Hi,
Cold water is getting into our hot water feed, just had a new boiler put in and noticed the water temp had dropped a lot, especially upstairs, the installer checked and the boilers running fine and installed correctly. He switch off the feed from the boiler but we still got cold water from the tap, he thinks their must be a cold water line incorrectly connected to the hot line, said our old boiler must have been running very hot and maybe masked the problem. Does anyone seen this issue before? Someone also said it could be a problem with one of the shower mixer units allowing cold water back into the hot line.
