The Winter Problem
Older homes have many air leaks around: A/C vents, ceiling fans, light fixtures, ducts, switches, outlets, etc. On windy winter days, turbines such much warmth from rooms through the 12" hole in roof.
The Solution (Low Cost & Quick)
1. Turbine Boss louvers CLOSE in winter.
2. Cuts turbine's Winter Heat Loss by 80%.
3. Saves money every year.