Part L 2A compliance_NCM system_water loop heat pump

[Paduk]

Good afternoon,
I am in the process of assessing a development in terms of Part L2A compliance and I am experiencing the following problem.

The HVAC system is made of a gas fired CHP plus a ground water heat pump and top up gas boilers.
So the way I have created the overall system is as following:

- ground water heat pump (water loop heat pump from the NCM wizard)
- CHP with 0.001 fraction of heated rated output in order to maximize its use
- bivalent system LTHW gas boiler (meeting say 25% of the load)

I have selected the "Water Loop Heat Pump" as, considering also the description given in the Isbem guidance, it seems to be the system the more accurately would match the M&E design however this is creating a massive "auxiliary" spike compared to the Notional building as the Notional building uses variable speed pump and the WLHP uses constant which cannot be modified.

I spoke to the M&E guy who designed the system adn he told me that the WLHP pump will be variable speed so i dont know how to match this in my model. i am thinking about selecting the Fancoil option rathen than WLHP. would this be acceptable?

Any thoughts?

Thanks,