Tony wrote:

What sort of maintenance does a whole house UV treatment unit need? This
is the type that comprises a sealed stainless steel tube about 1.5m long
within which there is UV fluorescent light? Does the UV light need to be
replaced regularly (in fact, short of doing a water quality test, I
guess I don't know that it is actually working!)
thanks

We have one as part of an 8 stage water treatment system. They are
pretty worthless on their own.

--
Grunff