Understanding Evaporative Temperature in Heat Pumps: Explained

[TSN79]

I'm reading a text about heat pumps here which says that if the outside temperature drops, then the evaporative temperature also drops. This confuses me. I thought the evaporative temperature (at a certain pressure) was a quality within the refrigerant? Can someone explain this to me?

 

[russ_watters]

If the temperature outside drops, the temperature of the refrigerant drops, and therefore the pressure also drops.

 

[astrokreng]

I can provide some clarification on the concept of evaporative temperature in heat pumps. The evaporative temperature is indeed a property of the refrigerant, but it is also influenced by external factors such as outside temperature. This is because heat pumps work by transferring heat from a colder area (outside) to a warmer area (inside). As the outside temperature drops, the heat pump has to work harder to maintain the desired temperature inside, and this results in a decrease in the evaporative temperature of the refrigerant. In other words, the refrigerant needs to be colder in order to absorb heat from the colder outside air. It's important to note that the evaporative temperature will still remain within a certain range, as it is determined by the refrigerant's composition and pressure. I hope this helps clarify the relationship between outside temperature and evaporative temperature in heat pumps.