NO.... As vaillant know the filter was not fitted correctly . And have noted it in their records As they cannot be sure of any damage or wear . Imagine a car company had a owner who drained the original oil from their new car on day one and put nasty inferior wrong spec oil in for 2 years . And then the owner says, "well if i put the right stuff in ,does the warrantee still hold" ? !!!! NO WAY it would . Warrantees stipulate terms and conditions for a given reason . And the so called "engineer " was so bold to say he does it often and so do many others within the "company ". I always think , those people that see it differently would soon change tunes if it was their money spent in good faith !