Hi we have been having issues with our boiler the codes 110/125 come up when trying to run hot water. The heating however works. We have bled radiators to release any air etc but the pipes are tinkering when heating is on,and on closer inspection I have found a leaking part on the boiler pipes and the pipe has discoloured, I wanted to check if it needs a plumber to fix and if the black lever is in the right place before we get someone out. The leak is coming from the section above where I have put the white tape thanks all.

