See below for some of our more Frequently Asked Questions 

Why do I need aeration and what are the benefits of having a controller?

You’ve spent all season tending to your crop with countless hours, effort and money to make sure it’s the best it can possibly be. So you should be doing everything possible to protect that investment now that it is at a stage of physical value. 

Aeration alone is simply not enough unless you are going to sit and monitor it all day; it is far too labour intensive to do properly on your own. This is where the GrainSafe products take the time and hassle out of grain storage by monitoring conditions 24/7 to ensure that your grain is kept safely and at the highest quality for extended periods. With a variety of different modes it is suited to protecting your investment in a variety of different conditions.

How often should I be checking my storage facility whilst I have grain in storage?

We recommend checking the operation of both the fans and controller every month.

The GrainSafe products come with a built-in ‘Test’ function that allows you to systematically check the operation of fans and the controller.

Can I run aeration fans or an aeration controller if I have no or insufficient mains power at site?

Yes, we can size and assist with the purchase of a generator and then provide all electrical equipment required to operate the generator, fans, the controller and any other grain handling equipment that may be onsite.

This involves an automatic generator startup when required, as well as a warm up phase before drawing any power. Control of separate sources of power when both generator and mains power are available can also be handled.

Will controlled aeration get rid of my insect problem?

While we have many customers tell us “yes”, the fact is that hygiene is 70% of the battle.

Other factors that contribute to minimising insect infestations include ensuring that the silos are cleaned out properly when empty (as much as this goes against the grain, leaving the fill and outlet hole open allowing the silo to heat and cool with day/night time cycles), moving all unnecessary equipment away from the storage site and ensuring all grass is kept down, and any spills are cleaned up.

Why would I purchase a controller rather than just continue using manual or timer operation for my fan operation?

The GrainSafe products take all of the guesswork out of aeration. It is constantly monitoring 24 hours a day, 7 days a week to ensure your grain is receiving the best air available, no matter the conditions.

It is constantly adapting to the conditions at your storage and making sure it is selecting the best possible air available, even in harsh conditions. Although the cost of a controller can seem daunting, some simple math suggests that a controller worth approximately $4000 protecting five 200T storages over a period of 10 years is only worth 40c per ton of grain stored.

How difficult is the controller to operate and what do I have to do to make it work properly?

The controller is completely automated, so when you first put grain into the silo simply select ‘Auto’ mode for the desired storages and the controller will take it from there. It will run through the initial ‘Purge’ cycle to remove harvest warmth and start to create uniform grain moisture and then transition into ‘Protect’ for long-term storage.

There are more modes available for anyone wishing to control their storage differently and an online demo can easily be requested to have a look at the system itself.

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What airflows do I need when setting up my silos?

The industry standard for aeration cooling is 2 to 4 litres/second/ton and ambient air drying requires higher airflows of 15-25 litres/second/ton.

I want a controller that can operate my aeration fans, as well as other grain handling equipment at my complex. What are my options?

We have a variety of solutions that are adaptable to each individual situation.

We can automate and control all other equipment onsite from the same electrical cabinet and in an easy-to-use interface. This includes, but is not limited to, elevators, roller mills, overhead unload bins, drag lines and many more.

My fans seem to be running at irregular times, how do I know if my controller is working properly?

The GrainSafe 7000 is controlled by Wet-Bulb temperatures, which exploits the relationship between temperature and humidity and how it affects grain. This means in extended hot periods the controller may run during a period of warm air but low humidity (a low wet bulb temp) to catch up on fan run hours and ensure the grain in storage is still receiving the air it requires.

The opposite can also occur at night-time when the air is cool, but the humidity may be higher and you might be concerned about rewetting the grain. This is also no cause for concern, as the figures below indicate that cooler air can simply not hold a lot of moisture, so it is the best for cooling the grain quickly and maintaining quality.

30°C100%30 grams/cubic meter of air
20°C100%17 grams/cubic meter of air
10°C100%9 grams/cubic meter of air


If your question isn’t among them, don’t stress

Simply send us a message and someone will be in touch with you shortly.

Contact us


Reach out to the Control Unlimited team today

07 4634 4706

Unit 1, 15 Freighter Avenue,
Toowoomba Qld 4350


One of our friendly team members will get in touch with you to answer your questions and discuss your requirements

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Send us a quote for Grain Aeration Solutions

Control Unlimited are ready to assist you with everything from Grain Aeration Controllers right through to installation and service.

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Let us know some detail about your situation. One of our friendly team members will get in touch with you to answer your questions and discuss your requirements

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Contoller Software demo

This demo really isn’t a big commitment or difficult to do. Please see below for our demo process: 

  1. Request a demo using the form below. This will then send us an email with your details. 
  2. Your details are then entered into our system as soon as possible and then immediately assigned to the demo controller. 
  3. You will receive an email with your username and password. 
  4. Head over to and enter the details in the email we sent you. You will have access to the controller we have in our workshop. 
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