Is it something like what roger did?
I hadn’t come across that.
Mine is more at the Boiler end monitoring inflow/outflow temperatures and recording burn time so oil consumption and costs can be calculated. I’ve gone down the Tasmota, Berry, HASPmota route, instead of ESPHome.
If I can, I will also try to do some graphing, and then, possibly, get HA to report what’s going on at the hot water tank, but I’ve no sensors there atm.
Anyone think this method is today valid?
I try the Post #6 solution but i don’t see the variable into the Tasmota Device inside the HA