HVAC II Final Exam Review 100% ACCURATE AND UPDATED!

IF a heat pump works normally in the heating mode but will not provide cooling or a defrost mode, which component is most likely defective? - ANSWERReversing valve Air-to-air heat pumps produce heat by - ANSWERextracting heat from the outdoor air and transferring it to the indoor air In addition to the reversing valve, the other major difference between a heat pump and a cooling only system is - ANSWERheat pumps require two metering devices In the cooling mode, the reversing valve is normally - ANSWERenergized When a heat pump is operating in the heating mode, the refrigerant bypasses the - ANSWERindoor coil metering device In the reverse cycle heating mode, - ANSWERthe indoor coil acts as a condenser Refer to figure RQ01. What happens in the cooling mode if the discharge temperature switch fails to close? - ANSWERThe outdoor fan does not run Refer to figure RQ02. If the outdoor thermostat is not closed and this system is in the heating mode, a likely symptom would be - ANSWERless supplemental heat available Refer to figure RQ03. Defrost is initiated by - ANSWERdefrost control Which of the following conditions is not common and proper during the defrost mode? - ANSWERThe compressor shuts off If a heat pump blows cool air into the conditioned space during the colder parts of the heating season, a possible cause is - ANSWERthat the supplemental electric heaters are not on during defrosting