Covec Brittony 2T proving only luke warm water at the highest setting

[Willam]

I have an old Corvec Brittony 2T water heater and the problem is it only provides lukewarm water. The rubber gaskets were replaced about 18 months ago and I live in a hard water area. I suspect that the heater exchanger is getting furred up and needs replacing. Would be better to replace it altogether by another water heater? Could you suggest another one which would not involve too much wall alterations for the new flue. Many thanks

 

[ShaunCorbs]

Would say you need to address the hard water issue first but might be worth getting a gas safe engy out to have a look