Last summer, I wanted to ensure that my pool pump runs for a minimum of 2 hours per day (which is enough to run all of the water through the sand filter twice).
However, I did not want it to be at fixed times, because I might be starting the pool pump because I'm adding chlorine, or because I am heating the pool, or because I am doing a backwash...
I ended up writing complex rules that would accumulate the runtime of the pump, and then triggering it at the end of the day if it had not run for long enough...
Yesterday, my brother wanted to run his air exchanger fan for a minimum of 15 minutes per hour, but it already starts at various interval if the gas furnace is heating, so he had basically the same problem: running a switch for a minimum of time during an interval, despite the switch being turned on and off independently by other events.
This morning, I decided to write an app for that. It is still in development, but it might be useful for some people, so I am putting it out here. For now it is on Github, but I will add it to HPM once I have used it for a few days.
