The Swedish brand installed heater, after 25 years of service was damaged. The hot water installation of the house is composed of two showers, two sinks and a dishwasher in the kitchen. There are no offers of the same brand. There is a natural gas passage heater with natural gas outlet, that is, it uses pipelines to extract gases outside the same as the damaged one. The replacement heater is 12 liters. Can pipes used to service the damaged heater be used or should they be replaced? All copper and PVC hot water pipes appear to be in good condition. I await your advice on this, since I am not an expert on the subject. I am only the owner of the house. Thanks in advance.