Water Leak Detector Recommendations - Adjustable Volume and Easy to Silence
You might be over-engineering this. Modern code demands a cutoff switch in the pan and this doesn't rely on your tenants being there (or paying attention). You just suddenly discover that the HVAC unit is off and the thermostat is dead. The names vary between &quot;HVAC float switch&quot; and &quot;air conditioner moisture overflow switch&quot;, but the idea is you put them in the pan and they kill the AC to prevent water damage. If you have a condensate pump, the modern ones have this switch built-in.