Blog
HEPA vs MERV 13: Which Actually Filters Better (and Why Your Ducts Get a Vote)
On pure capture efficiency, HEPA wins outright — 99.97% of particles at 0.3 microns and above, versus MERV 13's ≥50% in its hardest sub...
Filtrete MPR Decoded: the 300–2800 Series, and Its Honest MERV Conversions
MPR (Micro Particle Performance Rating) is 3M's private scale for Filtrete filters, measuring capture of 0.3–1.0 micron particles — the...
Why Is My Furnace Filter Black? Soot vs. Mold vs. Bypass (the Three-Way Diagnosis)
A black furnace filter means one of three things, and the pattern of the black picks which: an even, sooty gray-black across the whole ...
Furnace Filter Replacement Cost: What You Should Actually Pay in 2026 (Per Tier, Per Year, Per Technician)
The filter itself costs $2 to $45 depending on tier — fiberglass $2–5, MERV 8 pleated $8–15, MERV 11 $10–20, MERV 13 $15–25, and 4″ med...
Where Is My Furnace Filter? Location by System Type and Brand (Five Places, One Checklist)
Your furnace filter is in one of five places, and the system type picks it: a return-air wall grille (the big vent that sucks — check t...
Does Medicare Cover CPAP Supplies? The Coverage Path, the Timelines, and What’s Left to Pay
Yes — Medicare Part B covers CPAP therapy and its replacement supplies as durable medical equipment (DME) when three conditions hold: a...
AirSense 11 vs AirCurve 11 vs AirMini: Three Machines for Three Prescriptions (With the Supplies Matrix)
These three ResMed machines are not three price tiers of the same therapy — they're three different device classes, and which one you u...
Furnace Filter Sizes: the Complete Chart, and Why the Number on the Box Is a Lie By Half an Inch
The size printed on a furnace filter box is a nominal dimension — the actual cartridge is smaller by roughly ¼ to ¾ of an inch on every...
AirSense 11 Troubleshooting: Symbols, Startup Failures, Bluetooth, and When It’s a Provider Call
AirSense 11 problems sort into four families, and the fix depends on which one you're in: settings-and-symbols (the flashing snowflake,...
When to Replace Every CPAP Supply: The Full Schedule Table (With the Adherence Data Behind It)
ResMed's replacement schedule runs on three clocks: check mask cushions/pillows and the machine air filter monthly, replace mask frame ...