For the future, please see this post for details of how to post flows or code - How to share code or flow json
Are you using MQTT? If so then use a Retained Topic in MQTT for the current value.
Alternatively you can use persistent context for storing values. See Working with context : Node-RED
Have you watched this playlist: Node-RED Essentials. The videos are done by the developers of node-red. They're nice & short and to the point. You will understand a whole lot in about 1 hour. A small investment for a lot of gain.
