Question: How do I choose a furnace filter for my HVAC system?
Answer: Always check with your HVAC technician prior to replacing your furnace filter. He or she is knowledgable about the air duct capacity and motor capacity of your system. Another option is to match the furnace filter in your system with another that is the same MERV rating or MPR (Microparticle Performance Rating). Explain that the 1 inch filter has an internal frame, that no air can go around it. Similarly the 4 inch thick unit is made to fit a 4 or 5 inch filter slot.
The buyer of a furnace filter must assume responsibility for his or her choice of furnace filters. No on-line company nor box store knows the age, the air duct capacity, the motor capacity, etc. of your HVAC system. Only your HVAC technician is qualified to determine the density of a filter that will work in your furnace and cause no problems.
Safe Home internal frame filters have two layers of media. The white side must be inserted into the filter panel so that the air flow goes through that part first. With the internal metal frame, this filter fits very tightly into the opening. No air can go around it. Your HVAC technician needs to know that this is an internal frame filter with no air escaping around it.
The Safe Home Duo 4 filters are also made to fit very tightly in the filter holder. This unit is also marked so it must be installed so that the air flow goes through the filter in the correct direction. Again it is important that your HVAC technician be aware of this tight fit. These units replace 4 or 5 inch thick filters. Always insert so that airflow goes first through the white side.
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