Dean focuses on plumbing and HVAC issues, this time from an installer's perspective, and how to navigate around the issues that pop up when you're dealing with them. Dean also answered listener questions regarding a hard water recirculation problem, mold that keeps returning to the same places in a small master bathroom and how to get rid of it once and for all, whether or not whole house fans are really worth it and do they really save you money on air conditioning, and how to best mitigate noise for a downstairs condo unit when buying the unit upstairs.