What I have done, I have briefly checked all the radiators for leaks, PRV doesn’t seem to be passing, checks for leaks inside boiler.
There are 3 pipes on my outside wall, one being the PRV, one the flue?? and the other was a white PVC pipe that has been directed over guttering/drain. This was blocked and the end of the pipe was submerged in water, I have now cleared the drain so the pipe is free. Any ideas what this pipe does and would it being submerged in water effect the use?
Also worth noting I don’t think the boiler has ever been serviced or checked over, not sure on age but I’m gonna say 10 years old.