Hi. We've been away for 6 weeks and turned our water off. When we came back we found a rat had chewed through a PVC water pipe under the kitchen and no water coming through. We got our plumber out who fixed it, so we thought all good. After turning the water on again, after a couple of hours our hot water cylinder was still filling up and not heating. It's in our ceiling. I've been up there and there are no leaks from the hot water cylinder or of the any piping in the roof. You can hear the water going through the pipes in the walls to the hot water cylinder. I've turned the water off at the mains and wondering what to do next. Do you think another rat chewed through pipe? The cold water pressure in all parts of the house is fine, so not sure where the leak could be. Any thoughts? Much appreciated.