Reminders of when to change filters etc

If you are like me, it is quite common to forget when to change smoke alarm battery(10 year), clean the condenser on the dryer(yupp every 6 month), filter on the hvac (every 1 year), clean filter on vacuum cleaner(every 3 months) and so on.

Is there a way to integrate these reminder and reset them in OH when you have done it? Was thinking of cron rules, switches, email notifications and persitance. But maybe there is a better way?

Thinking while I am writing, …

For each reminder do the following:

  • A switch item
  • A rule that creates a timer (for the reminder interval) when the switch changes to OFF
  • When the rule expires, set the switch to ON
  • A rule that sends a notification (email, or whatever) when the switch changes to ON
  • Then when you have done then necessary maintenance (e.g. replaced the filter) you acknowledge the repair by manually flipping the switch (to OFF) and the whole process repeats.

Could this work for you?

That was my idea as well.
Maybe add persistence in case the rpi goes down…

Has anyone done something similar like this before?

Kind regards
Kim SkĂĄtun
+47 950 53 328
Kristofer Jansons Vei 35
5089 Bergen

Hmm… I missed that point. Unfortunately persistence is not going to help with running timers, meaning that the proposed solution will only work as long as your system is running continously. Back to the drawing board…

Given that the maintenance interval is rather large (months, or even years?), it is probably more than good enough to check once a day if it is time to do maintenance.

So, my revised proposal would be something like this:

  • Create a number item (that is initialized to the number of days until maintenance) and a switch item (that is initalized to OFF) for each reminder.
  • Create a rule that fires once a day (based on a cron trigger).
  • In the rule count down all of your number items and check if they reach zero. If zero, then set the switch to ON.
  • Then a rule like above that triggers on switch ON and sends notification.
  • And a rule that triggers on switch OFF (acknowlegde maintenance done) and resets the number (counter) to the value of the reminder interval.

With this approach you can add persistence and thus keep your reminders running across reboots of your system.

Could you use the GCal binding ( and add your reminders into there. Almost certainly far easier (and tbh you could just use the calendar for these reminders :smile:)

1 Like

I looked into that binding aswell as the CalDAV. binding. However I have some problem with the item and rules file:
Item File

Item Switch HVACFilterChange

and then the event item in the google calender:

send HVACFilterChange ON

then the rule file:

rule "Changing hvacFilter"
when Item HVACFilterChange changed from ON to OFF
readd the calender item with event for 1 year ahead of time

And here is my problem, how do I readd the the calendar item for 1 year ahead

Any ideas?

Maybe it is beside the point, but why do you need/want to “read the calendar item 1 year ahead”?

I guess your calendar entry would be a “recurring event”, right? Obviously you will not have any feedback to the calendar to indicate when you did the service/maintenance so your next service interval would not be able to take that into account.

Given that the service intervals are quite long (months to year), however, and assuming that you are “obeying the sevice notice within reasonable time”, this should not matter, or?

In most cases yes, but for the dryer the service interval is 3 month. So if
you live in Norway and have 4 weeks of summer holiday, it would be nice to
shift the recurrent event by 4 weeks.

A side note but you are begging for spam putting all the info up here - might be worth editing that out :slight_smile:

Thanks, replied to the thread on my phone by email when I was on the tram…

I just thought I would update this post, I am currently using IFFTT to trigger a switch item on regular intervals, and that works fine:


Switch item=Ventilation_Filter label="Changing of filter in HVAC" icon="fan" mappings=[ON="CHANGE REQUIRED", OFF="OK"]
Switch item=Drain_Shower label="Cleaning shower drain" icon="fan" mappings=[ON="CLEANING REQUIRED", OFF="OK"]


Switch Ventilation_Filter (Group_Alarms,Group_Ventilation)
Switch Drain_Shower (Group_Alarms,Group_Bathroom)

However it would be nice to display number of days left to change the filter instead of OK, any ideas how this can be done?