THE COMPLETE FIELD MANUAL
Diagnose the building.
Then choose the machine.
Fourteen independent field notes organized around the decision: find the source, define the load, install for reality and verify the result.
DIAGNOSE
Find the load before the machine
What humidity should a crawl space be?
Read the trend, verify the sensor and know when persistent humidity needs investigation.
Read field note →02Why humidity stays high while the unit runs
Troubleshoot source, boundary, airflow, temperature, drainage and capacity in order.
Read field note →03When a dehumidifier is not enough
Recognize water-damage conditions that need a different first move.
Read field note →04Vapor barrier before a dehumidifier?
Control soil vapor and liquid water before sizing residual humidity control.
Read field note →SIZE & COMPARE
Turn conditions into specifications
Dehumidifier size chart by square feet
Use area as a starting band, then correct for severity, leakage and temperature.
Read field note →02How to size a crawl-space dehumidifier
A complete sizing method based on moisture load—not box-front coverage.
Read field note →03AHAM pints vs. saturation pints
Compare like-for-like capacity numbers under meaningful test conditions.
Read field note →04What a crawl-space dehumidifier costs to run
Estimate electricity from watts, runtime, efficiency and your utility rate.
Read field note →05Low-temperature operation and defrost
Understand cold-weather collection, icing and automatic defrost limits.
Read field note →INSTALL & VERIFY
Make the equipment work in the building
Where a crawl-space dehumidifier should go
Balance representative air, circulation, drainage, power and service access.
Read field note →02Ducted vs. standalone dehumidifiers
Use ducting to solve measured distribution problems without choking airflow.
Read field note →03Pump or gravity drain?
Choose a permanent condensate route before choosing the unit.
Read field note →04How long should a dehumidifier run?
Separate initial stabilization from steady-state humidity control.
Read field note →05Dehumidifier vs. encapsulation
Understand the separate jobs of source reduction and vapor removal.
Read field note →