An energy auditor inspected my home and suggested that I install a ceiling-mounted bathroom exhaust fan designed for continuous use, specifically a variable speed model. They mentioned it should be set to operate at 30 CFM and be left running at all times. I'm having difficulty finding such a fan. Does anyone have any recommendations?
3 Answers
Check out Panasonic's Pick-A-Flow fan! It comes with these insert modules that allow for features like humidity sensing and adjustable CFM settings. There's a WhisperGreen Select module that keeps it running at a constant rate unless you manually switch it on for higher airflow. I had one installed in my new home; it works great!
Having a fan that runs 24/7 can be wasteful, especially if you live in a colder area. Make sure you weigh the costs for energy savings. Plus, is this really necessary for your bathroom? They're primarily for removing moisture, not just for continuous background noise!
You might want to ask the auditor why they suggested a continuous fan. Normally, the ASHRAE ventilation guidelines only require bathrooms to have either a 50 CFM intermittent fan or a 20 CFM continuous fan. Finding a ceiling-mounted fan under 50 CFM might be tricky, unless you're considering a more expensive ERV, which comes with its own maintenance hassles due to filter cleaning.