Engine

1. An engine comprising:

an engine temperature specifying unit including a timer configured to measure duration of an operation of the engine, the engine temperature specifying unit configured to specify an engine temperature according to the duration measured by the timer; and

a control device configured to control the engine based on the engine temperature specified by the engine temperature specifying unit, wherein, to control the engine, the control device is configured to:

during the operation of the engine, receive a stop signal indicative of an instruction to stop the engine; and

in response to the stop signal, continue the operation of the engine based on a determination, by the control device, that the engine temperature is less than a predetermined temperature, and based on a determination, by the control device, that a degree of superheat of a refrigerant is less than a predetermined amount.

2. The engine according to claim 1 , wherein the engine temperature specifying unit includes a cooling water temperature sensor configured to detect an engine cooling water temperature.

3. The engine according to claim 1 , wherein the degree of the refrigerant is associated with a refrigerant line coupled to a compressor and to an accumulator.

4. The engine according to claim 1 , wherein the control device is further configured to, in response to the stop signal, determine whether the engine temperature is greater than or equal to the predetermined temperature.

5. The engine according to claim 1 , wherein the control device is further configured to, in response to the stop signal, determine whether the degree of superheat of the refrigerant is greater than or equal to the predetermined amount.

6. The engine according to claim 1 , wherein the control device is further configured to, after the stop signal is received by the control device, stop the operation of the engine based on a determination that the degree of superheat of the refrigerant is greater than or equal to the predetermined amount.

7. The engine according to claim 1 , wherein the control device is further configured to, after the stop signal is received by the control device, stop the operation of the engine based on a determination that the engine temperature is greater than or equal to the predetermined amount.

8. The engine according to claim 7 , wherein the control device is further configured to stop the operation of the engine after a pup down operation of a heat pump is performed.

9. The engine according to claim 1 , further comprising a heat pump.

10. The engine according to claim 9 , wherein the heat pump includes a pressure sensor configured to detect a pressure of a refrigerant line and to output, to the control device, a first output signal associated with the pressure.

11. The engine according to claim 10 , wherein the heat pump includes a temperature sensor configured to detect a line temperature associated with the refrigerant line and to output, to the control device, a second output signal associated with the line temperature.

12. The engine according to claim 11 , wherein the control device is further configured to:

determine a saturated steam temperature of the refrigerant line based on the first output signal; and

determine the degree of superheat of the refrigerant based on the saturated steam temperature and based on the second output signal.

13. The engine according to claim 1 , wherein the stop signal comprises a thermo signal that indicates that a room temperature has reached a set temperature.

14. The engine according to claim 1 , further comprising:

an accumulator configured to separate gas refrigerant and mist refrigerant; and

a compressor configured to receive gas refrigerant from the accumulator via a refrigerant line.