ransley wrote:
....
They make more money replacing units, you got a dishonest tech.

Maybe, but certainly not necessarily.

Symptom can be sign of exchanger leak. I would have expected them to
have lit and done some testing for combustion gases first, though.

Certainly you'll want a second or even third opinion/bid before
committing. In LA area wouldn't think enough of a heat load that
efficiency on that side would matter terribly much but A/C upgrade could
potentially pay for itself relatively short order depending on what
efficiency it is.

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