Currently, the CAZ data only shows in the HPXML files. It does not show in the tech specs of the homeowner report.

Using the CAZ fields is optional unless required by your program. They are located in the last section of the input fields, below Health & Safety.

If all of the appliances are in the same room or area of the home - then they can be all included in the same combustion zone. If they are all in the same area - then check all of them to link them together for the zone.

Or you can develop multiple zones. For example, if the HVAC system is in the basement by itself then develop it as a separate zone.

When you click on Add a zone, the remaining unselected combustion appliances will be available in the new zone. Check the appropriate appliances for this new zone.

If you decide that you need to change you zones, or the appliances that are in the zone, uncheck the appliance - and a pop-up will ask you to confirm that you want to delete that appliance from the zone. This action deletes the link to that zone and any data that was entered in the CAZ section for that appliance. It does not delete the appliance from the input screen. (If you accidentally chose the wrong zone for an appliance, you can switch the zone it’s attached to by clicking on the appliance and editing the CAZ field).

After deleting the dryer from zone 2, it shows in both zones as unlinked. You can add zone 3, and it will move down or you can link it to an existing zone.

When you click on the name of the appliances, the data field for that appliance opens. You can open and close these whenever needed.

A note about multiple fuels:

If you have multiple HVAC systems, or hot water systems, be sure to list the combustion equipment first - when filling out the input fields of the report.

For example, if there is a gas furnace, plus an electric heat pump - please list the gas (combustion) system first, so it will show in the CAZ section properly.

If you have a gas water heater plus an electric tankless water heater, please list the gas water heater first on the input fields.

References:

Building America Solution Center
​Combustion Appliance Zone (CAZ) Testing

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