My fan on my heating and air unit hs started making a very loud grinding noise like it is about to break. What would cause this and can it be fixed? Had problem before in summer and a guy came out to fix, said that it wasn't a good unit and the fan was flimsy and not of good quality. Will I have to get a new unit?

I wouldn`t think the entire unit needs replaced, Most any part can be replaced as good as or better than new
Could be the blades in the fan,or the,motor,, but you do need to get it looked at or look at it yourself ,determine exactly where the noise is coming from

I had the same problem and replacing the Inducer Motor Assembly (about $120) took care of that. Mine is a Goodman GMS8 series. Part under warranty for 5 yrs. Heat exchange for 20 yrs. My Motor was squeeling loud. Also check the pressure switch (about $35).

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