What happens if water gets into red diesel?

In brief

Water is where most diesel problems start. It corrodes tanks and injection equipment, freezes in winter, and gives diesel bug a place to grow at the boundary between fuel and water. The biodiesel in modern diesel holds more dissolved water than pure mineral diesel, so it is more prone to it. Not until the free water has been removed and the fuel checked. Running an engine or boiler on wet fuel risks corrosion, misfiring and blocked filters. Call 07950 582635 or send an enquiry.

How water in red diesel happens

Condensation forms inside tanks as they warm and cool; rain gets in through worn fill caps, vents, seals and hatches; and floods or a high water table push water in through fittings.

Is red diesel contaminated with water still worth collecting?

Usually yes. Free water settles and is drawn off, and the fuel above it normally keeps most of its value once filtered. Water reduces the value of a load roughly in proportion to how much there is. A little water barely changes the terms; a load that is mostly water may carry a charge.

How City Fuel Services handles waste red diesel

Send us the five details: business and postcode, roughly how much waste red diesel there is, what it is and any contamination, how it is stored and reached, and whether you need one collection or regular ones. We assess it, confirm a rebate or a collection charge, and collect on a consignment note.

Terms used in this answer

Diesel bug: Bacteria and fungi that grow where water meets diesel in a tank. They form slime and sludge that block filters.
Mixed fuel: Petrol and diesel that have ended up in the same container, usually when vehicles are drained during depollution.

Key facts
Problem	Water in Red diesel
Recoverable?	Usually yes.
Fuel	Red diesel
Also called	gas oil, rebated diesel, marked gas oil
Waste code	13 07 01* (fuel oil and diesel)