Video · HVAC Installation Craft
AC Filter Drier Install: Copper, a Torch and a Wet Rag
An AC filter drier traps moisture and debris before they can damage the system, and it should be replaced whenever the refrigerant circuit is opened. Here a tech brazes a new one in at the condenser.
Job footageSwiftPro
- Topic
- HVAC Installation Craft
- Length
- 0:31
- Posted
- August 17, 2026
- Shot by
- The SwiftPro crew, Northern Virginia
What you’re seeing in this video
A tech in a backward trucker cap and hoodie brazes copper at an outdoor condenser with its top opened, a red rag draped over the coil to shield the aluminum fins from the flame.
Beside the house, another tech handles a pink refrigerant cylinder next to the unit. In the close-up, the torch flows filler onto a joint at the service valve, which is wrapped in a wet rag so the heat doesn't damage the valve. The filter drier is the small canister in the liquid line, the thinner of the two copper pipes.
Why it matters in your house
- Moisture in a refrigerant system turns into acid that eats at the compressor windings. A fresh filter drier soaks it up and catches debris left from brazing or a burnout.
- If a tech opens your system for a repair and doesn't change the drier, ask why. It's a small part protecting the most expensive one.
- Filter driers carry a flow arrow, and a careful installer checks it before brazing. Heat pumps use a bi-flow drier because refrigerant runs both directions.
What does a filter drier do in an AC system?
It's a small canister in the liquid line that holds a drying material and a screen. The drying material absorbs moisture and the screen catches debris so neither reaches the metering device or compressor. It's replaced any time the sealed system is opened, because once it's exposed to air it starts soaking up moisture.
Want it done at your place? See HVAC Installation Craft at SwiftPro or call (703) 997-9757.
More videos from the SwiftPro crew
0:46Sealing Ductwork Connections, With the Sound Turned Up
0:27HVAC Plenum Up Close: Checking Seams and Sealing Around the Coil
1:23R-454B Refrigerant Install on a Long Line Set, With a Job Site Check-In
0:46Brazing an AC Line Set: The Torch Work on an AC Swap
0:31Brazing vs Soldering: Why Refrigerant Lines Get Brazed
0:38Duct Transition: How a Wider New Furnace Meets the Old Ductwork