In the houses from the early part of the last century the kitchens have a chimney in the ceiling for ventilation. It is a simple four cornered five inch deep indentation. Im sure most of you have seen them at one time or another. A while back a company was selling retrofit electric exhaust fans. It was a square flat piece of steel with a fan and grid in the middle that mounted on the opening and connected to electrical lines that you had to run in the attic. Does anyone know if anyone still makes these retrofit exhaust fans or who the company is or was that made them?