Invalid unitary system control zone: air loop unitary HP air to air

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Hi,

I'm modeling a unitary air to air HP, supplied with LTHP Rad. I'm getting the following error in Design Builder whe n simulating. Any idea how to overcome it?

Building 1 - Invalid unitary system control zone: Air Loop Unitary HP AirToAir
Building 1 - Error in HVAC definition

Thanks