The default generic backup cooling and heating sources simply allow for a simulation model that always addresses the full load at the coil. Therefore, when the VRF equipment is properly sized to meet cooling and heating loads, these generic backup cooling and heating sources should have zero or insignificant operating time during an annual simulation.
The COP setting is provided so that users may set a value here that will reasonably approximate VRF operation if the backup does come into play (i.e., if the autosized or manually sized system does not quite cover all loads all the time).
A meter selection is provided to facilitate separate tracking of energy used for this virtual backup. Again, if the VRF system is properly sized, the energy used for this backup cooling source should be either zero or insignificant.
