I purchased a new faucet with sprayer. Currently I have a faucet but no sprayer.next to where the sprayer should go, there is a overflow for my dishwasher. Do I need to drill another hole or do I need to do something with the overflow ?
You will need to drill another hole. The overflow you mentioned is called an Air-gap. It prevents the dishwasher drain from pulling a vacuum on the sink drain. They were required in some areas but now are being omitted from some codes.
The overflow is there so that if your kitchen sink clogs then it does not fill up your dishwasher with nasty sewer water. If you take the overflow (called an Air Gap) out then you would have dirty nasty water going into your dishwasher with your dishes. You can drill a hole in the sink but I warn you that this is difficult to do. I would recommend purchasing a pull out sprayer faucet. It's more costly but will save you the trouble of drilling a hole. They also make faucets that have the sprayer hole built in to the body of the faucet but this looks a little weird. If you get the pull out sprayer then you will like it and it looks nice too. So, just shell out a little more money and get a good faucet that looks good too!
you can probably re-work your dishwasher drain line under your sink drain, which removes the need for an overflow. Usually, these drain into a disposal anyhow. Then perhaps the existing hole will be sufficient. Take a look at a friends under sink plumbing to get ideas.
