Bulex eBus temperature too low, heating room slow

Yesterday I installed a wireless tado thermostat paired with thermostatic valves on each of my radiators (12 in total). The boiler is a Bulex and it's connected via eBus. The mode is set to D07.

Before tado, when using the thermostat of Bulex itself, if it was 20c in the room and we set it to 21c, the boiler would turn on and the temperature shown on the boiler was about 50-60c (this is the water temperature to cycle trough the system). The room was at temperature within 10 minutes but with a larger overshoot in the end going to 22-23c.

With tado, 20c in the room and set to 21c on the thermostat, the boiler only shows a temperature of 25c. Tado shows 1 of the 3 heating squiggles which is I assume low heating need. I get that heating the water less might save energy but this way it takes so much longer for the room to reach it's temperature (well over 30 minutes) and in some cases it just doesn't. Boiler putting 25c in the system for the heaters not getting warm at all (long circuit running trough the garage and not that well insulated house).


Is there a way to "fix" this slow or insufficient behavior?

Can I increase the temperature levels related to each heating request levels?

Can I allow a lager overshoot but heat quicker?

Should I ditch eBus and switch to an on/off regime?

Are there other things I might not have thought about?

Answers

  • johnnyp78
    johnnyp78 ✭✭✭
    This is a very late reply but sounds like Tado is working as it should and modulating your boiler’s output. It should learn over time that it needs a higher output level in order to reach the target temperature. You could also ask Tado support to increase the boiler’s maximum flow temperature but bear in mind that condensing boilers only work efficiently if the return flow temp is below 55C.
  • Same problem with my bulex heating system. Room temperature 16,5 requested 22 degrees… tado modulates the heating system to 21 degrees??? Of course i will never reach the 22 degrees. After contacting helpdesk they changed the parameter of the PID configuration in one room… but that is bullshit. There should be a way to control the heating curve like any other modulating thermostat does…will give it 2 more days and then will dismantle everything and send it back to tado. I am a professional installer and have never seen anything like this. Too much control in the cloud….