recording energy usage for SHW in energy+
Hi All, I am modelling my service hot water on the same loop as my heating in energy+ as is the case in the real building. I use the following outputs to try and record how much energy is being used by the service hot water vs the heating system: SHW:WaterSystems:EnergyTransfer J, Water:Facility m3, NaturalGas:Facility J, Heating:NaturalGas J.
Heating:NaturalGas J and NaturalGas:Facility J are always the same so it doesn't seperate out here. Then SHW:WaterSystems:EnergyTransfer J, is different and generally works to measure the SHW portion of the heating system. However in the .idfs I am working on now, the first has a SHW usage of 59 MWh (it's a commerical kitchen). When I change the thermostat setpoints for the heating system from 24/7 26'C to mon-friday 9am to 9pm 22'C with a setback of 6'C, the SHW usage reports as 17 MWh, I haven't changed the SHW at all. I am reporting out using SHW:WaterSystems:EnergyTransfer J. - Does anyone know why this might be the case and whether there is a different variable I can report out in case this one is wrong.
Thanks in advance
If the water heater is acting as a heating device also, the only approach that I can think of is to allocate the energy used by the SWH each time step by the load on the loop from service hot water vs space heating loads. It is possible I'm misunderstanding your question.