Initial setup for very slow system? (Underfloor heating in old brick building)

[freaked1234]

Hey there!

I am living in a massive brick building with underfloor (water) heating that is very slow to react. Could you give me some guidance how to initially setup this thermostat and how to fine tune it over time?

Thank you very much!

[ScratMan]

Hello, if you already have temperature measurements on which you can see the oscillation due to regulation, you may compute the PID gains using the method described here : https://github.com/ScratMan/HASmartThermostat/discussions/21#discussioncomment-1709437

[10bn]

@freaked1234 Did figure this out for yourself and could you may share your settings?

[freaked1234]

@freaked1234 Did figure this out for yourself and could you may share your settings?

Hey, since winter was pretty much over when I wrote this I don't know if my settings work. I'll play around a bit with it when it is getting colder and will let you know.

Maybe we could exchange contact details and work something out together. First we should compare our building specs to see how much difference there is. A throwaway mail of mine is [email protected]

Anyway I'll post my settings as soon as I know they work and I would appreciate if you could do the same!

[T81]

Some useful info would be the temperature of inlet water (if known) and if it is easy to overshoot the setpoint temperature

[T81]

@freaked1234 any updates?

[HermesHonshappo]

Here are the values I have for a room with underfloor heating, using water.

• Kp: 40
• Ki: 0.00075
• Kd: 30000
• Ke: 1.5

Room is insulated basically: sheetrock with 8cm insulation behind, and when the floor was poured, there is 8cm insulation below the floor with the water pipes. But the walls behind the insulation are basic brick, the windows are basic double glass windows (but the cheapest ones in the store), and the ceiling has no insulation yet

The water inlet is regulated to 35°C (I have a mechanical temp controlled mixer & pump purchased from Amazon)

I get regulation I'd say is acceptable:

EDIT: one thing I forgot to add: I have a temp sensor that is in the floor slab. And I'm regulating not by measuring temp in the room, but temp of the floor slab. I found that having the floor slab at 25°C during the day gives an acceptable room temp (between 18 and 19°C), and good comfort