RefrigerationPregunta 61 de 110
On a fixed-orifice (piston) system, which method is generally used to check the charge?
a.Subcooling only
b.The superheat method using target superheat charts
c.Weighing the compressor
d.Measuring duct static pressure
Explicación
Fixed-orifice metering devices are charged by the superheat method, comparing measured superheat to a target based on indoor wet-bulb and outdoor dry-bulb temperatures. TXV systems, by contrast, are typically charged by subcooling. Using the correct method for the metering device is essential.
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