Trane trg-trc005-en User Manual

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TRG-TRC005-EN
33
period four
Expansion Devices
notes
A typical recommended superheat setting is from 8 to 12°F [4.4 to 6.7°C].
Too little superheat is risky because it presents a danger of allowing refrigerant 
to leave the evaporator in the liquid state. As mentioned earlier, the compressor 
is designed to compress vapor, not liquid. Liquid refrigerant can cause damage 
to the compressor.
Too much superheat dedicates too much of the tube surface to the production 
of superheat, reducing system efficiency. In extreme cases, it can lead to coil 
frosting; it may also cause the compressor to overheat, possibly shortening its 
service life.
Superheat Setting
I
Too little superheat:
K
Risk of damage to compressor by liquid refrigerant
I
Too much superheat:
K
Reduction of system efficiency
K
Potential of coil frosting
K
Risk of compressor damage due to overheating
Figure 48