Customer Reviews

What Does a TXV Do?

A TXV kit is designed to increase the efficiency of your cooling system, and who does not like more efficiency! TXV stands for Thermostatic Expansion Valve. Why do I need a TXV you might ask? Well let us first figure out what a piston does on a refrigerant line. The piston is a refrigerant metering device that the line set will attach to. The refrigerant liquid will pass through the small orifice with a fixed size in the piston.AC-Coil-Piston Pistons can also be used on heat pumps where refrigerant can reverse in directions Piston-Flow The volume of refrigerant and thus the net cooling effect is determined largely by the outdoor unit head pressure which fluctuates up and down based mostly on outdoor ambient temperatures. This can effect the efficincy of the system negatively. This is where a TXV comes in! What Does a TXV Do? A TXV has the ability to sense the refrigerant temperature in the line as it leaves the evaporator coil. For example, if it is cold outside and the refrigerant temperature coming out of the evaporator coil is cooler than the desired temperature it will open to a larger diameter to allow more refrigerant flow in order to meet the heating demands. If its hot outside and you need to be cooler it will also open to a larger diameter to meet cooling demands and once it gets close to the desired temperatures, then it will close back down to a smaller diameter so that you are not losing efficiency. TXV In the picture above you can see the gray tube (power element, capillary tube, and bulb) is what senses the temperature from the indoor refrigerant. This connects to the top, right above the diaphragm and can heat up that bell-shaped space which then pushes the diaphragm down. The spring under the pushpin constantly exerts force under the pushpin to keep it in place. The thin part in the pushpin is actually an opening and as the push pin slides up and down it will adjust the amount of refrigerant that it lets through. I hope this helps clear up any question you have about a TXV.
March 1, 2019
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