing in the new valve 23. off cycle crankcase heat is provided by B. dual run capacitor, which allows a small amount of current to flow through the windings 24. -from this information you can include that; A : airflow in CFM is above normal range 25. What control operates the 1st stage of secondary heat? C: The second heating stage of the indoor thermostat. 26. What is the industry standard for maximum duration for defrost? C: A maximum of 10 minutes. 27. What is the recommended CFM across the evaporator coil of a heat pump? B: 400 to 450 CFM. 28. If manufacturers specifications are not available, a good way to determine cubic feet per minute through a coil is to: A: use temperature rise on emergency heat mode. 29. What type of defrost is employed on this heat pump? B: Time and temperature initiation, time or temperature termination. 30. Which component is responsible for energizing auxiliary heat during the defrost cycle? D: The defrost relay. 31. When this unit switches to the heat mode, describe the sequence of events that take place. 61. Since electric resistance heat provides 1 watt of usable heat for each watt of energy purchased, electric resistance heat has a COP of; A: 1 : 1 62. As outside ambient air temperature decreases, a heat pump's COP; B: decreases. 63. During the defrost cycle, the system switches to the__________________ mode. D: cooling 64. During the heating mode, the refrigerant in the indoor coil is under; B: high pressure 65. What three things happen on most air-to-air heat pumps during defrost? C: The reversing valve must switch to cooling mode, the outdoor fan shuts off and auxiliary heat is energized. 66. High suetion pressure and low discharge pressure on a heat pump system can be an indication of; C: compressor inefficiency 67. The PREFERRED method to perform adjustments to the refrigerant charge in a heat pump system is in the________mode. B: cooling 68. You answer a service call for insufficient heat. You find the suction pressure is higher and discharge pressure is lower than normal. Using a digital thermometer, you measure the line entering the reversing valve from the compressor discharge and find 215F You then measure the line leaving the reversing valve that connects to the indoor coil and find 185F. These readings are an indication of; B: a faulty reversing valve. 69. The customer complaint is not enough heat. You install service gauges and find low side pressure is higher than normal and the high side pressure is lower than the normal. You switch the system to the cooling mode and find the pressures a re normal. The most likely cause of the problem is; A: a stuck open check valve at the outdoor coil. 70. A customer complains that their heat pump system blows cool air periodically during the heat mode. This could be caused by; A: a faulty defrost relay (does not energize the aux, heat during the defrost mode). 71. When a heat pump is in the heat mode, frost ca n accumulate on the outdoor coil even when the ambient temperature is 45°F because; A: the outdoor coil must be colder than the ambient air 72. The indoor fan on a heat pump system operates; B: at the same speed for heating or cooling. 73. The defrost cyele can be initiated by; C: time and temperature. 74. The defrost eycle can be terminated by; C: time/temperature 75. Movement of the piston in the reversing valve is accomplished by; C: bleeding pressure from one side of the piston to the suction side of the compressor 76. Some close coupled (package unit) heat pumps use an electronic expansion valve to meter refrigerant. One advantage to using an electronic expansion valve is; A: electronic expansion valves can meter refrigerant in either direction 77. Liquid line filter/driers that are used on heat pump systems; D: must be a special bi-flow design if used without check valves. 78. When installing the heat pump outdoor unit, care should be taken to provide for drainage during the____cycle . C: defrost 79. The indoor coil is usually mounted in the air stream__________the auxiliary electric heat strips. A: before 80. On duel fuel systems, the indoor coil must be located; B: after the heat exchanger. 81. Air-to-air heat pumps are most practical to operate in areas where the lowest winter temperature does not go below____________* A:+10 82. The air-to-air heat pump, operating without auxiliary heat, provides air to the registers that is approximately___________°F or less. A: 100 83. The most common method of defrosting the outdoor coil on an air source heat pump is; D: reverse cycle defrost 84. COP is the abbreviation for; A: Coefficient of performance 85. at temperatures, the heat pump refrigeration cycle permits the; A: condenser to release 3 to 4 times more heat than it takes in electrical energy to drive the compressor. 86. In addition to heat from the outdoor coil, a heat pump in the heating mode will get heat from; D: Compression 87. When operating in the heat mode, hot gas leaves the compressor and first flows to; D: the reversing valve. 88. When operating in the cooling mode, hot gas leaves the compressor and first flows to; D: the reversing valve. 89. To make the reversing valve slide move, the system must have a pressure difference of; C: 75 to 100 psig. 90. Before connecting your manifold gauge set to a heat pump system, you should first; D: verify the operating mode of the system. 91. In the heat mode, the suction line entering the compressor contains; C: low pressure/ low temperature vapor. 92. The reversing valve is often referred to as a; C: four-way valve because of the number of connections 93. A heat pump has a thermostatic expansion valve (TEV) and a check valve at each coil. When the modes are reversed; C: refrigerant will bypass the TEV on the coil serving as the condenser. 94. Mechanically troubleshooting a reversing valve can be done by; B: checking the temperature differential between the connection serving the low side 95. A reciprocating heat pump compressor differs from a light duty A/C compressor in that; D: its designed to operate at high compression ratios 96. One of the most important devices to insure the longevity of a heat pump's reciprocating compressor is the; C: crankcase heater 97. A heat pump can be difficult to charge properly because; D: low ambient conditions 98. high efficiency heat pump system charged with 410A refrigerant normally use a; C: txv metering device for the heating and a fixed orafice metering device cooling cycle 99. When a heat pump is operating in the cooling mode, the; C: indoor metering device is metering refrigerant and the outdoor check valve is open. 100. When in the cooling mode, the low pressure refrigerant vapor leaves the reversing valve and travels to the; B: accumulator and then to the compressor