After moisture penetration is controlled as best as possible the next approach to reducing attic moisture is by controlling air infiltration.
Attic moisture fan.
Simply by sealing the various possible paths of air leakage already discussed infiltration will be reduced therefore restricting the movement of air and eliminating the stack effect.
How is an attic fan controlled.
An attic fan pulls hot air out of the space and draws in cooler air from outside.
The ideal way to control the operation of an attic fan is with a thermostat and a humidistat.
The whole house fan is installed inside the attic between the living space and ceiling.
A powered attic ventilator has a different purpose.
In summer the thermostat operates the fan when the attic temperature reaches a preset level usually 90 to 95 degrees f.
By adding moisture to the lower floor you increase the partial pressure of the water vapor which pushes it to areas of lower vapor pressure like the attic.
It helps to cool your home temperatures and the attic by approximately 30 degrees.
The warm air escapes through the attic and to the attic vents allowing the circulation of chilly air from the windows.
The whole house fan and the attic venting fan.
If you raise the attic temperature the rh in both places would be the same.
The short answer to this very involved question and the pages of temperature and humidity level data you sent is yes there is a risk that moisture from humid air in your attic will condense on.
Humidity settings are another issue that can make or break the performance of your heating and cooling systems and your attic ventilation.
The difference in the two spaces is the dry bulb temperature.
It is designed to lower the temperature of an attic by exhausting air from the attic and replacing attic air.
In winter the humidistat operates the attic fan when the relative humidity exceeds a preset.
An attic fan works by exchanging the hot air in your attic space for fresh air pulled through the vents.
Unlike a ventilation fan a whole house fan an attic mounted fan that exhausts air from a home at night is designed to cool a house that is to lower the indoor temperature.
Two main types of attic fan there are two devices commonly called attic fans.
An attic fan changes the air regularly so moisture doesn t get a chance to settle and do damage.
This will help to avoid premature damage to the shingles or mold building up in moist hot.
Whole house fans work on the principle of removing the hot and humid air out of the house.