Copper is a soft metal that can be easily drilled through with a high-speed steel drill bit. However, if you want to drill several holes, a carbide or cobalt-tipped drill bit is a better and more durable option. The trickiest aspect of drilling through copper is determining if it is a copper tube or a copper pipe. If you are not sure what type of material you have, contact your local heating supplier. They will be able to help you determine whether drilling is possible and provide you with the correct bit for your application. Once you have determined that you will be drilling into copper, make sure that you use protective gear. Wear gloves, safety glasses, and a heavy-duty dust mask. Also, make sure that you clean and dry your work area after drilling into copper. If you are planning on using copper for heating water, check with your local building department to make sure that you are not violating any plumbing codes. Some communities require that exposed pipes be insulated to prevent heat loss/gain. Other than that, there should be no problem using copper for hot water. Drilling into copper is easy if you follow some simple instructions. First, measure out exactly how many holes you need and divide that by four. This is how many total holes you will need. Then, take the number from step one and subtract it from this value. This is how many holes you need for your drill bit to fit properly.