What if you don't change your air filter in your furnace?

Just moved into a house a month ago(rented) I just checked the air filter in the furnace and it honestly looks like it hasnt been changed in 3 years. It's completely black and thick with dust and whatever else. I changed the fliter today but what effects could this have had on my health if I didn't change it and lived with a competely dirty air filted for a year?
What if you don't change your air filter in your furnace?
You would have restricted air flow. If you have air conditioning this could cause your evaporator coils to freeze up.As`far as health concerns it seems a clean filter is healthier than a dirty one.
What if you don't change your air filter in your furnace?
nothing on your health, but it would have made the furnace work way to hard and probably constantly. the filter is there to help the furnace run efficient and for the life of it to be longer. has nothing to do with your health.it only affects people with allergies. with no filter, alot of dust will go through the house. but not much else.
pay someone to clean the coil it is most likely dirty too. a dirty coil will make your a/c work to hard this summer.

vc

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