[hacknewslogin]

Is this a good time to ask about a project I would like to do?

I have two 220v heaters in my garage, one on each floor. I'd like to turn one or both of them on from my phone. I'd also love temp sensors near each of them.

So far I haven't found a good FOSS option to control a 220v 40A relay. Any suggestions what to use or how to set it up would appreciated.

[francis_t_catte]

Use something like an Aube RC840T-240; it generates an isolated 24vac supply and has an isolated normally-open 24vac input for closing the contactor. Using anything else is liable to cause life-threatening spiciness if something goes wrong.

I use one for my addition's electric baseboard heat, and control it with a standard dry contact thermostat, but you could easily use a mosfet or relay controlled by an ESP32 or similar instead.

[holgerschurig]

Some completele unrelated nitpick: you wrote "220v".

As a rule of thumb: any physical unit derived from a real persons name is not written in lower case. In this case, the unit honors https://en.wikipedia.org/wiki/Alessandro_Volta and so it's written "220 V" instead.

Applies to other units based on surnames, like Heinrich Hertz' "Hz", Lord Kelvin's "K", James Watt's "W", André-Marie_Ampère's "A" and so on.

[jasiek]

Use a solid state relay with esphome.

https://en.wikipedia.org/wiki/Solid-state_relay

[darknavi]

How do you control the heaters now? Can you use a 5/12v control wire?

[hacknewslogin]

Manually. There's a dial to turn it on, from low to high. One option I considered was a IoT motor of some kind to turn the knob for me.

[alright2565]

Solid state relay is probably a bad idea with all the extra heat-sinking, extra cost, and chance of getting counterfeits.

I do this with ESPHome & a J115F21C12VDCS.9 relay (note only the NO side is rated for 40A resistive): https://i.imgur.com/MqqOkoY.png

Choose any of the temperature sensors here for air temperature sensing: https://esphome.io/

Configuration is so easy. For the sensor, just copy the config from here, for example: https://esphome.io/components/sensor/bme280. Add a gpio output (https://esphome.io/components/output/gpio) and a bang-bang climate controller (https://esphome.io/components/climate/bang_bang.html)

Here's the kicad footprint for that relay (Relay_SPDT_CIT-J115F2.kicad_mod) if you need it:

