4 components coveredField manual · Dehumidifier
Honeywell / Resideo TrueDRY DR65 and DR90 whole-house ventilating dehumidifiers: quick sheet
Covers: TrueDRY DR65 (DR65A1000, DR65A2000) and DR90 (DR90A1000, DR90A2000) ducted whole-house dehumidifiers sold through HVAC distributors, mostly 2010s installs. Discontinued; parts support varies. Figures below are from the A2000 spec data sheets unless noted.
Ducted, R-410A whole-house dehumidifiers with an onboard dehumidistat (they can run with no external control), 24 V terminals for remote controls, a float-switch input and a ventilation option. Service calls are drain blockage and float trips, dirty MERV-11 filters, compressor-start parts, low-ambient defrost cycling and duct setup (missing backdraft damper).
Safety first
- Unplug before opening the cabinet.
- R-410A sealed-system work is for an EPA 608 certified technician: diagnosis and referral only.
How it works
Refrigerated coil cools incoming air below its dew point; water drains off the coil and the drier, slightly warmer air goes back to the house.
An onboard dehumidistat lets the unit run on its own; 24 V wired or wireless remote controls can also run it. A 40 VA, 120/24 V transformer powers the relays and supplies 24 VAC to the R/C terminals.
A 24 V normally closed float switch or water sensor in a drain pan can be wired in to kill the compressor if the drain blocks.
Ventilation: the blower can bring in outdoor air through a motorized damper on a separate control, even when no drying is needed (DR90 has a 6 in supply-side inlet for this).
Ducting options in the spec sheet: dedicated return to main supply, main return to main supply, dedicated return to main return, main return to main return, or stand-alone (not tied to the HVAC). When tied to the AC supply, a backdraft damper on the dehumidifier outlet stops air from being pushed back through it when the AC runs alone.
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Always confirm values against the tech sheet for the exact model.
OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Vertical pressure tank connected to a water pump outdoors by W.carter, CC BY-SA 4.0
