DPF Cleaning

DPF Cleaning

DPF Cleaning

DPF Cleaning ($230) on a regular basis will save you time and money in the long run

Along with your annual inspection, regular DPF cleaning is the most effective way to avoid emission control related breakdowns.  DPFs (Diesel Particulate Filters) are one of the most common reasons for breakdowns today.  Central Alberta Heavy Duty Repair has cutting edge machinery from FSX for cleaning DPF filters, resetting your ECM, and getting you back on the road.  As well, we are fully equipped and trained to diagnose problems with SCR or Selective Calatyltic Reduction systems, which when malfunctioning, can cause improper engine operation and even derating.

Many owners have opted for DPF delete systems, which solve some issues relating to clogged filters, but sometimes create other issues with the ECM and fuel delivery controls.  The simple truth is that the DPF and SCR systems were poorly engineered to begin with and were not designed for long periods of idling in cold Alberta winters.  The best course of action to avoid breakdowns is to have your DPF and SCR systems cleaned and calibrated regularly.  After all, torque derating due to clogged DPFs sometimes can only be reset by OEM scanners, even after the system has been cleaned.  Avoid a costly roadside service call and have your DPF cleaned regularly. Please see below for our DPF cleaning prices:

Regular Pneumatic Cleaning        $230

Heat Treatment                               $425

These prices do not include removal and installation of the filter.

How does DPF cleaning work?

First lets start with an explanation of DPFs themselves.  DPF filters are large ceramic blocks with long thin holes running through them (like a bunch of straws tied together side by side).  Half of the holes are capped on the inlet side of the filter, and half of them are capped on the outlet side.  As the exhaust gas from the engine enters the filter, it flows into the uncapped holes.  The pores in the walls of the ceramic tubes are large enough for gases to pass through but not big enough for diesel particulates to pass.  So the exhaust gasses pass through the tube wall to another hole which is open to the filter outlet side. The particulates, however, are trapped inside the filter.

The particulate that gets trapped inside the filter is a mixture of soot and ash from the combusted diesel fuel.  Basically, ash is good.  it represents fuel that has completely burned and there is nothing left but a fine dry dust-like substance.  Soot is different.  Soot is made of small particles that still have some content of unburned fuel in them.  (This is what you used to see coming out the exhaust pipes of trucks).  The DPF filter system is designed to burn up all the soot.  Because the DPF filter is ceramic, it can withstand high temperatures.  So, as the engine runs, the exhaust gasses heat up the ceramic filter and then when soot collects in the filter, it eventually burns up and turns to ash.

Occasionally, the control system on an engine senses that the DPF filter is getting clogged (it senses that there is a reduction in flow or an increase in pressure in the exhaust due to less flow through the filter)  At this time, the control system initiates a 'regen'.  Basically, this is the engine and filter system trying to clean itself.  The engine will maintain a high idle and sometimes an abundance of fuel will be run in an attempt to clean the DPF filter by burning out all the soot.  This 'regen' process is a normal and necessary function of the engine.  For the most part it works very well and should be left to run its course whenever it occurs (unless the truck is in a hazardous situation).  Many DPF issues are caused because drivers override the 'regen' process because they want to save time.  The other condition that quickly clogs DPF filters is excessive idling.

After some time, the ash builds up inside the filter and must be cleaned out.  This is where the DPF cleaning comes in. The cleaning process is comprised of high-pressure, high volume blast of air that is simultaneously applied to both sides of the filter.  These conflicting jets of air disrupt the ash off the filter and blow them out so that the dust can be collected.  This process is called pneumatic cleaning.

On average, about one out of every 7 or 8 filters has too much soot stuck in the filter to be adequately cleaned.  In this case, a heat treating process is used.  The filter is put in a kiln that heats the ceramic filter and burns out the soot. Once all the soot has been converted to ash, the filter can be blown out again.

Finally, the DPF filters are tested to make sure they have been adequately cleaned by testing the air flow through the filter.

Top ten things to remember about DPFs and DPF cleaning.

  1. Remember that DPFs are like a bunch of straws taped together.  As each straw fills up with ash, there is less surface area for gas to flow, so as the filter gets more clogged, you are losing exhaust flow which means less power and less fuel economy.  The loss in fuel economy would probably offset the cost of cleaning each year.
  2. Again we refer to the straw analogy.  If you think of a straw filled with dust, or a straw 1/4 filled with dust, which one do you think is more likely to be successfully cleaned?
  3. DPF systems are constantly trying to deal with soot.  A 'regen' is your engine's way of trying to clean itself and run better.  Let it run its course.
  4. Engines are not running efficiently when they are idling.  Idling means more soot, which means more 'regens'.
  5. Ceramics are meant to tolerate heat.  However, the extreme temperatures occurring during a 'regen' or during a thermal treatment push them to the limit of what they can tolerate.  The fewer 'regens' and thermal treatments the better.  The best way to keep DPFs healthy is to have them pneumatically cleaned regularly.  The better they flow..the better they work in normal operation... the less frequently they need to 'regen'
  6. The only thing worse than soot is oil and antifreeze.  If either of these chemicals end up on your DPF, it often means that the filter needs to be replaced.  Keep your engine in good condition.
  7. DPFs are ceramic.. they are quite fragile.  Don't drop them upon removal or installation.
  8. THE NEXT ITERATION OF THE ALBERTA COMMERCIAL VEHICLE INSPECTION MANUAL WILL MAKE DPF SYSTEMS MANDATORY.  If you are going to perform a DPF delete, keep the DPF equipment.  There is a good chance you will have to put it back on sometime in the next year.
  9. Central Alberta Heavy Duty Repair will pick up and deliver your DPFs in Red Deer.
  10. Central Alberta Heavy Duty Repair now has access to aftermarket DPFs.  Please call for pricing.