Comments on the system operation:

1-DPF was installed on the bus on 2015-01-28.
2-DPF core was replaced by muffler on Jul 22nd and was cleaned and reinstalled on the bus on Aug 12th.
3-Considering system relatively high backpressure, filter isolation defect and air filter’s deformation, DPF core was removed on Sep 16th and installed on Nov 17th after cleaning and system improvement.
4-The third cleaning was unavoidable after only 6 days working and was done on 2015-11-29. System only worked for two days and DPF was replesed by muffler on 2015-11-30.
5- DPF was cleaned and installed for the fourth time on 2016-01-19 and was replaced by muffler after only three days working because of high backpressure.
6- A new core was installed on 2016-05-14.
7-DPF was cleaned on 2016-06-25.
8-DPF was replaced by muffler on 2016-07-10 due to high backpressure.