We have a very high water table where we live, and sewerage is a septic tank with a second pumping chamber which pumps the tank outflow to the drainage field in the garden. Pump is controlled with a float switch.
Often the GivEnergy portal would show a high house load of 1.2KW in autumn/winter when nothing obvious was switched on. Much head-scratching and I remembered that the tank pump is around 1KW - but why was it coming on so often?
I'm running HA on an RPi and also have an ecowitt weather station. Here's a plot of last weeks house load, and hourly rain rate:
You can see loads of regular spikes on the load graph, corresponding to the pump running, and also see how the spike frequency rises dramatically after heavy rain, then slowly reduces. We realised that rainwater/groundwater is leaking into the pumping chamber, so the pump's working overtime pumping water out, only for much of it to leak back into the tank.
Leaks into the pumping chamber are hopefully being fixed today. The electricity cost saving won't cover the repair costs, but should greatly increase the lifespan of the pump which is an expensive item!
