Boiler inlet temperature doesn't drop as expected
.jpeg "GSirotti")
Hi, I am a beginner with e+ and OS. I would like to ask you for some advice on a project I am completing with OS. I am trying to simulate an HVAC system served only by two pipe fan coils. I modelled the system as suggested in this discussion (Here) and it seems to work during the summer, but I have some problems during the heating period.
First of all, I attach the layout of the system and would like to ask if it is correct not to define an air loop. I have only assigned FourPipeFanCoil units for each thermal zone and then connected them to the chilled and hot water loop, so without defining a dedicated air loop for each unit (fan coils do not have a dedicated air loop).
Then I would like to ask why, if I graph the inlet/outlet temperature of the boiler, I have these results.
It seems to me that the temperature does not drop as I would expect, and I do not know why in summer it does not drop accordingly with the shutdown of the system (I forced the plant off with availability scheduled off manager). In general, the model simulates less gas consumption than the real one and I think that this could be the problem.
EDIT:
I m going to attach a more readable graph of temperatures and water flow rate through the boiler
.jpeg "GSirotti")
@GSirotti can you create a plot that has three lines:
Perhaps the boiler is shut off in the summer, so flow rate is 0 but temperatures are still constant from the last timestep where the boiler operated (spring).
Hi Aaron, thanks for your reply. I've edited the question with two new graphs where you can see the mass flow rate through the boiler. As you can see the temperature is constant at 75°C during summer and whenever the plant is shut down, as I have scheduled the setpoint of outlet hot water at 75°C. Then during standard working days, it is strange that the temperature drop is really small (about 74°C at the inlet and 75°C at the outlet), I have several fan coils and I expect a bigger drop in temperature.