Does my lender not want me to refinance to a 15 yr?

[Paul W.]

I have a rental that used to be my primary residence. When we moved we refinanced to a 30 year. 4.75, non primary residence loan. About 4 years later now I have 100k equity in the property and 140k left to pay. I pay an addition 150 a month on it so my payment is about 1050 a month. If I refinanced to a 15 year, my payment would not go up a whole lot and I would be saying a huge amount of money in interest and several more hundred dollars a months towards principal. My lender says it doesn't make sense and to just keep paying more on principal if I wanna pay it down. Well of course he does because he is still making more on the interest? Does this make sense ? Do lenders not want to refinance to a 15 so they can keep there higher interest payments ? And at what point do you just go to a different lender? If I went straight to a 15 I would be saving 50k plus in interest Thanks