Central floor heating - Brand to buy?

New here. My old Wirsbo/Uponor system is dead (C-55 control unit). And I need a new system including new thermostats in all rooms.

Is there anything that is supported to some degree that would allow me to make more intelligent floor heating (in concrete).

Brands easily available is:
Danfoss Smartlink / One. Cloud based app. Closed source. PWM control. No PID for floor heating.
Uponor Smatrix. expensive control box available supposedly with HTTP, Modbus etc.
Wavin AHC 9000

What kind of wiring do you have?

As an example I had whole floor heating system from Roth. Kind of a dummy system where all room thermostats were “standalone”. Meaning that one thermostat controlling one valve without any central intelligence. Now I have Produal 0-10v (Temp + humidity or temp + pontentiometer) sensors wired to multiple Siemens Logos and one S7-1200. Valve actuators are 230v and those logos are 230rc by type. Rooms where sensors with potentiometer is used I have ±2 degrees temp adjustment. All this is connected to OH with modbus.

Is there anything that is supported to some degree that would allow me to make more intelligent floor heating (in concrete).

With this kind of system you can have anykind of intelligence you want. Programmed in logos or OH. Or maybe a bit of both.

Now I have a dead Uponor system (old type).
10 wireless thermostats, and 10pcs 24V Actuators on central heating.
I have one manual (turn around) thermostat on the forward feeding water temperature.

So I have unscrewed the actuators a bit to get some continous flow, and using the forward water temp to control house temp by feeling.

Danfoss will control my 24V Actuators, so will a new Uponor system, and likely a Wavin system as well. Roth is also available and also seems to use 24V actuators.

Like the idea of Uponor having self balancing, prediction, PWM and the option of a local interface box. Danfoss has some prediction and PWM. Wavin seems to be modbus to some degree, but it stupid on/off, and not complete reverse engineered.

If I can integrate it, I will try some predictions based on weather forecasts. Uponor seems to be the smartest system out of the box.

If you want some kind of “smart” system, controme does it, including weather forecast. It comes with another backbox server (i.e. rasbperry), and as we are in openhab forum here, I suppose you want to get done something by yourself? With controme you will rather have no (technical) influence besides the iphone/android app which they provide.

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If I can get a system I can hook up to, and adjust the temp of the individual rooms, I want the system to perform its job in reaching the target temp as efficient as it can. If it has a “keep floor warm” option, that does a 2% PWM cycle that is nice.

What I want is look at weather forecast myself, if there is predicted high sun from the morning, I want to turn off the system if not home, as the sun will heat some rooms to 26+C even at -5C. But I also knows, that as the sun settles, I will lose energy faster than the floor heating can react (4-6 hours), so I will want to run the floor heating in some rooms at an increasing PWM rate before it gets cold the have an energy influx in the flow that will have effect when sun is gone.

Many systems just runs 100% until temp (on the way up) hits thermostat temp setting. Then turns off, and temp continues up, for an hours or more, floor gets cold and at some point when floor is very cold it turns on again. Danfoss/Uponor tries to make predictions and run PWM - That is run heating on/off in shorter pulses to eliminate the large temp span. Danfoss says they have no PID except on quick react radiator thermostats.

This can be done by myself even on a partially intelligent system by adjusting target temp up/down say every minute. Not sure if I will kill the system in days or weeks, if I keep writing new values to NVRAM. An STM32F1 flash will last 10k write cycles, EEPROM 100k cycles.

So a change once per minute for 7 days, and I have passed 10k cycles in a little over 2 months. Or maybe I need my own thermostats (DHT-22 + ESP8266 ?) as some systems does not store value of thermostats in nvram but wait until a new sigfnal is sent before it knows temp and target of a termostat. It all depends on the code in the centra device.

But it should be doable to create something with a PID loop - even if it works 4-6 hours delayed, and overlay target with external temp curves/expected internal temp curves.

I’m not so into the different systems, but as far as I know, the “chepo” Moehlenhoff-2 system has a simple XML interface that more or less all homeautomation can connect to. But it only does on/off setpoint stuff.

I lately came across the Eltako Series 14 (I’m looking for an alternative to my crappy HMW). Beside any of the usual actors, they also have heating actors (FAE14LPR) which do PWM on the temperature diff. to the setpoint. The series 14 stuff communicates over rs485 bus and connects to Openhab AFAIK. It also has a bridge to Eltako Enocean 868Mhz, and I have some of those running with OH (homegear), which works perfectly.

Hey Povl,

Did you end up with a new system and what did you go with?

Hi Poul,

I’m in almost same situation. Need to decide on central floor heating system and need to secure easy integration into OH2 for changing setpoints and monitor temperatures.
Options seems many (Danfoss, Roth, Upenor, Wavin, Pettinaroli, Salus, Megatherm, …), but i don’t find anyone of them having a binding made already.

What did you end up choosing and maybe you can share your experiences :-)?