    (module Relay_SPDT_CIT-J115F2 (layer F.Cu) (tedit 611825E5)
      (descr https://www.citrelay.com/Catalog%20Pages/RelayCatalog/J115F2.pdf)
      (tags "Relay CIT J115F2 SPDT")
      (fp_text reference REF** (at 12.1666 -15.2) (layer F.SilkS)
        (effects (font (size 1 1) (thickness 0.15)))
      )
      (fp_text value Relay_SPDT_CIT-J115F2 (at 18.542 13.9 180) (layer F.Fab)
        (effects (font (size 1 1) (thickness 0.15)))
      )
      (fp_line (start -3.2 -14.1) (end 27.08 -14.1) (layer F.Fab) (width 0.1))
      (fp_line (start -3.96 -13.34) (end -3.96 11.94) (layer F.Fab) (width 0.1))
      (fp_line (start 27.84 -13.34) (end 27.84 11.94) (layer F.Fab) (width 0.1))
      (fp_line (start -3.2 12.7) (end 27.08 12.7) (layer F.Fab) (width 0.1))
      (fp_line (start -4.3 -14.3) (end 28.09 -14.3) (layer F.CrtYd) (width 0.05))
      (fp_line (start -4.3 -14.3) (end -4.3 12.95) (layer F.CrtYd) (width 0.05))
      (fp_line (start 28.09 -14.3) (end 28.09 12.95) (layer F.CrtYd) (width 0.05))
      (fp_line (start -4.3 12.95) (end 28.09 12.95) (layer F.CrtYd) (width 0.05))
      (fp_line (start 17.74 1.778) (end 19.304 1.778) (layer F.SilkS) (width 0.12))
      (fp_line (start 23.876 1.778) (end 25.34 1.778) (layer F.SilkS) (width 0.12))
      (fp_line (start 25.34 1.778) (end 25.34 6.604) (layer F.SilkS) (width 0.12))
      (fp_line (start 21.59 -8.9) (end 17.526 -8.9) (layer F.SilkS) (width 0.12))
      (fp_line (start 21.59 -2.54) (end 21.59 -8.9) (layer F.SilkS) (width 0.12))
      (fp_line (start 21.59 -2.54) (end 22.8092 2.032) (layer F.SilkS) (width 0.12))
      (fp_line (start 17.74 6.604) (end 17.74 1.778) (layer F.SilkS) (width 0.12))
      (fp_line (start 22.86 1.778) (end 23.876 1.016) (layer F.SilkS) (width 0.12))
      (fp_line (start 23.876 2.54) (end 22.86 1.778) (layer F.SilkS) (width 0.12))
      (fp_line (start 20.32 1.778) (end 19.304 1.016) (layer F.SilkS) (width 0.12))
      (fp_line (start 19.304 2.54) (end 20.32 1.778) (layer F.SilkS) (width 0.12))
      (fp_line (start 23.876 2.54) (end 23.876 1.016) (layer F.SilkS) (width 0.12))
      (fp_line (start 19.304 1.016) (end 19.304 2.54) (layer F.SilkS) (width 0.12))
      (fp_circle (center 21.59 -2.54) (end 21.59 -2.413) (layer F.SilkS) (width 0.12))
      (fp_line (start 4.064 -5.1054) (end 5.334 -5.1054) (layer F.SilkS) (width 0.12))
      (fp_line (start 5.334 5.1054) (end 4.064 5.1054) (layer F.SilkS) (width 0.12))
      (fp_line (start 5.334002 5.105397) (end 5.334002 1.777997) (layer F.SilkS) (width 0.12))
      (fp_line (start 5.334 -1.778) (end 5.334 -5.1054) (layer F.SilkS) (width 0.12))
      (fp_line (start -3.2 12.81) (end 27.08 12.81) (layer F.SilkS) (width 0.12))
      (fp_line (start 27.95 -13.34) (end 27.95 11.94) (layer F.SilkS) (width 0.12))
      (fp_line (start -4.07 -13.34) (end -4.07 11.94) (layer F.SilkS) (width 0.12))
      (fp_line (start -3.2 -14.21) (end 27.08 -14.21) (layer F.SilkS) (width 0.12))
      (fp_arc (start 27.08 -13.34) (end 27.84 -13.34) (angle -90) (layer F.Fab) (width 0.1))
      (fp_arc (start 27.08 11.94) (end 27.08 12.7) (angle -90) (layer F.Fab) (width 0.1))
      (fp_arc (start -3.2 11.94) (end -3.96 11.94) (angle -90) (layer F.Fab) (width 0.1))
      (fp_arc (start -3.2 -13.34) (end -3.2 -14.1) (angle -90) (layer F.Fab) (width 0.1))
      (fp_arc (start 5.334001 -0.381001) (end 5.842 -0.762001) (angle -286.3) (layer F.SilkS) (width 0.12))
      (fp_arc (start 5.334002 0.380998) (end 5.842001 -0.000002) (angle -286.3) (layer F.SilkS) (width 0.12))
      (fp_arc (start 5.334 -1.143) (end 5.334 -1.778) (angle -233.1) (layer F.SilkS) (width 0.12))
      (fp_arc (start 5.334002 1.142997) (end 5.334002 1.777997) (angle 233.1) (layer F.SilkS) (width 0.12))
      (fp_text user %R (at 12.3952 0) (layer F.Fab)
        (effects (font (size 1 1) (thickness 0.15)))
      )
      (fp_arc (start -3.2 -13.34) (end -3.2 -14.21) (angle -90) (layer F.SilkS) (width 0.12))
      (fp_arc (start -3.2 11.94) (end -4.07 11.94) (angle -90) (layer F.SilkS) (width 0.12))
      (fp_arc (start 27.08 -13.34) (end 27.95 -13.34) (angle -90) (layer F.SilkS) (width 0.12))
      (fp_arc (start 27.08 11.94) (end 27.08 12.81) (angle -90) (layer F.SilkS) (width 0.12))
      (pad A2 thru_hole circle (at 2.54 5.1 180) (size 2 2) (drill 1.1) (layers *.Cu *.Mask))
      (pad 14 thru_hole circle (at 17.74 8.9 180) (size 4 4) (drill 2.1) (layers *.Cu *.Mask))
      (pad 12 thru_hole circle (at 25.34 8.9 180) (size 4 4) (drill 2.1) (layers *.Cu *.Mask))
      (pad 11 thru_hole circle (at 15.2 -8.9 180) (size 4 4) (drill 2.1) (layers *.Cu *.Mask))
      (pad A1 thru_hole roundrect (at 2.54 -5.1 180) (size 2 2) (drill 1.1) (layers *.Cu *.Mask) (roundrect_rratio 0.25))
      (model ${KISYS3DMOD}/Relay_THT.3dshapes/Relay_SPDT_RAYEX-L90S.wrl
        (at (xyz 0 0 0))
        (scale (xyz 1 1 1))
        (rotate (xyz 0 0 0))
      )
    )

[hacknewslogin]

Thanks! I'll give it a shot.