HVAC air filter product attributes

Air filters look like the simplest item in an HVAC catalog, yet they generate a steady stream of mismatches. The size printed on the frame is a nominal label, while the filter itself is usually about half an inch smaller in width and height and slightly thinner than its nominal depth. Supplier files often carry only one of the two, and it is not always clear which one they mean.

Efficiency ratings are the second problem. MERV comes from ASHRAE 52.2, ISO 16890 uses a different test and reporting scheme, and several retailers and brands publish their own scales. None of these convert cleanly into each other, so a record that stores a single efficiency number without naming its test method cannot be compared across suppliers.

Performance values only mean something alongside the conditions they were measured at. Airflow, initial resistance and dust holding capacity all depend on face velocity. Pack quantity matters just as much: filters are often priced per case but ordered per each, and a missing case count turns a routine reorder into a pricing error.

The air filters attribute template

18 candidate fields in 5 groups, ordered the way a record gets built: identify the item, capture its specifications, then record fit and the evidence behind any claim. 10 are marked Core: without them the item cannot be identified or filtered. Example values show the expected format only; they do not describe a real SKU.

Identity

Which exact item, variant and pack this record describes.

Check before use: Preserve leading zeros and punctuation, validate against the manufacturer record, and check the GTIN check digit and packaging level before linking.

Attribute	Type	Priority	Example format
Manufacturer Part Number manufacturer_part_number	Identifier	Core	PF-20251-M10
GTIN / UPC gtin_upc	Identifier	Core	012345202513
Pack Quantity (Filters per Case) pack_quantity_filters_per_case	Number	Core	12

Technical specifications

Measured or rated values that must travel with their unit and test conditions.

Check before use: Store the number and unit separately. Convert only when the source unit and test conditions are known.

Attribute	Type	Priority	Example format
Actual Filter Size (W x H x D) actual_filter_size_w_x_h_x_d	Text · in	Core	19-1/2 x 24-1/2 x 7/8
MERV Rating merv_rating	Number	Core	10
Rated Airflow rated_airflow	Number · CFM	Buyer decision	1,040 CFM at 300 fpm
Initial Resistance initial_resistance	Number · in w.g.	Buyer decision	0.21 in w.g. at 300 fpm
Recommended Final Resistance recommended_final_resistance	Number · in w.g.	Buyer decision	1.0 in w.g.
Dust Holding Capacity dust_holding_capacity	Number · g	Buyer decision	45 g at 300 fpm (ASHRAE 52.2 loading dust)
Effective Media Area effective_media_area	Number · ft²	Buyer decision	5.2 ft²

Selection attributes

The type, material and option choices buyers filter and compare on.

Check before use: Map supplier wording to a governed vocabulary only after checking the source text and which variant it applies to.

Attribute	Type	Priority	Example format
Filter Type filter_type	Controlled list	Core	Pleated panel
Media Type media_type	Controlled list	Core	Synthetic electret
Frame Material frame_material	Controlled list	Core	Coated beverage board

Fit & compatibility

What the item mounts to, mates with, replaces or works alongside.

Check before use: Keep model and series qualifiers. A similar-looking part is not a verified fit until a source says so.

Attribute	Type	Priority	Example format
Nominal Filter Size (W x H x D) nominal_filter_size_w_x_h_x_d	Text · in	Core	20 x 25 x 1
Equipment Cross-Reference equipment_cross_reference	Text	Buyer decision	Replaces OEM filter FLT-2025-OEM in listed furnace models

Evidence & compliance

Listings, standards, classifications and origin claims that need a document behind them.

Check before use: Link the manufacturer document or label with its edition or date. Never copy a certification from a neighboring SKU.

Attribute	Type	Priority	Example format
Country of Origin country_of_origin	Controlled list	Core	United States
UL 900 Classification ul_900_classification	Controlled list	Channel / evidence	UL 900 Classified
ISO 16890 Class iso_16890_class	Controlled list	Channel / evidence	ISO ePM10 50%

Normalize supplier values

The same value arrives in many spellings. Map each raw string to one governed value, and keep the raw text beside it so a reviewer can see what the supplier actually wrote.

Often missing from supplier files

These fields are commonly absent from price lists and basic feeds, even though the information usually exists in a datasheet, label or installation manual. Treat an empty value as a request for evidence, not as permission to fill it from a similar model.

• Actual filter size (W x H x D)
• MERV-A (ASHRAE 52.2 Appendix J) value
• Face velocity behind the airflow and resistance figures
• Selling unit of measure vs case quantity
• OEM or equipment cross-reference

Questions the record must answer

Buyers and counter-sales reps choosing air filters ask questions like these. Each one needs a specific field, sourced for the exact variant.

• The grille says 20x25x1 but my old filter measures 19-1/2 by 24-1/2. Is this the right one?
• Will a MERV 13 filter restrict airflow too much on my system?
• How many filters are in a case, and can I buy them individually?
• Does this replace the filter my furnace manufacturer specifies?

From supplier file to record

1. Resolve identity first. Link the supplier SKU, manufacturer part number and packaging identifiers without merging distinct variants or pack sizes.
2. Extract with the source attached. Pull values from rows, tables and datasheets, keeping the raw text, unit and page or row reference.
3. Map to your classification. Assign the ETIM, ECLASS, UNSPSC or internal class your company licenses, and keep the supplier's original terms.
4. Review, sync and watch. Hold conflicts and safety-related values for a category expert, write approved values to ERP or PIM, and recheck when the supplier sends a new file.

For the full method, see how to build a category attribute template and the category catalog gap audit.

FAQ