Boiler Loads Unusually Low on Dynamic Simulation

[Gambit_216]

I'm completing a model for a university module and using IES for the first time. I've created the model but there seems to be some odd values for the Dynamic Simulation.

The Apache system suggests that the boiler load should be around 470kW and the CIBSE peak loading suggests around 500kW which seem a little large for the building, it is pretty old and inefficient, but not a million miles away but when I run the Dynamic Simulation and open the graphs the boiler load seems to peak at 112kW and averages at around 50kW-70kW which is too low.

I've double checked all the systems and these seem to be ok and that the correct thermal profiles are assigned to each room but the boiler loading is still very small.

Hopefully someone can help!