Quest 335 Duct Kit

What the Quest 335 Duct Kit Includes

This factory accessory converts a Quest 335 from a free-hanging unit into a ducted dehumidifier. The kit connects both airflow paths, with an intake adapter on the return side and a plenum on the discharge side. In the box are an intake duct adapter, a duct adapter face, a duct plenum face and an exhaust duct plenum. Ten #10-24 hex-slotted screws and a 1/8 in drill bit come with it for fastening the parts to the cabinet. Both connections take 16 in round duct. Quest part number 4042685 fits the Quest 335 at 208/230 V (4042500) and at 277 V (4042600). It also fits the 50 Hz Quest 375 (4046200-NC). The 335 moves 900 CFM at 0.6 in WG with duct collars fitted, so the blower has pressure to spare for a short run. That lets the dehumidifier sit in a mechanical room or above a ceiling while dry air still reaches the canopy. Quest backs the kit with a 1-year limited warranty.

Planning a Run With a Dehumidifier Duct Kit

A dehumidifier duct kit makes sense when room space is tight, or when the unit's noise and heat belong somewhere else. Give each dehumidifier its own duct system rather than tying it into a fan or HVAC line. Keep each run to about 25 ft and as straight as possible, since every elbow adds resistance. Rigid pipe on a direct path holds airflow better than flex duct routed around obstacles. Drill only within the safe zones shown in the Quest 335 manual so screws stay clear of coils and wiring. Pull the return air from the warm, humid upper part of the room, where moisture collects late in flower. Aim the discharge across the canopy or into a circulation path so dry air mixes instead of pooling. Seal every joint with foil tape to stop the unit pulling in air from the plenum space. Leave room to reach the end access panel, because the 22 x 20 x 2 in MERV-13 filter still needs regular changes. Installed this way, the 335 keeps its rated capacity while staying out of the growing space.

Key Features

• 16 in connections: Round duct on both intake and discharge.
• Complete hardware: Adapters, plenum, screws and drill bit included.
• Factory fit: Quest part 4042685 for the Quest 335 cabinet.
• Remote mounting: Run the unit from a mechanical room or ceiling.
• Supply and return: Ducts both airflow paths, not just discharge.

Technical Specifications