Quest 506 Duct Kit 4038641 | 12 in Collars, First Gen 506 and 277V

Which Side the Exhaust Duct Kit Actually Fits

Part 4038641 is the exhaust kit, and the intake kit is a different part number. Quest publish two separate accessories for this unit: an exhaust kit as part 4038641, and an intake kit under a different part number entirely. Ordering by machine name alone is how people end up with the wrong side. Quest list compatibility narrowly, naming the first generation 506 and the 506 277V specifically. Check the unit's own part number before ordering, because a later generation 506 is not covered. The kit itself is two pieces plus fixings: a duct adapter, a collar plate and screws. The collar plate carries 12 in round collars, and the kit measures 27.57 in by 21.5 in by 4 in. What it buys you is the ability to put the dehumidifier outside the canopy space entirely. That takes the compressor heat, the noise and the footprint out of the room while the air still gets dried.

Static Pressure, Duct Runs and the Numbers Quest Publish

Static pressure is the limit that decides whether a ducted install works or quietly underperforms. Quest state that it must not exceed a quarter of an inch water gauge on this unit. They also specify a minimum of two twelve inch round ducts when either side is ducted, not one larger one. And they require at least 4 ft of straight duct off the unit before any turn, which is the rule most installs break first. The 506 moves 1500 CFM at zero static on the 230 volt machine and 1350 CFM on the 277 volt version. Every elbow, every foot of flex and every grille eats into that, and flex duct costs far more pressure than rigid. Size the run to the pressure budget first and to the convenient route second. A unit fighting its ducting pulls the same power and removes less water, which shows up as a room that never quite dries. Nothing on the machine warns you about it either. Spend the extra on rigid duct and two clean bends and the accessory earns its money.

Key Features

• Which side: Exhaust, as part 4038641
• The other side: Quest list the intake kit under its own part number
• Fits: First generation Quest 506 and 506 277V
• Contents: Duct adapter, collar plate and screws
• Collars: 12 in round, two of them
• Kit size: 27.57 in by 21.5 in by 4 in
• Why duct it: Puts the dehumidifier outside the canopy space
• Pressure limit: A quarter of an inch water gauge, per Quest
• Duct rule: Two twelve inch round ducts, and 4 ft straight before a turn
• Unit airflow: 1500 CFM at zero static on the 230 volt model

Technical Specifications