What is superheating of refrigerant vapour? What are it's causes?

 What is superheating?

Ans: When the refrigerant in evaporator after absorbing latent heat change its phase into vapour and when it travels to compressor through suction line, the refrigerant absorb sensible heat and thus its temperature increases from saturated to superheated condition.

Causes of "Superheating":

Ans: The refrigerant vapor absorb heat in many ways:

1. When it travels through suction line, due to temp difference with the atmosphere, the refrigerant absorb sensible heat from the atmosphere, thus its temp increases.

2. The refrigeant vapor absorbs heat from compressor body.

3. The refrigerant through suction line cools the motor winding thus absorbing heat from the motor.

4. Lastly, the compressor compress the vapor giving abnormal rise in pressure and temperature.

These are causes for superheating of vapor.