Hello guys, is there anyone know how to set the supply flow rate to a constant like(1500cfm)? I am using DOE prototype HPSF building, the fan they used is "on/off"; the air terminal unit is single duct, constant, noreheat. However, all the setting here relevant with supply air flow rate is "maximum supply flow", only can help me to bound the upper, but still not a constant.

So, I use a VAV air terminal instead, set the max and min of supply air flow which didn't work; I also change the supply air flow in "Air Loop HVAC: Unitary Heat Pump air to air" which didn't work; I also try to change the supply air in "coil" which didn't work. I even create setpoint manger, or reset in api, but no one works.

I plot the supply air and supply temperature, I found supply temperature is like a constant, 12±0.5; and supply flow jumped. But in my real case, I have a constant fan and variable temperature.

I was wondering if anyone could give me some directions?

Best

and all air flow setting is "maximum supply flow"

And I want to reset the supply flow rate to 1500cfm()