It’s really upsetting how this is an enforced aspect of a radon system without any work arounds for Minnesota’s freezing problems. A decent number of homes warrant externally routed systems because of numerous reasons, and I have been installing these on every system ever since I was in the first batch of failing inspections, and I have to explain to the client that “this is probably going to wake up you in the middle of the night, but the department of health is enforcing it, so here’s how you remove the battery when that happens.” This is not well thought out, almost every mitigator I know is up in arms about it, and I agree with David Smith, Andy Costigan, Randy Weestrand, Steve Reichert, and everyone else against it, there are many more issues brought up that haven’t been considered when making this a mandate.