Running out of AdBlue® is one of those problems that is completely avoidable, yet it still catches sites out. A truck goes into derate, a loader sits idle, and someone is sent off to buy drums at retail. On the other side, an overfilled tank during a delivery means spilled product, white urea crystals on the slab and a clean-up job. Good tank level monitoring solves both problems, and it does not need to be complicated.
Why guessing the level costs money
Most sites start by dipping the tank or looking at a sight tube. That works when one person owns the job and checks it every week. It stops working when that person is on leave, when usage jumps because of a big contract, or when the tank sits behind a locked cabinet nobody wants to open.
The usual results of guessing are:
- Emergency orders — small, urgent deliveries or retail purchases at a much higher cost per litre.
- Downtime — vehicles with empty AdBlue tanks go into reduced power and can't be dispatched.
- Overfills — a tanker driver filling to an estimated level can overrun a tank that was fuller than expected.
- Old stock — ordering too much "just in case" means product sits longer, and shelf life shortens in hot weather.
Because AdBlue use typically runs at about 3–6% of diesel use by volume, you can estimate demand, but real consumption varies with load, terrain and idling. A gauge tells you what is actually happening.
Types of tank level gauges
There are three broad levels of monitoring, and many sites combine them.
Mechanical and local gauges
A float gauge or sight level on the tank gives a quick visual reading. It is simple and needs no power, but someone has to walk out and look at it.
Electronic level gauges
Electronic gauges such as the Piusi OCIO use a sensor in the tank and a display unit mounted inside the workshop or office. Staff can see the level without going outside. These suit fixed sites with a 240 V supply and a tank close to a building.
Remote monitoring
Remote monitoring sends the tank level to a phone, web dashboard or your supplier. This is the most useful option when tanks are spread across depots, on farms or at sites nobody visits daily. It also lets the supplier see when you are getting low and plan a delivery before you have to call.
Whatever sensor you choose, it must be compatible with AdBlue. Wetted parts should be stainless steel, HDPE, polypropylene or other compatible plastics, with EPDM or fluoroelastomer seals. Brass or aluminium fittings will corrode and contaminate the product.
High-level alarms and overfill protection
A high-level or overfill alarm is a separate safety device from the gauge. It sounds or flashes when the tank reaches a set point during filling, giving the delivery driver time to stop. On bulk tanks receiving tanker deliveries, this is a sensible minimum.
Remember that AdBlue expands roughly 7% when it freezes at about −11°C. In areas that get hard frosts, don't fill a tank to the brim. Leave headspace and set the alarm point accordingly.
For bunding and storage requirements, check with your state EPA and your own site rules. An alarm reduces the chance of a spill but does not replace containment where it is required.
Setting up scheduled refills
Once you have reliable level data, scheduled refills become straightforward. There are two common approaches:
- Fixed schedule — a delivery every set number of weeks, sized to your average use. Simple, and it works well where consumption is steady.
- Trigger level — a delivery is booked when the tank drops to an agreed level, for example 30%. This suits sites where use goes up and down with seasons or contracts.
With remote monitoring the trigger approach can run largely on its own: the supplier sees the level fall and books the tanker. Your job becomes checking the invoice rather than chasing stock.
Keeping a safety buffer is still wise. The late-2021 urea shortage showed how quickly supply can tighten in Australia. A trigger level with a week or two of stock in reserve gives you room if freight is delayed.
Something you can do today: look at your last three months of AdBlue invoices, divide the total litres by the number of working days, and work out how many days your current tank lasts from full. Set your reorder point at no less than the delivery lead time plus a week of buffer. Write it on the tank until you have a gauge that does the job for you.
Keeping the system reliable takes a few simple habits:
- Check the gauge against a manual dip every few months.
- Keep sensor heads and cable entries sealed so dust and water can't get in.
- Clean off any urea crystals around fittings — they can jam floats and switches.
- Test the high-level alarm before a delivery if it hasn't been triggered in a while.
How Liquidia can help: Liquidia supplies on-site tanks with remote tank-level monitoring, Piusi gauges and scheduled refills, so your supply runs on real levels rather than guesswork. See our bulk and on-site tank options or browse gauges and alarms in the accessories range, and ask us for a quote.