Designbuilder - HVAC
Hello everyone!
I am working on my first DesignBuilder model for ASHRAE 90.1/LEED certification. I am running into some issues with the HVAC module not allowing me to exactly replicate the systems currently designed for the project. Specifically:
1) The project HW loop is heated by a fluid HX fed by a district steam system. I can't connect district heating to a HX in the HW loop supply side, and I can't control anything about the district heating itself. I believe I need to include district heating efficiency in my LEED calculation. How do I model this?
2) The project CHW loop is set up to be "geothermal ready" meaning that the water is chilled by a water-source heat pump. Currently, the WSHP is connected to a large rooftop adiabatic cooler rather than the future ground loop. Designbuilder will let me connect the WSHP to a condenser loop but I can't add a dry/adiabatic cooler to the loop - just a cooling tower or fluid cooler. I'm concerned that this will affect accuracy. Is there a way to make this correct?
3) The project has two large rooftop DOAS units with heat recovery. These are essentially ERVs with enthalpy wheels. When I try to configure these DOAS units in DesignBuilder it shows them as though they need additional components connected to the intake and exhaust instead of functioning as they would with intake and exhaust grilles on the unit itself. I can't figure out how to fix this and it's making my whole model fail to simulate! Help would be appreciated.
Finally, I would be so appreciative if someone would be able to look over the whole model and flag egregious errors and omissions. I know that's a big ask but would be happy to discuss terms for that kind of support offline.
Thank you all.
