Latest guide
Cleaning a mini split indoor unit: what to spray, what to skip
Musty smell, weak airflow, black specks on the louvers? A wall-mounted head needs more than a filter rinse. Here's the full routine, start to finish.
Easy45 minutes
More guides
Why your heat pump steams in winter and when it's a real problem
Clouds of steam, a whoosh, and the fan quits. Looks broken. Usually it's just the defrost cycle doing what it's supposed to do.
Easy10 minutes
Thermostat wire colors don't mean what you think
R, C, W, Y, G, O/B. What each letter actually does, why you can't trust the colors, and the one photo that'll save your butt before you disconnect anything.
Moderate30 minutes
Clearing a clogged AC condensate drain line
AC quit and won't come back on? Water sitting in the pan under your furnace? A clogged drain is the culprit behind a ton of summer service calls, and it's usually a quick fix you can handle yourself.
Easy30 minutes
Testing an AC capacitor with a multimeter
Outdoor unit humming but the fan won't spin? A bad run capacitor is one of the most common culprits, and one of the cheapest parts in the whole system. Here's how to check it without getting hurt.
Moderate45 minutes
MERV ratings: what filter your furnace can actually handle
MERV 8, 11, 13. Higher catches more junk, but jam in too dense a filter and your airflow pays the price. Here's how to choose without getting lost in the aisle.
Easy10 minutes
Pulling a vacuum on a mini split line set: what actually works
Rushing the vacuum kills mini splits early. Here's what a micron gauge actually tells you, what "good" looks like, and how to read a decay test without guessing.
Advanced1 to 2 hours
The DIY HVAC tool kit: what's actually worth buying
You don't need a service van full of gear. Here's what a homeowner really uses, in the order you'll need it, from swapping filters all the way up to installing a mini split.
EasyA weekend of shopping
AC's running but not cooling? Try these 8 checks first
Before you pick up the phone, walk through this list. A bunch of common causes won't cost you a dime to fix, and the rest give you something useful to tell the tech.
Easy30 minutes