More generally speaking, AFAIK any "color" enlarger can be used to make B&W prints. (I'm sure somebody will point out the one exception, if there is one. ) "Color" enlargers simply contain built-in adjustable filters to adjust the color balance on color papers. (Older ones just had filter drawers.) These filters are actually useful for B&W printing on variable contrast (VC) paper, since these papers use yellow and magenta filtration to adjust the contrast of the finished image. Consult your enlarger's manual, the data sheet for your paper, or a general introductory book or Web site on B&W printing for further information on doing this.
If you use graded paper (fixed contrast), set it all to 0.
For VC paper you use the yellow and magenta dials to change the contrast. I also use the fourth wheel, the white one, to fine-tune the light output so I can make all prints at the same exposure time. I use a cheap Ilford EM-10 to measure the light - set it to a fixed value, put it in a highlight, then adjust the neutral dial until the diodes flicker. Then a 10 second exposure gives the same highlight value at all contrast settings.
Go to the Ilford web site here (http://www.ilford.com/html/us_english/bw.html). Scroll down and there is a PDF document called: CONTRAST CONTROL in the PAPER section. Download and read the PDF. It explains how to use a colour head with variable contrast paper.
The actual numbers in the document are aimed at Ilford paper of course, but the principles are the same for all makes of variable contrast paper (and the numbers will probably be close enough too).
If you are not using variable contrast paper then do as Ole suggests and leave all the colour settings on zero.