@skywatch My apologies for derailing the topic, yep, got two of the boiler feed and return also, and tapped into the trigger wire to notify boiler ON/OFF so Domoticz tracks the run time per day.
12 degrees is recommended across the radiator but it's not quite so simple, it also matters WHEN you get that differential -
That's where the portable node came in. Plastic pipe clips held sensors on the inlet and outlet pipes of the rad, the downstairs 6 all had a 11-12c differential at around 16/17 minutes, but no way would the upstairs 3 get there before the boiler cycle ended (room thermostat), which I put down to longer pipe runs.
I increase the rate on the thermo-valve (pressure agnostic) to get the same heat on the return at ca 18 minutes. Rinse/repeat the remaining 2, eh voila. Balanced, a nice little peak on the return flow temperature at the boiler, reduced gas bills and every room +/- 0.5 of it's set point.
Actual differential of these 3 upstairs radiators will be WAY under 12 for a constant feed, but for a heat cycle of 19-25 minutes depending on outside temperature it's perfectly balanced before the cycle ends.
Answering one of my own questions.
On ethernet gateway send() may return true when there is no connected controller, even when there is no ethernet cable plugged in.
@Yveaux Thanks!
Nice graph. I will do something similar in Grafana. I think my MySensors device should also report every minute, perhaps using the highest sampled value. All values are sent to MQTT by my gateway and my Home Automation will store the time value pairs in influxdb. Right now I'm waiting for the hardware to arrive...
