A7. To do the perfect sizing, you need to ensure how many people live in your home. The sizing should be based on a few factors like the size of your house, the faucets that you will use the members, the rate of water flow, and the type of ignition. According to this, you can choose the right size. You can collect all the data and then keep the purpose of your use. Based on all these factors, choosing the right size of the AO smith model will be perfect.