A New Diagnostic Tool Enters the Market from a Familiar Manufacturer

The Energy Conservatory has released a new version of its Minneapolis Blower Door, the tool contractors and energy auditors use to measure how much air leaks out of a house (a test that produces a number called ACH50, showing how tight or leaky your home is). The new Model 5 is now open for preorder, replacing a design that had been on the market for decades.

The main changes are practical rather than dramatic. The Model 5 fan weighs about 19 pounds, or 21.5 pounds with an optional battery, compared to 37 pounds for the older Model 3 setup. It also builds more of the test equipment into the fan itself, including a flow gauge that measures airflow, and it communicates wirelessly with the pressure-reading gauge instead of relying on a tangle of hoses and wires. That should make setup faster and testing simpler for whoever runs the blower door in your home.

None of this changes what a blower-door test tells you or what it costs. If you're getting an energy audit or a weatherization job (work to seal air leaks and add insulation) done on your house, this is the kind of equipment that might show up in a technician's kit going forward. It doesn't affect rebate programs, eligibility rules, or the results you'd get from a test — it just means the tool doing the measuring has gotten lighter and easier to use.