I am trying to put in a ceiling fan that was pre-wired to a dual light switch. When I took down the original light I found that I had lots of wires in the box. I had two white wires together, and two black wires, I also have a single white wire, a single red wire, single black wire, and a grounding green wire. The previous light was attached to the two white wires and the single red wire. The fan has a white, a blue, a black and a green wire. I don't know how to attach the white, blue, and black wires so that my dual switch will work.

There should have been a wiring diagram with the ceiling fan. Follow it or find a diagram on the net to use. Most of the colors used are universal so most fixtures will be the same.

When you say single wires, do you mean ones that are unconnected but bundled together in cables or conduit? If so, I would leave them unconnected. They may have once run to a no longer existing fixture, perhaps spackled over, a questionable practice.

Identify which red and black wires are hot went the switches are on. I like my voltage detector* for those jobs. Connect white to white, hot black to fan black, hot red to fan blue, and all the bare and green together. Unless you have something else that should be on with the fan, cap the other wires and leave them unconnected.

*To do simple checks like this you do need some tools. A test light, a meter, or a voltage detector might be the best place to start with. I came across the niftiest gadget for trouble shooting, a voltage detector. They work through the insulation of wires. There are several brands. I have a GB Instruments GVD-505A, less than $15 at Home Depot. Touch it to a hot wire, and the end glows red. Find the doodad that lights it on one side, and not the other, and you have the culprit. You do not have to open up housings and expose electrical contacts. You are looking at where your hand is, not where the meter is. Most people are capable of doing repairs and will get it going and not get hurt if they use a little sense. The voltage detector makes it even easier.

How many wires does your new wall switch have?

AND

How many wires are in the wall where the switch will connect?

This may be VERY easy or a little tricky.

Ceiling fan wiring - Ceiling Fans N More