Have been advised by original installing company (who have serviced each year) of potential problems with rubber hoses in this boiler now almost 5 years old. It seems installing company gave me a 5 year warranty (which apparently is NOT registered with Vaillant) but will not replace the hoses free of charge. Installing company want to charge me between £220-£300 to replace rubber hoses for copper hoses. Vaillant won't be responsible for anything as say the boiler not registered with them (have not yet asked installing company why not) but have advised me that this estimate is excessively high. Have spent time searching various plumbing forums so know that (since at least 2010) there have been many problems with these hoses splitting and can totally ruin the boiler. Obviously I need to replace the hoses as cannot afford for these hoses to split but need realistic costing. 2 plumbing companies want to look at boiler before estimating (?), 1 said he thought I should get Vaillant to replace them (at least they would be cheaper if they think current estimate is excessive!). Heating parts company estimate copper hoses would be about £80. Has anyone had similar problems - can anyone give me any advice before I go any further?