IES-VE User Forum

Dear all,
I'm having some serious problem trying to define a precise value for auxiliary for a "normal" simulation (not NCM compliace!). Summarizing I have 3 contributions from auxiliary:

- Mechanical ventilation fan power: SFP based on ventilation flow rate (l/s mq)
- Inside unit fan power: SFP based on space heating/cooling load
Equivalent to equation n° 8 of NCM procedure!
- Pumps: fixed value, AEV type (W/mq)

It's not clear if it is possible to make this kind of approach and how. If I assign a single system, fan-coil type in ApacheSys, I can use the SPFs and AEV option to set Mechanical ventilation and pumps power but I cannot assign a room level SFP (for fancoil units). Besides it is not clear how the power consumption is calculate if I put a specific SFP (consumption based on air changes or based on loads?).

Thank you,

Sorry for the double post but I cannot solve the problem. If a define a "zone-level SFP" in a classic apache calculation, at room level I cannot assign any kind of power consumption!




If a switch to VECompliance, same system:



How is it possible?

I think this is a limitation in IES. Under air conditioned systems I think you can only apply an AEV and associated activation profile. If you set the NCM system type to radiators, the room level option opens back up.

I'm not sure how to set around this to be honest. You just will need to keep adjusting the AEV and system profiles until you get a total aux energy value that looks about right. It's either that or go swimming in the murky waters of HVAC I'm afraid.