Hammies should always have a wheel
He needs the option to use it when he wants - our hamster only ever uses it after we've gone to bed. It's about the only real exercise they get and they really need to exercise. Try putting a bit of substrate on top of it before you go to bed and see if it's gone in the morning - I bet it has! Sometimes our hammy wouldn't use his wheel for about a week after it had been cleaned because it smelled different, but I followed a tip to put a treat in it and he started using it again.
Wheels do take up a bit of space and it's partly why bigger cages are easier to set up. What cage have you got for him? If it's a bit on the small side then upgrading it or making a bin cage could be an option. They need a lot of space.