Thermostat task for underfloor heating
Thermostat Task, PID, Underfloor heating:
The Output value is linked to a Binary output actuator (KNX) for simply ON/OFF operation. The Input value is linked to a floor sensor / temp probe input (KNX).
Question is when I increase the setpoint value to a higher value than the input value feedback is returning to the system, the output is not switching ON. However I can manually override the output using bOS Client. What could be wrong?
bOS ver. 4.11.38
Hello,
Have you double checked everything?
I've quickly tested a thermostat, with exactly the same conditions as yours, and it's working.
Please note, that with PWM, the output might not be immediately turned ON / OFF, as the value is basically controlled according to the cycle time, and it has delays, etc. I usually don't mess too much with the values on the PWM, I just choose if it's warm water, electric, etc, because that influences the PWM calculations. I usually don't use bOS thermostats, I use the existing KNX thermostats, but the principle is exactly the same.
When I started using PWM control several years ago, the clients were always confused and calling saying "Why is the valve output turned off right now? Is it not heating?", when basically the PWM turns ON / OFF the valve in a way that tries to mimic a curve, so that the heating / cooling gets there with minimum fluctuation.
Just double check the outputs, turn on the heating, increase your setpoint to the desire level, and pay attention to the output for some time, I'm sure you'll see it turning ON / OFF sooner or later.
Best regards