Hello fellow growers and automation enthusiasts! 
I’m currently working on a Node-RED flow to monitor and control the VPD (Vapor Pressure Deficit) in my grow tent. The goal is to notify me when the VPD goes out of my desired range (±0.1 kPa) for a certain period. While I’ve made some progress, I’m hitting a snag in getting the notifications to work reliably. Let me share what I’ve done so far and where I’m stuck. I’ve set up the flow to read ambient temperature, leaf temperature, and humidity. Based on these readings, it adjusts the humidity to maintain the target VPD range. The flow also includes checks to turn the humidifier on or off based on the current VPD. However, the notification part isn’t functioning as expected. I’ve tried implementing a delay and comparison node to check if the VPD stays out of range for the specified time, but it doesn’t trigger the notification consistently. Here’s a quick overview of the flow structure: - VPD Calculation: Combines temperature and humidity readings to calculate VPD. - Range Check: Compares the current VPD against the target range. - Notification Trigger: Should send a notification if the VPD is out of range for the set duration. I’ve attached the flow details for closer inspection, but I’m not entirely sure where the disconnect is. Is it in the way I’m handling the state checks, or perhaps a miscalculation in the VPD range? Any insights or suggestions would be greatly appreciated! 
On a positive note, I’m amazed at how Node-RED simplifies complex automation tasks. It’s incredibly empowering to tweak and refine flows to suit specific needs. I’m hopeful that with some community input, I can get this VPD notification system up and running smoothly. Looking forward to hearing from you all! Let’s grow together! 