Compression heat pump, in particular for applications near households

Abstract

A system for household-related heat recovery from waste water includes a compression heat pump having a compressor for a coolant, a condenser, and an evaporator. Disposed between the condenser and the evaporator is an expansion valve, and a temperature probe is arranged on the evaporator at a location at which coolant is injected. A switching valve switches over a flow resistance of the expansion valve between two fixed flow resistance values. Below a predetermined temperature at the temperature sensor, the switching valve switches over to low flow resistance of the expansion valve and above the predetermined temperature, the switching device switches to a higher flow resistance of the expansion valve.

1 - 6 . (canceled) 
     
     
         7 . A system for household-related heat recovery from waste water, comprising:
 a compression heat pump having a compressor for a coolant; a condenser; an evaporator, and an expansion valve disposed between the condenser and the evaporator;   a temperature probe arranged on the evaporator at a location at which coolant is injected; and   a switching valve for switching over a flow resistance of the expansion valve between two fixed flow resistance values, said switching valve switching over to a first flow resistance below a predetermined temperature at the temperature probe and switching over to a second flow resistance of the expansion valve above the predetermined temperature, said second flow resistance being higher than the first flow resistance.   
     
     
         8 . The system of  claim 7 , wherein the expansion valve is formed by two throttles with fixed flow resistance that are selected via the switching valve. 
     
     
         9 . The system of  claim 8 , wherein the switching valve is embodied as a switchover valve and switches between the two throttles with different flow resistance. 
     
     
         10 . The system of  claim 8 , wherein the two throttles are connected in parallel to one another, said switching valve being embodied as a closing valve and disposed in a flow branch of one of the two throttles. 
     
     
         11 . The system of  claim 8 , wherein the two throttles are connected behind one another, said switching valve being embodied as a closing valve and disposed as bypass in parallel to one of the two throttles. 
     
     
         12 . The system of  claim 7 , further comprising a control electronics constructed to detect and evaluate a temperature and to actuate the switching valve.