We live in coastal NH in a close to net zero home , R40 walls, R60 ceiling, heat pump , HRV, ducted system with a wall unit in the basement floor, approx. 1640 sq. Feet on two floors. Our heat pump system crashed last week, condenser in outside unit died, system is 4 years old. Ground array and roof top solar panels more than supply our energy needs, getting an EV soon. So while waiting for the heat pump repair we are trying to use ceiling fans and our HRV sytem and window blinds to keep our indoor temperature in the bearable range. My wife insists on running our ceiling fans at medium to high speed all day and night with the HRV set at 20. With no heat pump function to cool incoming air we are pre-warming our fresh air, this makes no sense to me , we submit the case to experts, what is the best way to run our system until the heat pump is repaired. Thanks for

While running ceiling fans may make you feel cooler, they generate heat and warm the living space. Less so with the modern efficient ceiling fans that only operate on a couple watts, but still true. So only run ceiling fans when you are actually sitting under them.

HRVs don't change the temp of living space very much when it is hot or cold outside. So you won't get much cooling effect from a HRV...just your required and adequate ventilation when operating at its normal speed which is important in your tightly sealed home. What you really need is a whole house fan that you can run when the outside temp is significantly below the desired indoor temp during the night with some windows open. Then turn off whole house fan and close windows as outdoor temp approaches your desired indoor temp. If you have enough interior thermal mass and your humidity level is fairly low, you may find you don't even need AC.

Above 95 degrees fans can actually make you hotter....

https://www.wqad.com/article/news/local/drone/8-in-the-air/when-its-this-hot-fans-actually-make-your-body-hotter/526-1218b36b-bf94-470a-8f30-2c5655476d22#:~:text=Fans%20in%20windows%20can%20blow,can%20actually%20make%20you%20hotter!

I'm in upstate NY. I checked the temps for NH and found them about the same as mine. We don't have central air. We open the windows at night and close them in the morning. Your house is better insulated than mine, it should work.