one zone HVAC

[andy_vick22]

I am modelling a single thermal zone with heating/ventilation only, and 100% glass (greenhouse). I chose the HVAC system 09h, and assigned the only zone to the 'multiplex'. The component did not seem to update with the zone however - and I thought it had to do with the multiplex. So I de-multiplexed the system, and applied the room in the same way - I'm not sure if the icon of the person at the desk is still supposed to show up? but it didn't.
In any case, after running the full simulation with this HVAC system, the inside temperatures are nowhere near controlled; ranging from 80C to -10C (which you might expect in an all glass room over an annual sim. if there was no control at all). Can anyone suggest how I might have applied the HVAC system to the model incorrectly, or configured the setpoints incorrectly, or a step I might have missed? (I did autosize everything, using the room sizing/system sizing tools). Or is the HVAC system just not good enough to control this situation (which I don't really believe yet..)?
Thanks for any advice.

[geshen516]

you need to set the control schedule correct besides assigning a room to one multiplex.
check "system setpoint and schedule" in equipment sizing session in the help mannual.

another solution without running apachehvac is: set the thermostat setting in room thermal settings.

[andy_vick22]

Thanks for your response - I have tried both of these things, with no luck... I have also tried adding controllers to the HVAC system to tell it to turn on heat when the temperature is too low in the greenhouse, but in all the simulations I'm running, still no heating to speak of! It is following almost exactly the outdoor temperatures.
I can't imagine what could be happening. I have autosized and resized the system over and over, modifying the room thermal template, the setpoints, etc. Any more suggestions?