Hi RJNSilva,
We sell vacmaster sealers, and I also do the service and repair on them in my area and what I recommend to my VP215 customers is that they change the oil after the first 1500 cycles and then every 3000 cycles. Each cycle is one bag, so it's easy to track how many cycles you have on the machine by how many bags you have used. There are two important exceptions; if you have been sealing a lot of liquids and have moisture built up in the oil, making it a milky color or if you are going to store it for any significant length or time without using it. In both cases, the moisture, if left to sit for weeks/months on end can rust the internal components of the pump which is never good. But I also recommend keeping the VP215 close to the kitchen, if not directly in it because the longer you own one, the more you use it. Soon you will be infusing flavor into watermelon, marinading your pork, and of course, vacuum packing your bulk meats, etc.. I find that I use mine 2 or three times a day. Let me know if you have any more questions about the VP215. I would be happy to help.
Thanks,
Doug