Dew Point Too High

Questions & AnswersCategory: GeneralDew Point Too High
Guest Staff asked 2 years ago

This is the problem. The dew point of the desiccant heated type dryer was recorded for 2 hours and the pattern indicates the Dew point is too high. Maximum going upto 10.4 Deg Celcius. Minimum at -2.

The cycle of twin tower each is 60 minutes.

What can be the reason for the High dew point. Also the heating cycle is greater than the cooling cycle.

2 Answers
Cas Staff answered 2 years ago


Basically, the problem is that the desiccant isn’t regenerated enough/completely, or it can’t absorb water for some other reason.

How old is the desiccant inside the dryer? Desiccant has a limited lifetime, every xxxx hours it needs to be completely replaced (please check the manual or ask the manufacturer).

It could also be the heater… is it still heating? Without enough heat, the desiccant won’t regenerate completely.

Also, these dryers normally will require an oil-absorbing filter upstream (before) the dryer. This to prevent oil from entering the dryer, which is very bad for the desiccant.

Hope this helps.. let me know how it works out..



Elchin answered 4 months ago

Hi, This is problem. air dew point exceeding design specification on air dryer. both inlet an outlet filters has been changed several times as well as desiccants. But, it didn\’t help Each tower spends 5 minutes in drying mode and 5 minutes in regeneration mode, for a total operating cycle of 10 minutes. What can be the reason for the High dew point. Thanks in advance