Question

In: Mechanical Engineering

A heat pump-bases HVAC system can remove heat from a building by (a) compressing the refrigerant...

A heat pump-bases HVAC system can remove heat from a building by

(a) compressing the refrigerant to make it hotter than the outside air

(b) compressing the refrigerant to make it cooler than the outside air

(c) expanding the refrigerant to make it hotter than the outside air

(d) blowing the heat out of the building using a fan

Solutions

Expert Solution

The correct answer is the option (A).

EXPLANATION

HVAC System based Heat Pump consists of a Vapour Compression Refrigeration cycle, and hence last two options (c) & (d) gets eliminated.

Now for removing heat from a building, that is, for cooling purpose refrigerant need to take heat from inside air and exchange it with outside air so that heat from inside air is extracted and gets transferred to outside air.

Now to transfer heat through the heat exchanger to outside air, the temperature of refrigerant need to me more than the temperature of outside air and hence option (A) is the correct answer.

Do Ask for any doubt and don't forget to give your important feedback so as to improve answering.ThankYou!


Related Solutions

Refrigerant 134a is the working fluid in a vapor-compression heat pump system with a heating capacity...
Refrigerant 134a is the working fluid in a vapor-compression heat pump system with a heating capacity of 60,000 Btu/h. The condenser operates at 180 lbf/in.2, and the evaporator temperature is 0°F. The refrigerant is a saturated vapor at the evaporator exit and a liquid at 110°F at the condenser exit. Pressure drops in the flows through the evaporator and condenser are negligible. The compression process is adiabatic, and the temperature at the compressor exit is 180°F. Determine (a) the mass...
purpose of the condenser in a refrigeration system? a) rejects heat from refrigerant b)absorbs heat into...
purpose of the condenser in a refrigeration system? a) rejects heat from refrigerant b)absorbs heat into the refrigerant c) rejects heat from the condensing medium d) increases pressureand temp of the refrigerant
Refrigerant-134a enters the condenser of a residential heat pump at 900 kPa and 65oC at a...
Refrigerant-134a enters the condenser of a residential heat pump at 900 kPa and 65oC at a rate of 0.018 kg/s and leaves at 750 kPa subcooled by 2oC. The refrigerant enters the compressor at 200 kPa superheated by 3oC. Determine (a) the isentropic efficiency of the compressor in decimal (up to two decimals), (b) the rate of heat supplied to the heated room, and (c) the COP of the heat pump. Also determine (d) the COP if this heat pump...
There is a heat pump that operates with R 134ª refrigerant, whose compressor has a power...
There is a heat pump that operates with R 134ª refrigerant, whose compressor has a power of 5 kW. The heat pump condenser is used to heat oil from a temperature of 0 degrees Celsius, up to a temperature of 20 ° C, so the condenser operates with a condensation temperature of 40 ° C. Furthermore, the evaporator operating with an evaporation temperature of 5 ° C, it is desired to use to air conditioning from a temperature of 35...
Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kW to...
Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kW to heat a dwelling on a day when the outside temperature is below freezing. Saturated vapor enters the compressor at 2.1 bar, and saturated liquid exits the condenser, which operates at 8 bar. Determine for an isentropic compressor efficiency of 75%: (a) the refrigerant mass flow rate, in kg/s. (b) the magnitude of the compressor power, in kW. (c) the coefficient of performance.
what factors affect heat measurement for a buildings HVAC system
what factors affect heat measurement for a buildings HVAC system
For an ideal vapor-compression heat pump cycle, refrigerant 134a is used to provide 35 kW of...
For an ideal vapor-compression heat pump cycle, refrigerant 134a is used to provide 35 kW of heat to a building. Saturated vapor enters the compressor at 1.6 bar and saturated liquid exits the condenser which operates at 8 bar. What is (a) the mass flow rate of the refrigerant, and (b) the COP?
1. When recovery/recycling equipment is used to remove refrigerant from a mobile A/C system, how much...
1. When recovery/recycling equipment is used to remove refrigerant from a mobile A/C system, how much lubricant will be removed during operation? A. 4 ounces B. Generally, very lttle, if any C. The complete system lubricant charge D. At least 6 ounces 2. Which SAE standard(s) must be referred to on the label of approved HFC-134a refrigerant recycling machines? A. SAE J1988 or SAE J1627 B. SAE J1989 or SAE J2791 C. SAE J1990 or SAE J2297 D. SAE J2210...
Design an HVAC system for an office building. All of the offices should be maintained at...
Design an HVAC system for an office building. All of the offices should be maintained at 72°F. Model a corner office, 6m by 6m and 2m high. Make the exterior walls glass and the interior walls are drywall at the ambient temperature. Model a cold winter day as -5°C with a 10 m/s wind and a hot summer day at 40°C with a 4 m/s wind. Model a person as a 37°C vertical cylinder with 1 m2 surface area 170...
An R-134 heat pump system obtains heat from a geothermal source and transfers 90,000 Btu/hr to...
An R-134 heat pump system obtains heat from a geothermal source and transfers 90,000 Btu/hr to an office building for space heating. The refrigeration cycle operates at pressure limits of 50 and 120 psia. If the compressor efficiency is 75%, find the power input (in hp and in Watts). (b) Find the COP for this heating application. If the building used electrical resistive heating rather than a heat pump, how much electrical power (in W) would be required? What is...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT