Temperature Control Tuning - Temperature Setpoint Overshoot

[Gast]

I have some cast iron radiators that continue to heat for 20 or 30 minutes after the actuator shuts off hot water.

This is Causing the room to overshoot the temperature setpoint by 2 or 3 degrees.

Is it possible to tune or configure the control loop to account for this and if so how do i do it?

Thanks.

[TGeissler]

Hello Jimmycooker, how do you control the radiator? I think with loxone!

I assume your radiators are acting with a watherpump with ist also controled by loxone. Your main building block is the intelligent room controller. You have temp sensors connect to it. If its so you don´t need to manual control this senario because the logic in the room controller block do all for you. But the logic must learn how fast is the room at the specivied temp. Give them time to learn.

Or is something different?

Greez Tom

[Gast]

Hi,

Thanks for getting back to me.....

Yes, i have a locone miniserver and tree with touch / touch pure light switches and tree actuators controlling / restricting the flow to my radiators based on the room temperature.

Thats great news about the temperature control block learning overtime.....

Ideally, when heating up from say 17 degrees C to 22 degrees C it will learn that it needs to start restricting / shutting off flow to the radiator when it reaches 20 degrees C (as there is currently a 2 degree overshoot).

Loxone doesn't control my boiler at the moment, I have to turn that on and off using a separate (nest controller) for now.....it is an old non modulatiing (on / off) boiler.

Thanks,
James.

[Gast]

One thing i've just though of......will the block learning be messed up by the fact the temperature setpoints are never reached when the boiler is off?

[TGeissler]

The time to reach the setpint temp is the main think of the room controller. Wenn the temp is not reaching all actuators are at 100%. But when the boiler ist on, he knows that he can reach the def. temp. Now it takes some cycles until he learnd the correct time.

Do you realy need to take the boiler offline?

[Gast]

Yes, so if the boiler is off it is taking infinite time to reach setpoint.....so i assume this will prevent the controller from 'learning' how quickly it takes to heat when the boiler is on?

I cannot leave the boiler on all the time as this is also feeding some older (uncontrolled) radiators.....