Hot floor heating system

Hi, I installed an electric heating floor in my apartment. So I installed one Velbus screen with four temperature sensors , one four relay module and one usb module. Mainly the system runs fine, but when I program the system according an schedule, only one of the sensors changes the function perfectly, the other three are always in the same state.
The schedule is the same for the four sensors, the modules are perfectly detected by the velbus software and the schedules are recorded in the screen module.
Does know somebody what could be happening??
On the other hand, as suggestion, could be great to create an small module that connected individually to each sensor switchs on a load. I constructed one optically isolated based on a triac but I have to connect it to the red led output.

Is there somebody who can help me?
I have four VMB1TS, one VMB4RY with a VMB1TD to control my apartments heating system. I can control everything perfectly with VELBUS software. But only one of the sensors changes according the schedule I stablish. The other three sensors are always in the same position, but can be changed from the VMB1TD.
I don’t know what am I missing.