Quote Originally Posted by r.bartlett View Post
The offcoil humidity will be high due to the low off coil temperature. however it has relatively little water content so as soon as it mixes with the room air the room humidity will be low.

to confirm we are still at the design stage here and not actual operating conditions?
Yes, this is the point. The supplied air is almost at 95%RH, as it is with all air conditioning applications. But, the set point is reached, when this air absorbers the heat inside the room as represented as a straight line (between off coil and room conditions). The issue is, I don't have enough loads, for this conditioned air to absorb heat and this causes high Relative Humidity. The specific humidity is obviously low. . . Unfortunaly, its not in design stage, the system is operational. It gives me trouble during off peak period. Summers are good. I am worried about winters and rain, when the building envelop load is also less. . .

See the attached psy chart. Don't bother the calculations, see the SHR, at part loads. scan_00032.jpg