Had a Glow Worm Flexicom CX30 boiler fitted some four years ago by a corgi reg chap. All was fine for about a year then started going wrong with leaks in floor (concrete floor). Identifed leaks and got them fixed. Both on joints which had not been protected when house was built (so not fault of plumber). But recently I have looked at the boiler detailing and it looks to me as though it has been fitted the wrong way round i.e flow and return. Plumber stated that it did not matter! Seems to me it does but I am no expert. To cut a long story short its loosing pressure again and I am having to top it up each day. Struggling to find any leak (borrowed a thermal imaging camera...could see nothing obvious but then again I suppose it could be leaking below pipe and perhaps for this reason it would not show up?). There is a small amount of water from the safety valve pipe outside but does not look enough for the amount I keep having to top up. Has anyone any thoghts ideas which might help please?