Effect of B.F on A/C system :

As a result of BF, the room sensible heat and latent heat (room total heat) go up due to the addition of sensible and heat of the bypassed fresh air. This means that, the system has to remove a larger quantity of heat due to B.F.

a) Effect Of Smaller BF :

1. Requires higher ADP ( Apparatus Dew Point )

2. Requires less air, this reduces the size of the fan and motor.

3. Provides more heat transfer area.

4. Smaller piping as less chilled water is sufficient.

b) Effect Of Larger BF :

1. Requires lower ADP. This means lower refrigerant temperature at evaporator. Size and Capacity requirement of refrigeration plant is increased.

2. Requires more air - larger fan and motor required.

3. Less heat Transfer area.

4. Larger Piping is required because of more chilling water requirement.

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Mechinopedia For Mechanical Engineers

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