I have a York Diamond 80:
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The book that came with my York Diamond 80 says to use a "High Velocity" filter. It says "Warning, when replacing the filter DO NOT use a type with excessively high pressure drop. Some high efficiency filters available will cause the furnace to operate improperly and could result in a safety hazard"The filter that came out of the unit looks like a scotch-brite pad that you would use to do the dishes. I cannot find a filter like this at Home Depot and I cannot find any filter rated as "High Velocity". Can I use a 3M Filtrete filter like this:
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This filter is not labeled as high velocity.