Like it or not, winter is around the corner. And with more tractors on the market meeting Tier 4 emissions standards, there’s more diesel exhaust fluid (DEF) being stored on-farm.
DEF itself is a solution of 32.5 percent high-purity urea in de-mineralized water. It is used with Selective Catalytic Reduction systems (SCR) to reduce nitrous oxide emissions from the exhaust systems of diesel vehicles.
As part of this week’s Rocky Talk on RealAg Radio, we chatted with Joel Hoehn of Rocky Mountain Equipment about how to handle DEF during the farming off-season:
- The biggest thing: keep it in a shed out of sunlight. The urea is vulnerable to degradation from the sun.
Freezing has no effect on quality or performance. Room should be left for expansion.
If you can, reduce the amount of DEF you have on-site for winter. Hold a bulk pre-order until late winter or spring. The urea will degrade over time.
Keep it in plastic or stainless steel tote or container.
Make sure lids are sealed and airtight or crystalline material can appear with evaporation.
Drain DEF systems on larger machines — combines, sprayers — and rinse out with water. DEF is corrosive so rinse spillage off the frame.
Don’t hit battery disconnect right after parking it for winter storage. Leave connected for half an hour after. “What this does is allow the machine to purge the DEF out of the lines and out of the injectors to prevent any frost damage or expansion damage due to freezing. It’s way better for your machine,” notes Hoehn.
Keep a small amount in the house or warm shop in case you need to start a machine in the cold. “Keep a couple gallons if you have to bring a machine in. Keep a gallon or two of warm DEF in your house in small containers, just dump it in before you drive it to town, and you shouldn’t have any problems.”
Most suppliers say DEF will last six months to a year, when stored properly, before the components begin to settle or degrade.