Underfloor heating with PID controller, Node-RED

Updated 2024-11-14 !

In a former post I did some hacking/checking how our underfloor heating control system handled the valves, actuators, regulating the heat. 

Now it was time to do some tests with Node-RED(NR), with a PID controller, and a Shelly 1(S1) connected via WiFi and driving the actuator.

The actuators are in my case controlled by 24 VAC and the S1 accepts 110 - 240 VAC, 24 - 60 VDC and 12 VDC. So in this case it was simple to just add a rectifier and a capacitor, to the 24 VAC, to get approx 36 VDC to source the S1.

Matter bridge, with Shelly, or non Matter devices

Matter is a smart home standard currently being developed by a consortium of over two hundred companies, including big players such as Apple, Google, Phillips, Amazon and Samsung.

Many new devices have Matter implemented, from the beginning, but devices, such as most of Shelly devices don't. On the other hand many hubs can be upgraded to Matter support. For example an Apple TV.

With a Matter bridge you can solve the incompability. This post will use Matter bridge plugin Manager and the Shelly plugin but it could be other devices shown in the picture below.

CTC heatpump MODBUS interface

Updated 2024-11-14 !

The installation of a CTC heat pump(HP), EcoAir 600, and the indoor module, Eco Zenith i360, was not optimal from the beginning, so to monitor it closely I checked how to retrieve data. 

The newer CTC HP:s are always shipped with a MODBUS TCP interface, without any additional hardware, which solved the issue.

MODBUS was new to me but after some reading and checking I found that there is a NodeRed node which solves the interface dialog.

MODBUS RTU gateway, WiFi, Ethernet, WEB server

In my project to get data from the Swegon Casa HRV, FTX, i needed a new solution to distribute the MODBUS data from the CASA.

The thing is that I have a Raspberry Pi(RPi) that is the central HUB for everything going on in our house, but away from the CASA, and the data is there vizualized in a NodeRed dashboard.

Since the CASA RTU is serial, using Waveshare USB to RS 485, and I didn't want to install a new long cabel to the central RPi I used another RPi which is near the CASA.

Shelly devices as "native" Apple HomeKit accessories

Updated 2024-11-09

I have been using Shelly devices for quite some time both on our boat, off grid, and also as HomeKit (HK) accessories via Homebridge (HB). 

I was really amazed when I found that some smart guys have created a software package that replaces the stock, official, Shelly firmware with the "Shelly-HomeKit" package which emulates a "native" Apple HomeKit accessory.

It's very nice done, really simple, and the flashing of the software is done over the air (OTA) with your ordinary WEB-browser.

Node-Red quick install

Updated 2024-11-06 !

Node-Red(NR) is Flow-based programming for the Internet of Things

This post isn't made as a complete install guide, there are several, just some links to the best information I have found.

The best thing is that even if you don't are a skilled programmer, but like logic flows, you can make really advanced things. It's pre-installed on some Raspberry Pi(RPi) distributions.

Running Node-Red with multiple instances ?

Swegon CASA, HRV (FTX), rotary heat exchanger and MODBUS

Fresh air at home is very important ! For more than 15 years ago, at a major renovation of our house, we installed an HRV or in Swedish FTX system. Since then there have been nice updates for FTX equipment so when one of the fans was a little noicy and when the motor for the rotor died it was time to do an upgrade instead of repairing the old one. So we purchased an CASA R7 Genius(R7).

For me its important to get as much data as possible, to optimize energy consumption in our house, so despite that the the R7 have a nice app we also added a SEM interface to get the data, via MODBUS, that is available.