Quick take
Use gravity drain when you have a reliable downhill path to an approved drain. Use a condensate pump when water must travel upward or across a flat route.
Gravity drain is simpler
A gravity hose has no pump to fail and uses no extra electricity. The line must maintain continuous downward slope and avoid traps that hold water.
When a pump is necessary
Basements and crawlspaces often lack a lower drain. A condensate pump can lift water to a sink, standpipe or other approved discharge point.
Plan for clogs and freezing
Drain lines can collect slime, debris or freeze in cold spaces. Route them where they can be inspected and cleaned.
Match the dehumidifier to the installation
AlorAir, Argendon and similar crawlspace dehumidifiers often support continuous drainage, while some models add built-in pump options.