Heat pump system
The present disclosure relates to a heat pump system comprising an outdoor unit disposed in an outdoor space, a plurality of thermal load units supplied with cool air and hot air, and an intermediate unit disposed between the outdoor unit and the plurality of thermal load units, wherein the intermediate unit is connected to the outdoor unit through refrigerant pipes and connected to the plurality of thermal load units through thermal medium pipes.
1. A heat pump system comprising
an outdoor unit disposed in an outdoor space, the outdoor unit comprising a four-way valve and an outdoor heat exchanger;
a plurality of thermal load units supplied with cool air and hot air; and
an intermediate unit disposed between the outdoor unit and the plurality of thermal load units,
wherein the intermediate unit is connected to the outdoor unit through refrigerant pipes through which a refrigerant passes, and connected to the plurality of thermal load units through thermal medium pipes through which a thermal medium passes, and
wherein the refrigerant pipes comprise:
a first refrigerant pipe to guide the refrigerant from the four-way valve to the outdoor heat exchanger,
a second refrigerant pipe to guide the refrigerant from the four-way valve to a heating heat exchanger,
a third refrigerant pipe to connect the first refrigerant pipe and the second refrigerant pipe, and
an on-off valve disposed on the third refrigerant pipe to allow the refrigerant to selectively flow through the third refrigerant pipe.
2. The heat pump system according to claim 1 , wherein:
the outdoor unit further includes a compressor to compress the refrigerant,
the outdoor heat exchanger is configured to allow the refrigerant to heat-exchange with outdoor air,
the four-way valve is configured to guide the refrigerant discharged from the compressor to any one of the outdoor heat exchanger and the intermediate unit, and
the outdoor unit further includes an outdoor expansion valve to decompress and expand the refrigerant.
3. The heat pump system according to claim 2 , wherein:
the intermediate unit further includes a cooling heat exchanger to exchange heat between the thermal medium transferred from a first one of the thermal load units and the refrigerant,
the intermediate unit further includes the heating heat exchanger, the heating heat exchanger configured to exchange heat between the thermal medium transferred from a second one of the thermal load units and the refrigerant, and
the intermediate unit further includes an intermediate expansion valve to decompress and expand the refrigerant.
4. The heat pump system according to claim 3 , further comprising
a fourth refrigerant pipe to guide the refrigerant discharged from the compressor to the four-way valve,
a fifth refrigerant pipe to guide the refrigerant from the four-way valve to a suction side of the compressor,
a sixth refrigerant pipe to guide the refrigerant from the cooling heat exchanger to the suction side of the compressor, and
a seventh refrigerant pipe connected to the outdoor heat exchanger and branched into two pieces such that one of the two pieces forms a cooling refrigerant pipe connected to the cooling heat exchanger and the other forms a heating refrigerant pipe connected to the heating heat exchanger.
5. The heat pump system according to claim 3 , further comprising
a fourth refrigerant pipe to guide the refrigerant from the cooling heat exchanger to a suction side of the compressor,
a pressure sensor to detect a pressure at a refrigerant outlet side of the cooling heat exchanger, and
a refrigerant flow rate regulating valve disposed on the fourth refrigerant pipe and whose opening degree is controlled such that a pressure detected by the pressure sensor becomes a value within a set range.
6. The heat pump system according to claim 3 , further comprising
a fourth refrigerant pipe to guide the refrigerant from the cooling heat exchanger to a suction side of the compressor,
a cooling temperature sensor to detect a temperature of the thermal medium cooled through the cooling heat exchanger,
a refrigerant bypass pipe branched from a cooling refrigerant pipe and connected to the fourth refrigerant pipe, and
a bypass expansion valve disposed on the refrigerant bypass pipe to open a flow passage of the refrigerant bypass pipe when a temperature of the thermal medium detected by the cooling temperature sensor is lower than a set threshold value.
7. The heat pump system according to claim 3 , further comprising:
a defrost bypass pipe having one end connected to the second refrigerant pipe and another end connecting a suction side of the compressor to a fourth refrigerant pipe, and
a refrigerant passage switching valve disposed on the defrost bypass pipe to open a flow passage of the defrost bypass pipe when defrosting is required by the outdoor heat exchanger.
8. The heat pump system according to claim 3 , further comprising:
a cooling thermal medium supply pipe to supply the thermal medium cooled in the cooling heat exchanger to the first thermal load unit,
a cooling thermal medium recovery pipe to transfer the thermal medium, which has passed through the first thermal load unit and absorbed heat, to the cooling heat exchanger,
a heating thermal medium supply pipe to supply the thermal medium cooled in the heating heat exchanger to the second thermal load unit, and
a heating thermal medium recovery pipe to transfer the thermal medium, which has passed through the second thermal load unit and radiated heat, to the heating heat exchanger.
9. The heat pump system according to claim 8 , further comprising:
a cooling pump disposed on the cooling thermal medium recovery pipe, and
a heating pump disposed on the heating thermal medium recovery pipe.
10. The heat pump system according to claim 8 , further comprising:
a cooling thermal medium bypass pipe having one end connected to the cooling thermal medium supply pipe and another end connected to the cooling thermal medium recovery pipe,
a heating thermal medium bypass pipe having one end connected to the heating thermal medium supply pipe and another end connected to the heating thermal medium recovery pipe,
a cooling thermal medium bypass valve disposed on the cooling thermal medium bypass pipe to open and close a flow passage of the cooling thermal medium bypass pipe, and
a heating thermal medium bypass valve disposed on the heating thermal medium bypass pipe to open and close a flow passage of the heating thermal medium bypass pipe.
11. The heat pump system according to claim 8 , further comprising:
a first connection bypass pipe having one end connected to the heating thermal medium supply pipe and another end connected to the cooling thermal medium recovery pipe,
a second connection bypass pipe having one end connected to the cooling thermal medium supply pipe and another end connected to the heating thermal medium recovery pipe,
a first connection bypass valve disposed on the first connection bypass pipe to open and close a flow passage of the first connection bypass pipe, and
a second connection bypass valve disposed on the second connection bypass pipe to open and close a flow passage of the second connection bypass pipe.
12. The heat pump system according to claim 8 , further comprising:
a cooling thermal medium supply valve disposed on the cooling thermal medium supply pipe to regulate an amount of thermal medium supplied to the first thermal load unit,
a cooling thermal medium recovery valve disposed on the cooling thermal medium recovery pipe to regulate an amount of thermal medium recovered from the first thermal load unit,
a heating thermal medium supply valve disposed on the heating thermal medium supply pipe to regulate an amount of thermal medium supplied to the second thermal load unit, and
a heating thermal medium recovery valve disposed on the heating thermal medium recovery pipe to regulate an amount of thermal medium recovered from the second thermal load unit.
13. The heat pump system according to claim 4 , further comprising:
a heating refrigerant temperature sensor disposed at a refrigerant outlet side of the heating heat exchanger to detect a temperature of the refrigerant,
a heating refrigerant pressure sensor disposed at the refrigerant outlet side of the heating heat exchanger to detect a pressure of the refrigerant, and
a refrigerant flow rate regulating valve disposed on the sixth refrigerant pipe and whose opening degree is regulated according to a supercooling degree of the refrigerant outlet side of the heating heat exchanger.