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F.A.Q.
1. What is a DPF Filter? And why does it need to be cleaned? Diesel particulate filters (DPF'S) are emission control devices designed to clean the exhaust emitted by the vehicles' diesel engines. In a diesel particulate filter (DPF), exhaust gasses pass through the open end of a channel and at the opposite end is a plug that forces the gasses through the porous channel wall allowing the exhaust to escape through the neighbouring channel wall trapping as much as 90 percent of the solid particulate matter. The most popular type of filter is a “wall flow” filter which can remove between 90-100% of the particulate matter from the exhaust under proper operating conditions. Wall flow units typically consist of thousands of small (<1mm) alternately blocked rectangular channels in a ceramic core. 50% of the rectangular channels are inlet channels, in which ash/soot will accumulate and 50% are outlet channels, which under normal conditions remain clear. The thickness and porosity of the walls determine the efficiency of the unit filter and it is on the inlet side surfaces of the wall that the ash/soot collects. Ash/Soot collects at the outlet end of the filter channels and filter efficiency decreases over time until the unit becomes non-serviceable. Regenerative cycles are used intermediately to extend the DPF working life by combusting the accumulating soot to carbon dioxide and ash. Some DPF units utilize an oxidative fuel additive during the regeneration cycle to help promote the combustion of the soot in the unit. Some units simply heat and air to provide the necessary energy and some DPF cores are enhanced with catalyst to improve the regenerative performance. Regardless of the frequency and effectiveness of the regeneration, eventually the DPF will become fouled to the point that it is no longer operative, at this point the unit must be replaced or cleaned by another method. 2. How often should my DPF be cleaned? Unfortunately many vehicle dealers imply that all that is needed to keep the DPF clean is to hit the vehicle's “regeneration” button. While it's true that the regeneration cycle is necessary and will combust much of the accumulated particulate matter, non-combustible materials trapped in the filter will still be left behind, this remaining residue creates back pressure that will eventually lead to increased regeneration downtime, loss of horsepower, reduced fuel economy, filter damage and ultimately engine damage. The frequency of the DPF cleaning will vary by vehicle usage, in extreme cases the engine control will significantly reduce engine output or shut down completely should the exhaust back pressure caused by the DPF exceed critical levels. Recommendations for DPF service (removal of the DPF and cleaning by a specialized process) vary by manufacture and vary greatly with vehicle usage. The typical schedule would require DPF service every 250,000 km for light to medium duty operation, for smaller passenger and light duty diesel vehicles, DPF service may be required at much shorter intervals. 3. What benefits do I get with regular DPF cleaning? DPF cleaning will normally restore engine performance, increase fuel efficiency, reduce regeneration, extend filter life and overall reduce down time and maintenance costs. 4. How do I know the DPF needs cleaned? Increased frequency of regeneration cycles and loss of engine performance are the best indicators of the need for DPF cleaning. If you are operative under light load or frequent idle conditions, or if you notice a significant increase in regeneration cycles it is likely time for a DPF service. DPF Deep Clean's unique process can have your DPF cleaned in usually less than a working day meaning you are back on the road faster. 5. What is the DPF Deep Clean process? DPF Deep Clean has developed a 9 stage process which involves a non destructive proprietary cleaning process, a proprietary cleaning solution and high volume airflow to agitate and assist in the complete removal of ash/soot from the channels of the DPF unit. We will inspect the DPF on arrival and we will ask for some information about the reasons for failure. We will start by inspecting the DPF with our endoscopic equipment for signs of cell damage and oil damage, any units found damaged as a result of catastrophic engine failure may not be repairable and we will try to determine this at the outset of the cleaning activity. Through testing we determine if the unit is lightly, normally or heavily fouled and may adjust the return expectations based on this. We will weigh the DPF and airflow test for back pressure results, we will then place the DPF into the proprietary cleaning process where we agitate the ash/soot plugs which become saturated with liquid and softened. The ash/soot plugs are then washed out with low pressure rinse water and given a final rinse with fresh water. We then thoroughly dry the DPF and repeat the pre inspection of airflow for back pressure, the DPF is re-weighed and undergoes a final endoscopic inspection. Having confirmed that the cleaning has removed all of the ash/soot contamination, the DPF is then returned along with the paperwork showing pre-inspection and final inspection results. 6. How effective is the cleaning process from DPF Deep Clean? Results from both our R&D testing and in-house process validation checks have shown between 96-100% of accumulated ash/soot in a DPF are removed, the DPF returned to an “as new” condition and the back pressure generated by the filter is restored to factory specifications. 7. How long does it take to clean using your process? The typical time to turnaround a DPF is 4-6 hours. This time may increase
if we have a large number of DPSs in process, but we can let you know when the DPF will be ready for collection
or dispatch. In some cases where we have to deal with extraordinarily fouled/contaminated DPF'S, such as
catastrophic engine failure, we cannot reliably predict the cleaning time other than to indicate that it will
likely be longer. 8. Is the cleaning process safe for my DPF unit? Yes, because the non destructive proprietary cleaning process does not effect the DPF'S make-up and is gentle on the walls of the DPF along with the air drying process, the DPF is only subjected to its normal operating flows and pressure. We do not use high pressure air jets, or extreme temperatures, which may promote cracking of the DPF element. 9. I have a catalytic converter and DPF unit can they both be cleaned? Yes we can clean both even if they are integrated into a single canister. 10. Can you clean the EGR Valve? Yes, our process is suitable for cleaning the EGR valve. (Additional fee may be required) 11. The DPF is a single unit that cannot be disassembled, can DPF Deep Clean process it? Yes, because our process system is more flexible that high pressure air cleaning, we can clean DPF'S of any shape or configuration. 12. If I had a catastrophic engine failure, can my DPF be cleaned? We would in most cases say yes, even though generally engine oil will be shot into the DOC (Diesel Oxidation Catalyst) unit and the DPF. It will cost more to clean a unit which has been contaminated with oil or excessive fuel, but generally these can be cleaned for a fraction of the cost for a new system. In cases where the engine coolant has also contaminated the filter it may not be possible to clean the unit, in these cases the unit is frequently damaged beyond repair. 13. My DPF is completely blocked, can it be cleaned? It will depend on why the DPF is blocked. A severely filled DPF can often seem completely blocked but will clean normally. A DPF which has experienced serious overheating during regeneration can sometimes actually melt inside, which will destroy the DPS'S structure and cannot be repaired. 14. Is there any water left in the DPF after cleaning? By testing using a humidity meter we do not expect the DPF to be holding water, if there is a small amount of moisture left after cleaning (clean water) it will evaporate quickly once installed. In some cases, where a rush job is required, slightly more moisture may be left which will also blow off/evaporate in use.
15. How do I know if my DPF unit is damaged (Cracked)? Cracks in the DPF substrate are detected by two means.
16. How do DPF Deep Clean verify the results of cleaning? Cleanliness and performance of a DPF Filter after cleaning can be verified by our 9 stage processing being recorded and we will issue all test results as a method of recording onto the vehicle/plant maintenance records, detailing the contaminant levels pre and post cleaning. 17. Can DPF Deep Clean remove and refit the filter unit? We aren't currently able to provide that service. The DPF needs to be removed and replaced by your mechanic. | |||
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