The factors that you would need to take account of in determining the surface temperature of a................

Question

what factors that you would need to take account of in determining the surface temperature of a cooling coil in an air handling unit??

Answer 1

For the heat transfer conditions on the outside of the coil you would need to know the Maximum and Minimum properties for the inlet and outlet air streams i.e. Dry Bulb, Wet Bulb temperatures, and dew point if necessary, and the operating atmospheric pressure.
You would also need to specify a maximum and minimum inlet or outlet air flow in SCFM, of CFM.

For the heat transfer conditions on the inside of the coil you would need to know the heating or cooling medium and its properties, and the flow rates of the circulating medium.

From these conditions, and using your knowledge of heat transfer and psychometrics and thermodynamics, you could calculate the temperature of the coil, or you could ask the coil manufacturer to do the calculations for you and tell you what the coil temps would be for the various conditions, which is what I would do.

Answer 2

from a design perspective you would need to consider the duty required from the coil, is it cooling only or will you be using it for dehumidification also? then its simply a case of calculating the maximum air temperature that will be passed over it, the volume of air to be cooled (m3/s) and the relative humidity (if dehumidifieing). when designing, design for worse than the worst case or expect the maintenance engineers to swear at you for the next decade.

Answer 3

The surface temperature of the coil will be the temperature at which you have the thermostat set. (That's where the thermostat gets its refrigeration control signal from).

Answer 4

Use an infra red thermal method;It's non contact so cannot influence the coil.It would also show any regions whose temperature is very different to the rest.

Answer 5

You can work out temperature by it's colour.

If you could create a temperature/colour chart, you could work it out that way

Answer 6

why would you want to. that's what you pay other people to find out.