Building a Flow and Return Temperature (F.A.R.T. ) Sensor for your boiler using ESPHome

[@richarddalling913]

I have been using two Dallas 18b20 and esp home and esp8266 for the last year to measure the flow and return because the boiler kept tripping and I used node red to check if it should be on and send an alarm if the temp was not above a set value, I also have one on the water cylinder to check the water temp

[@tomasmcguinness]

Tripping? As in electrically?

[@patrickd9551]

@@tomasmcguinness I can't speak for richard, but I used to have a boiler that kept "tripping". Basically the heat exchanger was plugged. The boiler would supply 15-20kw to the heat exchanger, but because it was plugged, the cold water remained cold and the boiler detected an overtemp condition and shutdown, until it was cooled down enough, started back up and tripped again. Easy (but fairly expensive) fix was to replace the plugged exchanger, mainly because half the boiler needed to be ripped apart to change out that simple component.

[@nkachur]

I used the digital sensors with a 15 cm length of pipe insulation tie wrapped over the sensor and pipe. The readings seem almost instant and are within 0.2 degrees celcius compared to my infrared temp gun.

[@tomasmcguinness]

I found that using an IR gun or FLIR on copper pipe gave an inaccurate reading. When I looked into why, I discovered it has to do with the emissivity of copper. I’m at the point now where the NTC matches the professional tool, but even the position of the sensor on the pipe alters the reading. The closer to the radiator, the lower the reading!

[@SimonBennett-c7f]

I would 100% buy this, save the effort of doing it all myself :D

[@alhubo]

Awesome video, thank you for putting it up.

[@tomasmcguinness]

Appreciate that! Glad you enjoyed it!

[@SmithyScotland]

You can buy the actual ds18b20 sensor chip without the metal tube and wiring. Contact area would be about 5mm square. For testing the sensors i use an icepack and a cup of tea. Especially useful when trying to identify muktiple sensors

[@tomasmcguinness]

I tried one of those and found the reading to off. I thought that might be because it’s hot on one side and cold on the other. I think thermal paste and conductive tape would help, but never got around to trying that!

[@allthingsrenewable9017]

It's not a problem. It was interesting to watch.

[@raymondknappJr]

What change would you need to get a Fahrenheit temp?

[@tomasmcguinness]

You could just do the standard conversation : (C *9/5) + 32 where X is the Celsius temperature.

[@geraldkrause8840]

Help. There is something i am probably not doing correctly but just cannot see what it is. Have vscode installed. Esphome installed. I have pasted your yaml file and saved but when i try and compile it, it just comes back with an error as follows. esphome: INFO ESPHome 2023.12.5 INFO Reading configuration .\test... ERROR Error while reading config: Invalid YAML syntax: while parsing a block mapping in "", line 1, column 1 did not find expected key in "", line 2, column 2 Everything is exactly as you have written. I have even written it all out line by line. Here is the first 5 lines of your code as it is in my file. esphome: name: 'boiler-fart-sensor' platformio_options: board_build.flash_mode: dio board_build.mcu: esp32c3 There is something i am overlooking which is probably blatantly obvious. It's driving me mad. Retired electrical engineer who can make things but not good at programming.

[@tomasmcguinness]

Looks like a problem with the YAML. Can you copy and paste it into this validator codebeautify.org/yaml-validator and see what it says. This should give you a better idea where it’s wrong.

[@geraldkrause8840]

@@tomasmcguinness Cut and pasted into the yaml -validator and it comes back with valid Yaml. vs code Seems to not like the first two lines as it says invalid Yaml Syntax and refers to line 1 column 1 and line 2 column 2 Is it anything to do with the name of the file being different to name: boiler-sensor on line 2 not being the same as the file name or does that not matter? Have i not got Vs code setup correctly? Everything looks the same as yours. Below is what i get back as an error when i try and compile it. PS D:\Home assistant\ESPhome> esphome compile .\boilersensor.yaml INFO ESPHome 2023.12.5 INFO Reading configuration .\boilersensor.yaml... ERROR Error while reading config: Invalid YAML syntax: while parsing a block mapping in "", line 1, column 1 did not find expected key in "", line 2, column 2 PS D:\Home assistant\ESPhome> I will persist to get this working. Then i will have learnt something.

[@tomasmcguinness]

I’ve not seen that. Perhaps there is an invisible character or the wrong character set selected? Could you try pasting into Notepad and then back into VSCode?

[@kenbone4535]

I was lost in the first 30 seconds😅

[@tomasmcguinness]

Sorry! It’s the first kinda tutorial I’ve done, so getting the pace and level right will take me some time!!!