MERV stands for Minimum Efficiency Reporting Value. Air filters are measured by the MERV rating, the higher the rating the more contaminants the filter can capture.

If you don’t already have a filter in your air return or there isn’t a size printed on your current filter, please measure the space for accuracy. We will need height X width X depth.

Standard Sizes:

The industry standard is for HVAC filter sizes on the frame to be printed in whole numbers or “nominal” sizes with the fractional or “actual” size next to it in small print.  The actual size might be a nominal size that we have in stock, or it might be a special size that we will have to make.

Nominal Size: 14x20x1 Nominal Size: 13 ½ “ x 19 ½ “ x ¾ “→   Click for nominal vs exact document.

Special Sizes:

There is no industry standard for nominal/actual size. Special sizes are made per the measurements you provide.

If you ordered a special size that we had to make, then the printed size on the filter is no longer valid. If you see tape or modifications to your filter and your sales order says cut/cap, we had to modify a standard size(s). The size printed was the standard size filter that we used to custom-make your special size. Please take the following steps before bringing it back:

1. Check all 4 sides of the filter for a handwritten size or sticker
2. Measure the filter
3. Compare the measurement to the sales order
4. Call the office to confirm

We recommend you use the same MERV-rated filter that came with the unit. Consult your air conditioning company about using a higher MERV-rated filter in your unit.