Missing Heating Load

[Nicko11]

I am using Apache HVAC for the first time to model a boost ventilation system at external condition (with not heating or cooling coils).

I have created the ventilation system an the apache results confirm that the flowrates etc are working as anticipated. However, the heating system that I have assigned in Apache is now not showing any heating loads to the room set point defined in the room template.

I was expecting Apache would see the additional air from Apache HVAC and adjust the emitter sizing to suit.

Do I also need to model the heating system in Apache HVAC for this to work?

[farahghanem]

Once you have used ApacheHVAC for the simulation, you will need to use it throughout. So yes, you will have to model the heating system in ApacheHVAC.

[Nicko11]

Thanks for the replay farahghanem,

I have now created a heating system in Apache HVAC by importing a prototype system from the templates and then removing the unwanted airside part of the prototype. I have then assigned radiators to the hot water loop for each space, however there still appears to be no heating loads after I have re-run the simulation?

[farahghanem]

I am not sure to what extent you have modified the prototype, but I am assuming you kept at least the space components. It would be better to "turn off" the controllers instead of deleting them so as not to compromise the network if you are new to ApacheHVAC.

After you have assigned the rooms to the space components in the network, and set the radiators, you will need to re-run the room and system sizing before observing any loads.

[Nicko11]

One the prototype is imported I have deleted all the airside system to just leave the hot water loop and heat generator.

I have then assigned radiators to my room and the hot water loop system. The radiators then have an on/off set point controller assigned based on a timed variation with absolute values for occupied temperature 20°C and a set back temperature 12°C. I have then also ticked the box for autosizing assuming that this means the software will determine the size of the radiator.

However, I am unable to run the systems calculation in Apache HVAC as the button is greyed out. I assume this is because some data or one of the systems is set up incorrectly however I have a very basic system and having read the instructions cannot figure where my issue lies?

[macleodd]

I believe the sizing buttons on toolbar would only be greyed out in two scenarios:

- You are in the waterside display mode: simply switch back to airside display
- Your network filename is set to 'UNKNOWN'.

Regards, Donald