Petrushina, I. Hayes, T. Jing, Y.C. Kayran, D. Litvinenko, V. Mihara, K. Narayan, G. Pinayev, I. Severino, F. Shih, K. Smith, K.S. Wang, G. JACoW Geneva, Switzerland 978-3-95450-179-3 10.18429/JACoW-FEL2017-TUP034 English 313-316 TUP034 ion gun electron simulation cavity Contribution to a conference proceedings 2018 2018-02 https://doi.org/10.18429/JACoW-FEL2017-TUP034 http://jacow.org/fel2017/papers/tup034.pdf A 15 MeV CW SRF accelerator had been commissioned at Brookhaven National Laboratory to test the coherent electron cooling concept. The accelerator consists of an SRF 113-MHz photoemission gun, two 500 MHz bunching cavities and a 704-MHz 5-cell SRF linac. In this paper we describe our experience with this system with focus on unusual phenomena, such as multipacting in the SRF gun. We also discuss issues of wakefields in the CeC accelerator.