Had a think & I am back
slug of hot water when it is 1st turned on (when heating is on as well) tmv may be required ? scaling of 10mm hot water pipe in the heat exc block ?? maybe not so easy to de scale ?
Condensate corrosion on ally block & sump ? in particular those fitted to LPg early days in the UK market ? 5 year warranty pobably under written by D&G ( possibly ?) payed for at point of sale ?? maybe ??
slug of hot water Tony posted on this months back irrelevant.............
In all the years Ive worked in heating complaints about hot water in domestic nil not water not hot enough loads and it doesnt last long some people find that usefull ........true !!! theyr'e impressed and see it as fast !
Gloworm had a similar type boiler years ago , which caused an intial slug of hot water at high temp ect as I understand it they were sued over the affair I beleive there was a post in the CC a good while back about this think it was DM who brought this to my attention ??