Net Zero HVAC w/ Bill Spohn, Eric Kaiser and Kaleb Saleeby

Bill Spohn joins Eric Kaiser and Kaleb Saleeby at AHR 2022 to talk about his experiences designing and living in a home with NetZero HVAC.

NetZero HVAC refers to system design with tight coordination with the house to make it as efficient as possible. Some of these systems are so tight and efficient that they approach passive house standards (0.6 ACH50). Bill lives in a modular home that also generates more energy than it consumes, and it doesn’t rely on natural gas.

The greatest expenses of Bill’s NetZero home came from all the custom factors, as it didn’t make sense to price many of the features on a square-foot basis. The heating and cooling system is also unique, as it is completely separate from the ventilation system, which is a Build Equinox CERV. On the IAQ side, the CERV monitors outdoor temperature and humidity, indoor CO2, and indoor VOCs. Bill also has a HAVEN central air monitor inside the CERV system as a backup.

Bill’s HVAC system is an air-source heat pump that provides two tons of heating and cooling and has low-temperature capabilities. The two-ton unit works for a 4400-square-foot home.

Bill, Eric, and Kaleb also discuss:

  • Energy independence
  • Controlling radiant heat gains and window construction
  • Construction and material fabrication
  • Monitoring energy usage
  • Energy recovery ventilation (ERVs)
  • Thermal bridging at work in Bill’s walls
  • Knowledgeable customers
  • Jim Bergmann’s help with troubleshooting
  • Radon issues
  • Bill’s podcast
  • Solar inverters
  • Measuring tool accuracy

You can learn more by listening to Bill's podcast, Building HVAC Science. Subscribe to that podcast on any podcast app of your choice or get an overview at

You can also check out Bill’s blog at

If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.

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