IES-VE User Forum

Hello!

I am new working with IES so I sometimes I have some questions that may look basic but I need them to be clarified. Please excuse me if my questions are too silly.

I am trying to get the heat losses and heat gains before deciding the type of system my building requires. For that. I built the model and I assigned a construction template that I created.

After that, I used the default thermal template with some modifications. I included air exchanges by infiltration and set "none" as system for HVAC (including Auxiliary vent and DHW system). I didn't add occupation as I haven't get that information yet

In the tabular room data I changed the temperature in each room (as they will be different) for heating and cooling.

Finally I ran Apache CIBSE Loads and I got my report.

It is the valid one or should I set a system with 0kW?

It is the way you usually work with IES?

Thanks!

Hi,

The VE own't calculate loads if there is no system present in a room I'm afraid. You need to define a nominal system and set points in order for the loads calculation to find the heat balance and then calculate a load on the room to maintain the conditions.

You should also be careful to make your system air conditioned on the cooling tab if you want a cooling load calculated.

If you don't have system details then you'll have to enter nominal efficiencies, this own't affect room loads but if you look at building or system level loads and energy consumptions then delivery and heat/cool source eff will affect your results.

There are no silly questions but thanks for using the forums and allowing others to offer their own views and see the discussions. Would be interested to know what others do for early stage loads calcs esp re the occupancy - is it better to have some prediction entered here of the number of people and a standard gain from CIBSE/ASHRAE tables for the function of the rooms so this can contribute to calculated loads?

Phil