Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
EnergyPlus assumes that the heating coil and cooling coil in a PTHP is actually the same coil with a reversing valve - thus it will size the two coils to be the greater of the calculated heating or cooling coil capacities.
The supplemental heating coil will also be sized for the full heating load, because the DX heating coil can be locked out below a certain outdoor air temperature.
It would be nice for EnergyPlus to provide an option to decouple the DX heating and cooling auto-sizing. Even when attached to an airloop, Coil:Heating:DX and Coil:Cooling:DX seemt to have coupled auto-sizing:
(diagram created using EP3)
