They are 2 different things. A whole house fan will suck cool outside air thru windows or doors in the house into the attic and out whatever attic vents you have, wall or ridge vents. The cool outside air will cool your house. I have one in my main house in the bay area. You can cool certain rooms or areas of the house depending on where you open doors or windows. They work great and don’t cost much to buy or run. Attic fans blow hot air out of the attic but are not designed to cool a house other than by reducing the heat transfer from the attic.
Both will cool the attic but a whole house fan cools the house also.
Then house or attic fan is to remove heat from the attic. When the fans run the theory is to suck or push the hot air out. That’s why you would block certain vents so that it is removing the heat and not competing with other vents. I have seen solar units that install over vents from Costco.
What is the current conventional theory about whole house fans. Whether it’s an attic fan or a whole house fan, I have heard that you need to close off the ridge vents in the roof. What are others finding along along these regards.
We would rather to be able to cool down the house without putting in air conditioning.