In article ,
bobmct wrote:

I have one of these contraptions and I change the filter element every
1-2 months depending on conditions.

Usually, with the Omni wrench, its simply a matter of unscrewing and
spinning the filter holder off, replacing the element and rescrewing
it back on.

However, for the past few months its a herculean effort to unscrew the
filter holder. I must brace the entry and exit pipes and really put
some muscle into it. So much in fact that I'm afraid of breaking it.

I've inspected the inside of the device and it all looks normal and
there is no goop around the threads or anything.

Does anyone have any ideas or suggestions as to why this might be
doing this and, more importantly, what I might be able to do to
relieve this situation?

Thanks all.

Chase the threads. Probably got dinged up or cross-threaded at some
point.