How the MeatStick Blow BBQ fan controller worksThree parts, one loop.

The Wired Ambient Probe reads the temperature at the grate, the V Forge WiFi Hub works out how much air the fire needs, and Blow feeds the fire that air. That is all fire control is. People have done it by hand at the vent for a hundred years; Blow does it for you.

Blow mounted on a kettle with the lid closed, ports facing down, cables to the V Forge WiFi Hub on the side table, to power and to the Wired Ambient Probe — Blow Forge on a kettle, lid closed.

The basic idea

A charcoal fire runs on air.

A V Core Stick in the meat on an open kettle grill, flames rising from the charcoal — A charcoal fire under the grate, a Stick in the meat.

A charcoal fire burns as hot as its air allows. As the coals burn down and ash builds, the temperature drifts up or down.

So to control the temperature, you control the air.

More airHotter fire Less airCooler fire

How the parts work together

Every part has one job.

Put a Stick in the meat too, and the MeatStick app shows the cooker and the food together.

Diagram: the Wired Ambient Probe and the hub-link cable plug into Blow, and a USB charger powers it

Setup diagram. The Wired Ambient Probe and the hub-link cable connect to Blow, and a USB charger powers it.

The Wired Ambient Probe reads the pit
It reads at grate level, where the food is, not up in the lid like your lid thermometer. It reads up to 572°F, rated to 716°F, accurate to ±2.7°F from 212°F to 392°F. It plugs into Blow, which passes the reading to the hub over the hub-link cable.
The hub decides
It compares the reading to your target and works out how much air the fire needs. It does this on the hub itself, right at your cooker.
Blow feeds the fire air
A variable-speed fan gives the coals the air the hub asks for. One fan works on every supported cooker. Its brushless motor has no brushes to wear out and ball bearings at both ends, and it's built to keep running through a long cook beside a hot fire.

Where the reading comes from

Grate, not dome.

Your lid gauge reads the dome, well above the food. The Wired Ambient Probe reads at the grate, beside the food over indirect heat: the temperature your recipe means when it says 225°F. Expect it to differ from your lid gauge. That's the point, not a fault.

The Wired Ambient Probe held on a grill grate by its grate clip — The Wired Ambient Probe clips to the grate. Keep it beside the food, over indirect heat and out of the fan's airflow.

What normal looks like

The fan cycles. The pit wanders. It comes back.

Near your target the fan works in cycles. That's normal: it is adjusting the air in small steps to hold your temperature.
If the fan stops and the app shows the pit at or above target, that's normal. Blow switches the fan off on purpose so the temperature can settle, and starts it again when the temperature drops.
Charcoal is not an oven. Expect the temperature to drift above and below your target rather than sit on it, with the fan speeding up or easing off in response.
Lid open? Blow pauses the fan until you close it. Keep lid-open time short.

Pit at the grate

Fan off

Fire lit · fan at full

Pit temperatureYour set tempFan, off to full

Two real test cooks on a charcoal kettle with pre-launch firmware: lit from cold and set to 225°F, then a lid opening from a later lid test.

Meet Blow Forge

Watch it from anywhere

You don't have to stand by the cooker.

A man sitting on a park bench with his dog, checking the cook on the MeatStick app — Following the cook on the MeatStick app, away from the grill.

Cooker and food temperatures, live on your phone, wherever you are. Set a target and Blow holds it. Set an alarm and your phone tells you when something needs you.

Same app as your Sticks: one screen for the meat and the fire.

Where the control runs: on the hub itself, right at your cooker. WiFi only lets you watch the cook and change the target. If your WiFi or the cloud drops, the cook keeps running.

What if something goes wrong at 3am?

Built to fail in the safe direction.

The dangerous failure is a fan that keeps blowing air into the fire after something breaks. So Blow is built to stop.

It watches itself

If Blow's controller stops responding, a built-in hardware safety check (a watchdog) cuts the motor.

If it loses the hub, it stops

If Blow loses power or its link to the hub, the fan stops.

It notices bad power

Blow detects when its power drops too low (a brown-out), from a failing power source or a weak charger, instead of carrying on at half power.

Why a cable, not wireless? So the fire never depends on a radio link. A dropped WiFi or Bluetooth signal only costs you the view on your phone, never control of the fire. And there's no battery in the fan to run flat mid-cook. How Blow is built →

And if the fire runs low? The temperature drops even with the fan running. Add charcoal and check the vents.

Check the app now and then. With the cooker and meat temperatures on your phone, a fire running low is easy to spot.

Power

One cable, from a charger or a power bank.

A USB charger or power bank, 5V/2A or higher recommended, with the included USB-C to USB-A cable.
No charger comes in the box.
A lower-rated source still works, but the fan may not reach full speed.
For overnight cooks, a wall charger is the safest choice. Some power banks switch off when the fan runs gently, cutting power mid-cook.
The hub on long cooks. The V Forge WiFi Hub runs about 14 hours on battery and keeps running while it charges, so it can stay plugged in for long cooks.

Weather and the yard

Looking after Blow.

Blow on a backyard table — Blow on the table between cooks.

Mount it ports-down, so the ports face the ground.
Blow gets hot on the cooker. Keep fingers, hair and cables clear, and let it cool completely before handling it.
Bring it indoors to store.
Keep Blow out of heavy rain and spray.