Filter Replacement

Start with the part number

These parts are made for specific units, so the part number is the reliable match: for example Electro Air DM900-0810, Lennox X4138 or ECOairflow CMP-1000-1625. If there is no number on the old filter, look up your unit's model number in its manual.

What you will find here

• HEPA filters: Lennox 92X10 (HEPA-40 and HEPA-60) and 92X17 (HEPA 20), Electro Air W4-0840, Reversomatic 12x16x2-1/2.
• Carbon filters: Lennox X4137 and X4138 pre-filters, X2678 and 92X09 inner filters, the 94X98 carbon canister, Electro Air W5-0810 pleated carbon prefilter.
• PCO metal mesh inserts: Lennox X8791 (20x25x1), 75X66 (21x26x1) and Y6607.
• Charged media pads: ECOairflow CMP-1000, CMP-1500 and CMP-DYNA pads.

Replacement Filter FAQs

How often should I replace the filters in a whole-house air cleaner?

Replace whole-house air cleaner filters on the manufacturer's schedule, because intervals vary widely by part. For example, ECOairflow recommends changing Dynamo charged media pads every 3 months, GeneralAire says to replace the HEPA filter in its HEPA 400R once a year, and Amaircare says its VOC carbon canisters can last up to a year depending on pollution levels. Your unit's manual lists its exact intervals.

What is the difference between a HEPA filter and a MERV-rated filter?

A HEPA filter is a very high-efficiency filter that the EPA says is generally equivalent to MERV 16, the top of the MERV scale, which runs from 1 to 16 under ASHRAE Standard 52.2. Higher-efficiency media also restricts airflow more, so the EPA notes a filter upgrade must suit the existing ducted system. Replace HEPA filters with the part made for your unit rather than a MERV filter.

Why should I replace a carbon filter if it still looks clean?

Replace a carbon filter on schedule even if it looks clean, because carbon removes odours and gases by adsorption and has a finite capacity you cannot see. The EPA says adsorbent filters need regular replacement to avoid breakthrough, and that thin carbon layers saturate quickly. Amaircare, for example, says its VOC carbon canisters can last up to a year, depending on how much pollution they handle.

What does a PCO metal mesh insert do in an air purifier?

A PCO (photocatalytic oxidation) metal mesh insert is a high-surface-area medium coated with a catalyst, such as titanium dioxide, that adsorbs gaseous pollutants so they can be oxidized, ideally into carbon dioxide and water. The EPA notes removal varies widely between gases. Lennox PCO inserts are sold by part number and size, such as X8791 (20 x 25 x 1) and 75X66 (21 x 26 x 1).

How do I choose replacement charged media pads?

Choose replacement charged media pads by matching both the series and the size of your current pads. ECOairflow part numbers combine the series, such as CMP-1000, CMP-1500 or CMP-DYNA, with the frame size, so CMP-1000-2025 is a 20 x 25 x 1 inch pad. ECOairflow says its Dynamo pad is a single piece that swaps in under a minute without tools.

What should I do if my replacement filter part number has been superseded?

If a replacement filter part number has been superseded, order the newer part number listed as its replacement. PureFilters titles show this with 'Replaces', for example the Lifebreath 65-299R MERV 8 TFP collector, which replaces 65-503R. If you can't find your number, email it to support@purefilters.ca for part-finding help.