Filter and chemical reminders? Need help with timers

I have a couple of basic dashboard switches for our hot tub to remind about filters and chemicals. I want them to turn on after x number of days. The hitch is that I'd REALLY like the timer to reset when the switch is turned off. This will allow me to check during that time window and easily double tap on a dashboard if I see fit. I'm checking through RM and don't see what I THINK I need.

I have seen some apps in HPM for timers but they all seem geared towards several hours type scenarios not days or weeks.

Why not use a rule with a hub variable, then increment the variable by +1 each day using a periodic trigger. Then, if your variable is equal to or greater than your target time, run your notification (turn switch ON)?. Turning off the switch could trigger a separate rule that resets the variable to zero.

1 Like

There is a way you can do this with RM and DateTime variables. You can set a variable to some date and time plus an offset, or the current date and time plus an offset. The offset is in minutes, but can come from a variable. So, to set a variable to 15 days in the future, some variable math would yield that as 1440 * 15, or 21600. And, DateTime variables can be triggers of rules.

And as @dylan.c suggests, you can use Periodic to trigger something every so often. But right now there is not a simple way to recalculate the period used in that. Whereas, with Certain Time trigger and DateTime variables, you can recalculate as needed.


So simple! I like this one because then I could easily modify the target number to reach before trigger

I think this will work out very well! Thank you for the guidance.


Then I'm using notifications to make Echo announcements and send notifications to our phone. I have the notification for switch on wait for 1 minute so the desired feature of cycling the switch to reset won't cause a notification.

1 Like

Do you use an electronic calendar such as Google Calendar? I do realize that it depends on an Internet connection to the Cloud, but it works for me.

I regenerate my water softener every 10 days. I get a reminder via Gmail and on my Alexa devices the night before. I set up an event to repeat every 10 days.
Likewise, I check my HVAC filter on the 20th of each month; Google reminds me. I set up an event to repeat on the 20th day of each month.