Hi there, new to this form - please can anyone offer advice - my conservatory guttering has been overflowing lately, and after investigation today, I find that the downpipe junction was blocked initially with moss, but when I cleared this away, I find the drain hole from this gutter to the downpipe is reduced in aperture, and not the size of the down pipe bore. I estimate the aperture diameter to be around 25mm where as the downpipe diameter is as standard. Why would this restrictor be fitted in the first instance and can this restriction be easily removed to match the diameter of the downpipe?