Expansion valves contain a movable rod which travels up and down inside the valve. So how does the expansion valve know how much refrigerant to meter into the evaporator, and how does it do it? First the “how it does it”, and it’s quite simple. This process of varying refrigerant flow based on system cooling demand is referred to as “metering” the refrigerant into the evaporator. ![]() If we were to allow too little refrigerant to enter the evaporator, there may not be enough to properly absorb the interior heat, which would also result in inadequate, or no cooling. This would eventually bring cooling to a halt. This would not allow the hot interior air to pass through its fins, and the refrigerant flowing inside the evaporator would not be able to absorb the heat from the air. For any given operating condition, if we were to allow too much refrigerant to enter the evaporator, it would get too cold, and the moisture collected on it could freeze. ![]() Since system operating conditions vary (sometimes high cooling demand, sometimes low cooling demand) it is necessary to be able to adjust the amount of refrigerant entering the evaporator. Like any other valve, its job is to control flow in this case, the amount of refrigerant entering the evaporator. The expansion valve’s place in the system is at the evaporator inlet.
0 Comments
Leave a Reply. |