Control Freak 5-Amp Plug-In Fan Speed Controller — Simple Temperature Control for Any Grow Room
Best for: Budget growers and smaller setups wanting automatic temperature control without the premium price tag
Our thoughts
If you've got an extractor fan that's either too hot or too noisy, this solves both problems. The Control Freak is dead simple — plug it in, set your temperature, let it do the work. One we recommend a lot for first-timers and anyone running a single fan. Does exactly what it should without overcomplicating things.
The Control Freak is a plug-in fan speed controller that gives you full control over your intake or exhaust fan with the turn of a knob. Run it manually for day-to-day adjustments, or plug in the included 5-metre temperature probe and let it regulate your grow room temperature automatically. It's the entry-level way to stop your setup from getting too hot or too loud, and it actually works.
Designed for duct fans up to 1150 Watts (5 amps), the Control Freak handles most standard extractor fans without fuss. No complicated setup. No app. No overengineering. Just plug, twist, and grow.
How it compares
The Control Freak sits firmly in the budget-to-entry tier of fan speed controllers.
- Simple manual control or full automatic temperature regulation — your choice
- Accurate to ±1°C when using the temperature probe
- Five times cheaper than premium hybrid controllers with silent operation
- Does single-fan control well; not designed for dual-fan setups
- Digital pulse-width modulation means a slight hum — that's the trade-off for the price
In plain terms: if you want proper temperature control without spending £300, this is where you start. Larger setups or noise-sensitive growers might stretch to a premium hybrid, but for most small rooms, the Control Freak does the job properly.
Usage guidance
The Control Freak works in two different ways depending on how you want to run it.
Manual mode (without temperature probe)
Plug the controller into mains, plug your fan into the front socket, and use the speed dial to increase or decrease airflow as you need it. Adjust on the fly — useful if you're actively managing temperature or noise levels during the day.
Automatic mode (with included temperature probe)
Plug the 5-metre temperature sensor into the socket on top of the unit, set your desired room temperature, and let it work independently. The controller scans the room, then adjusts fan speed automatically to maintain that temperature. When things heat up, the fan spins faster. When it cools down, it backs off. Dead simple.
Seasonal adjustments
In summer, run the fan faster to pull heat and humidity out. In winter, slow it down to stop your room getting too cold — especially during lights-off periods when extraction at full speed can kill your environment. This is where the Control Freak earns its keep.
Temperature accuracy
When using the probe, temperature adjusts in precise 1°C intervals, so you can dial in exactly what you need. Set it to 22°C and it'll hold it there.
One important limit: Do not use this controller with circulation fans (desk fans, pedestal fans, clip fans). Those fans have their own speed controls and the Control Freak will burn out either the fan or the controller. This is for duct extraction fans only.
Technical specifications
- Maximum power capacity: 1150 Watts (5 amp current draw)
- Control type: Manual dial or automatic temperature regulation
- Temperature probe length: 5 metres
- Speed settings: 50 variable speeds
- Temperature accuracy: ±1°C
- Temperature adjustment increments: 1°C intervals
- Operation method: Digital pulse-width modulation (PWM)
- Plug type: Standard UK mains 3-pin
- Noise level: Slight audible hum (inherent to PWM technology)
- Incompatible with: Isomax fans, circulation fans, any fan with built-in speed control
Who this is for
- First-time growers setting up their first grow room or tent
- Budget-conscious growers who want temperature control without premium pricing
- Anyone running a single extractor or intake fan up to 5 amps
- Growers dealing with seasonal temperature swings and noise complaints
- Small to medium setups where a simple, reliable solution beats fancy features
Particularly well suited to anyone tired of their fan running flat out all year, wasting energy and creating unnecessary noise.
Our take
Temperature control doesn't need to be complicated or expensive. The Control Freak does one job — adjusting your fan speed to keep your grow room at the right temperature — and does it properly. Manual or automatic, it works. The slight hum is the only real compromise for the price, and honestly, most growers don't notice it once their setup is dialled in.
If you're building a small grow room or tent and want to stop fighting temperature swings, this is worth picking up. Good time to buy while stock lasts.
