How it works

GrowRig is a few small parts that each do one job. You don’t have to understand all of them to use it, but a quick mental model makes setup and troubleshooting much easier.

The parts

Part	In plain terms
Grow App	The screen you actually use — dashboards, setup, alerts, and history.
Grow Core	The brain. It knows your targets and decides what the equipment should do.
Grow Hub	The small computer in your home that runs everything (Home Assistant + Grow Core).
Grow Gateway	The network that keeps your grow devices on their own safe Wi‑Fi. (Optional at first.)
Grow Controller	A small board near the tent that drives fans and reads sensors, with safe local fallback.
Sensors & equipment	Your thermometer/hygrometer, fans, light, and plugs.

Home Assistant sits quietly underneath, handling the “plumbing” of talking to all those different devices. GrowRig adds the grow-specific brain on top so you think in terms of tents, targets, and roles — not entity IDs and wiring.

The big picture

Here’s how a command flows from you down to a fan:

You → Grow App → Grow Core → Home Assistant → Grow Controller → your fan

…and readings flow back up the same path, so the app always shows what’s really happening.

The control loop

At its heart, GrowRig repeats one simple idea, over and over:

What's happening now   (e.g. it's 28 °C)
        compared to
What you asked for      (target: 24 °C)
        decides
What the equipment does (speed the exhaust fan up)

This is called reconciliation. If the tent drifts too warm, the exhaust fan ramps up; once it’s back on target, it eases off. You set the goal; GrowRig does the minute- to-minute work.

Roles, not brands

Instead of “AC Infinity fan on plug #3”, you assign each piece of equipment a role:

• Exhaust — pulls hot, humid air out of the tent.
• Intake / circulation — brings in fresh air and keeps it moving.
• Main sensor — the temperature/humidity reading GrowRig controls against.
• Light — your grow light, on its schedule.

Because roles are separate from the actual hardware, you can replace a fan or sensor later and everything keeps working. This is the heart of GrowRig’s device model.

Safety is built in

GrowRig controls real equipment, so safe behavior is a core part of the design, split across layers:

• The Grow Controller keeps fans at a safe speed even if it loses contact with the Hub, and reacts to an emergency over-temperature on its own.
• Grow Core watches for stale sensors, enforces limits, and raises alerts.
• The app always shows why something changed and which reading caused it.

You can read more in Safety & security.

Next

Know what the system is made of? Next, see what you’ll need to build one — including recommended gear if you’re starting from scratch.