The piston (fixed orifice) and TXV (thermostatic expansion valve) are the two most common metering devices in use today, though some modern systems utilize an electronically-controlled metering device called an EEV (electronic expansion valve). It should be noted that there are other types of fixed-orifice metering devices, like capillary tubes; however, their use is not […]

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Before the fighting starts about term definitions, let's just settle on using “adjustable drive pulley” and “sheave” interchangeably to describe the belt-driven power transmission device shown above. Second, for the newer tech, you shouldn't be altering these sheaves so that the belt rides lower or higher in them unless you know EXACTLY what you are […]