Ground temperature in energy plus

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Thank you for answering very quickly. I'm not sure this is happening to me. Maybe something is missing from my model or Energy plus is not using Kiva because I have these two warnings that show I've defined Foundation:Kiva but still the ground temperature is 18C. I also checked the Output "Environment:Site Ground Temperature".

• Warning * Foundation:Kiva="KIVA", no Footing Material Name defined * ~~~ * Footing Depth will not be used. * Warning * GetHTSurfaceData: Surfaces with interface to Ground found but no "Ground Temperatures" were input. * ~~~ * Found first in surface=SOUTHGROUNDWALLBASE

Surfaces using the Kiva method need to use "Foundation" as their boundary condition type. "Ground" is reserved for the ground temperature input method.

I changed them to the foundation boundary condition and I realized that the Ground temperature is still 18C but this time (when I'm using the Kiva method) the temperature of my basement is different from the case that I don't define Foundation:Kiva. I was wondering if when I use Kiva I should expect different temperatures for the basement because the heat transfer between the ground and below-grade walls and basement floor are basing calculated with a more accurate method. My problem is still with the ground temperature. It doesn't seem that Kiva is changing the default value (18).

My concern is that this 18 degrees value is still being used in the heat transfer calculations for the energy balance of the basement zone. However, I don't know how can I find data regarding the ground temperature based on the climate zone, depth, and season.

@Melina if you're reviewing the Site Ground Temperature output variable, that is repeating the user-set values of a Site:Ground object. If you're using Kiva, you don't need those objects and should ignore the Site Ground Temperature output variable. You can read more about the limited output variables for Kiva surfaces here.