I have a 3 yr old heat pump furnace / air conditioner unit in a home I recently moved into. Just had the furnace serviced to assure all was OK, and it is. I have allergies, and asthma, and am allergic to mold and dust.
There is currently an inexpensive (fiberglass) air filter in the unit, and I want to put in a more expensive, higher Merv rating filter (rating =11). This is due to my allergies. Service man cautions me not to do it, since he indicates that it will put alot more strain on the unit, especially during heating season. He says the effect will be to greatly reduce the life of the unit.
What do you guys think about his cautions? If it is bad, why do places like Home Depot sell so many higher rated air filters, like the one I am considering using?