Where would my filter be on my (heil) furnace is within a filter?

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Answers:    Yes there should be a filter. If you don't see a cover surrounded by the duct work coming into the furnace approximately 2 inches wide consequently there is a couple other places to look. Inside the furnace, if it is a down-flow, the filter will be above the blower. If it is an up-flow after it will be below the blower. If there is no filter near it is possible you have one within the return air grill.
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