What is the MERV number on house air filters represent? Should

What is MERV?

@funacct :
I don't know- it's just something I see on Amazon on the filter options.

MERV is a rating system of the efficiency of HVAC air filters. There is also MPR and FPR used by different manufacturers.MERV (or MPR or FPR) measures how many particles and how small they are that are trapped by the filter. The higher the MERV number the smaller the particles that the filter can trap.However, the finer the particles the filter can filter down to the more restrictive it is to air flow. It is important to allow free airflow for the HVAC to work efficiently.MERV 7 or 8 for easier airflow for older HVAC systems. MERV 9 to 11 is a good balance. MERV 12 or higher is very restrictive and should only be used on systems designed for it. Check the HVAC label or the manual for recommendations.

@KiNg: so interesting. Sounds like you have to figure out a good balance. Yiu don't want to restrict the air too much because you make the AC unit work too hard. But you also want it to filter your air

@KiNg :
Thank you so much. That's exactly what I needed to know!

Don't forget to do a quick visual inspection of the outdoor condensing unit every once in a while. If it is covered in dust it should be hosed off.