Aprilaire 213 Filter Replacement Steps
Aprilaire media cabinets use numbered filters — 213 is one of the most common. Replacing it takes a few minutes, but orientation and door latch sealing matter for filtration performance.
Updated July 2026 · 4 min read · Canada
Symptoms
- Dust on furniture despite running the system
- Media looks gray/black past the 6–12 month mark
- Door label shows filter #213
Likely causes
- Expired media
- Filter installed with airflow arrow reversed
- Door not fully latched after the last change
What to do
1. Turn the system fan off
Set the thermostat fan to Auto/Off so air is not blowing when you open the cabinet.
2. Open the Aprilaire door and slide media out
Release the door latches, pull the inner rail/media assembly, and remove the dirty expandable media.
3. Expand the new 213 and align the arrow
Expand the replacement fully in the rail. Airflow arrow should point toward the blower / with the cabinet’s embossed arrow.
4. Reseat the door and log the date
Latch firmly. Mark the install month on the door sticker — Aprilaire typically recommends annual changes (sooner with pets/construction).
Stop and call a pro when
- The cabinet door is warped and will not seal
- You also have an Aprilaire humidifier sharing the plenum and see water leaks
Related guides
- Filter Size Guide — How to read furnace filter dimensions, why nominal vs. actual sizes differ, and which MERV rating to buy without starving airflow.
- Aprilaire 201 Replacement — Replace Aprilaire filter #201 in compatible air cleaners — orientation, intervals, and how it differs from 213/216.
- Aprilaire 216 Replacement — How to replace Aprilaire 216 media in 1210/2210/3210/4210-series cleaners with correct orientation and buy links.
- Replace 16×25×1 Filter — Quick homeowner steps to change a 16x25x1 furnace or air handler filter, plus MERV guidance and multipack links.
- Replace 20×25×5 Media — Replace a 20x25x5 thick media filter used in many Honeywell/Resideo-style cabinets, with orientation and interval tips.
FAQ
Is Aprilaire 213 the same as 213b?
213b is the updated media formulation for the same cabinets. Either is typically acceptable when the door specifies 213 — confirm packaging compatibility.
Can I use a generic 213 filter?
Many third-party medias fit. Choose reputable MERV ratings and exact rail dimensions; a short filter leaves bypass gaps.
Need a licensed tech instead?
If the guide says to stop — or the part swap did not clear the fault — get free quotes from licensed local HVAC contractors.
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