The water bill arrives and the consumption is higher than normal. In looking at the bill you realize it's winter time, your water consumption is down, but the bill says it is up as if its summer when your water consumption is higher. Then it hits you trustworthy plumber a water leak! At some point almost all homeowners run into this problem.
When you get to the house stand if front of the toilet and locate the water shut off valve. Should be down below the toilet on the wall. Just turn it off (righty-tighty) completely and flush the toilet. All the water should have left the tank, well at least most of it. If there is remaining water line repair get it out with paper towels or a rag. The important thing is that no more water came in. If it did then your valve is not shut all the way or not working and you need additional help.
If you bought the same unit it should line right up, if you were unable, you will need to remove or add length to the existing piping. This may require you to splice together copper with plastic, don't let this scare you the hardware store will have all of the necessary parts.
Once you have disconnected the tank remove it from your work space. Do a thorough measurement of the remaining pipe for reference when you go to the hardware store. I will be honest with you, you might need to make a few trips back to the store. Once you get the new tank, slide it into place to line up the plumbing.
If the area around the fan isn't clean and dry, or if dust or any sort of growth has accumulated on the blades or inside the exhaust duct, it may be a warning sign of excess moisture build-up. Clean the water line repair fan and area well. Then double- check that the fan is operating properly.
Plumbers should always have a durable and long lasting ventilation system ready for any job. Having clean air in ready supply can make many tougher jobs go much more smoothly and will cut down on the risk to the plumbers considerably.
A large plumbing job, such as re-piping or installing additional fixtures, may require a permit. Check with your city's department of building and safety before asking for estimates, and avoid any plumbers who are reluctant to comply with regulations.