What are the assumptions conditions for heating design calcu

What are the assumptions (conditions) for heating design calculation? For cooling design?

Solution

For heating design calculation -

1. The heat exchanger operates under steady-state, steady flow conditions.
2. Heat transfer to the surroundings is negligible.
3. There is a no heat generation in the heat exchanger.
4. The specific heat at constant pressure is constant for each fluid.
5. Longitudinal heat conduction in the fluid and in the wall are negligible.
6. The overall heat transfer coefficient between the fluids is constant throughout the heat exchanger including the case of phase change.

For cooling design -

1. The building occupancy is assumed to be at full length capacity.
2. All building equipment and appliances are considered to be operating at a reasonably reprasentative capacity.
3. Latent as well as sensible loads are considered.
4. The heat transfer due to ventilation is not a load on the building but a load on the system.
5. Assume dynamic coditions.
6. The latent heat gain is assumed to become cooling load instantly, whereas sensible heat gain is partially delayed depending on the characteristics of the conditioned space.