How Your Home Breathes
Plain-English facts about heating, cooling, filters, air ducts and indoor air, checked against the EPA, the Department of Energy, ASHRAE and NADCA.
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22 deep dives
Clear Air Cleaning explains the machines and air paths inside a home: how heating and cooling work, what filters really catch, what is inside your ducts and what the science says about cleaning them. Facts only, sourced from the EPA, DOE, ASHRAE and NADCA, with no sales pitch.
How a Home HVAC System Works
Heat, cool, move and clean the air
The Refrigeration Cycle
How air conditioners move heat outside
How Heat Pumps Work
One machine that heats and cools
How Furnaces Work
Burners, heat exchangers and AFUE ratings
Ductless Mini-Splits
Heating and cooling without ductwork
MERV Ratings Explained
What the numbers on your filter mean
HEPA Filters
The 99.97 percent standard explained
Portable Air Cleaners
CADR, room size and the ozone warning
When to Change Your Air Filter
Check monthly, change at least every three months
How Air Ducts Work
Supply runs, returns and registers
Air Duct Cleaning: What the EPA Says
When it helps and what it cannot promise
Leaky Ducts and Duct Sealing
Where a quarter of your air can go
Indoor Air Quality Basics
What is in the air at home
Humidity and Mold at Home
Why 30 to 50 percent humidity is best
Ventilation and Fresh Air
Exhaust fans, ERVs and HRVs
Carbon Monoxide and Your Heating
The odorless gas every home should watch
Dryer Vent Fire Safety
Lint is the leading cause of dryer fires
Willis Carrier
The engineer behind modern air conditioning
Cooling Before Air Conditioning
Windcatchers, ice machines and window units
Refrigerants: From CFCs to Today
Why the fluid in your AC keeps changing
Thermostats and Smart Settings
Small settings, real savings
Seasonal HVAC Care Checklist
What homeowners can check each season
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