switch ?

[union pacific 844]

can dc switches converted to dcc?

[Doneldon]

844-

If you mean electrical switches, yes. There are no differences between switches for DC and switches for DCC.

If you mean turnouts, again there is no difference. Both DC and DCC trains will run through your remote turnouts just fine.

However, I'm guessing that your question is really, "Can I rig my remote DC turnouts so they're operable under DCC?" If so, the answer is "yes" but it's probably not worth the effort if your turnouts already work remotely. Since the turnouts are already wired and working remotely under DC you must either 1.) replace the existing turnout with a DCC turnout or 2.) attach a DCC stationary decoder to tell the turnouts when to change direction. This will require either using a separate DCC-operated electrical supply buss for the turnouts (possibly with its own DCC system), or that you disconnect the already-wired remote controllers, run wires from your DCC tracks to new DCC stationary controllers and then run wires from those new DCC stationary controllers to the existing switch (turnout) machines. Hence, the reason I say it's probably too much trouble to be worth the time and effort.

Your easiest option is to continue to use your existing remote control system. The only thing changing your turnouts to DCC will do is allow you to control them with your DCC controller or DCC throttle. I suppose that could be worthwhile for a large walk-around layout where returning to an existing control board would be inconvenient, but I'm not so sure it would be worth it on a smaller layout, at least to me. I suggest that you draw up a plan, identify the components you need and check the overall cost before you make a final decision.
                                                                                                                            -- D