Image of the The Quest 746 480V featuring high capacity, 730 pints/day, 8.3 pints/kWh efficiency, multi-coil tech, digital controls, low amp draw, and compact design.

Quest 746 480V High-Capacity Dehumidifier - 730 Pints/Day

Q: What size dehumidifier do I need for my grow setup?

It depends on your grow tent or room size and how much moisture you need to pull. A 30-pint unit is great for small setups, while 50+ pint models work better for larger spaces. If you're running a big operation, go for a high-capacity unit with a built-in humidistat for full control.

by Quest

$12,999.95 - $12,999.95

$12,999.95

$12,999.95 - $12,999.95

$12,999.95

Qualifies for multi unit discounts

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Full Manufacturer’s Warranty

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Quest 746 removes 730 pints per day with M-CoRR tech and MERV 13 filtration, providing efficient, clean, and reliable humidity control for large-scale grow rooms.

A high efficiency 480V commercial dehumidifier delivering massive moisture removal lower energy costs and compact installation for demanding controlled environments.

The Quest 746 480V is built for facilities where moisture control is mission-critical and electrical capacity is always under pressure. Engineered with Quest’s patented M CoRR™ multi-coil technology, this commercial dehumidifier reuses energy during operation, delivering extreme moisture removal with industry-leading efficiency. It is designed to outperform traditional industrial units while occupying less space and drawing less amperage.

With ~730 pints per day of moisture removal at 80°F and 60% RH and an efficiency rating of 8.3 pints per kWh, the Quest 746 dramatically lowers operating costs in large scale grow rooms, processing areas, mechanical rooms, and controlled environments. The 480V design frees up panel capacity for lighting and HVAC, while the reduced height allows installation where other high-capacity units simply do not fit.

Features

M CoRR multi-coil technology reuses energy during dehumidification for maximum efficiency.
High capacity moisture removal delivers ~730 pints per day for large scale environments.
480V low amperage operation reduces electrical load and frees up panel space.
Compact low-profile design fits in mechanical rooms and tight overhead installations.
Integrated digital control panel allows precise humidity management with modern diagnostics.
Smart maintenance alerts include filter change, defrost notifications, and self diagnostics.
Dark Mode display reduces light output in sensitive environments.
External control ready with a low-voltage terminal block for automation integration.
Environmentally responsible refrigerant uses R454B with significantly lower GWP.
Engineered and assembled in Madison, WI, with a 5-year manufacturer's warranty.

What's Included?

Quest 746 480V Dehumidifier

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Specifications

SKU: QUE4046320

MFG #: 4046320

Test Conditions: 80°F at 60 percent relative humidity

Water Removal: 730 pints per day

Efficiency: 8.3 pints per kilowatt hour

Energy Factor: 3.9 liters per kilowatt hour

Current Draw: 4.9 amps

Power Consumption: 3,665 watts

Total Heat Load: 45,700 BTU

Heat of Condensation: 33,200 BTU

Motor Load Heat: 12,500 BTU

Test Conditions: 75°F at 50 percent relative humidity

Water Removal: 480 pints per day

Efficiency: 6.1 pints per kilowatt hour

Energy Factor: 2.9 liters per kilowatt hour

Current Draw: 4.6 amps

California Compliance: Title 24 compliant

Ducted Energy Factor: 7.7 pints per kilowatt hour at 73°F and 60 percent relative humidity

Part Number: 4046320

Dehumidifier Type: Refrigerant dehumidifier

Airflow: 1,650 CFM

Operating Temperature Range: 56°F minimum to 95°F maximum

Supply Voltage: 480V, 3 phase

Unit Dimensions: 44.8 in length x 28.9 in width x 27.4 in height

Unit Weight: 300 lb

Control Type: Onboard digital control with optional external control connection

Air Filter Rating: MERV 13

Air Filter Dimensions: 18 in x 20 in x 2 in

Power Connection: Hardwire only

Refrigerant Type: R454B

Refrigerant Charge: 6 lb 8 oz

Drain Port Connection: 3/4 in threaded NPT

Warranty: 5 year limited

Storage cabinet featuring dual doors and raised corner supports

Freestanding Unit

The Quest 746 Dehumidifier must be installed indoors in a dry, flood-protected space. Place it on a stable, level surface with clearance for maintenance and ensure air intake and exhaust remain unobstructed with at least 1 foot of clearance. The unit should not be used as a bench or table and must be placed with vibration isolation to reduce operational noise.

Isometric illustration of an industrial cabinet mounted overhead using suspension rods

Overhead Dehumidifier

The unit can be mounted overhead using 3/8" threaded rods attached to structural supports but must not be placed directly on structural members without proper vibration isolation. If installed above an area where leaks could cause damage, a drain pan must be used. Never allow the unit to be positioned where it could fall into water or discharge air directly at people or over a pool.

Drain trap diagram highlighting vented section and water seal depth

P-Trap Requirements

A P-trap with a 2-inch water seal must be installed to prevent air from being pulled into the condensate drain. The drain line should have a downward slope, with an open vent 4 inches above the trap to prevent airlocks. Ensure the unit is elevated properly for correct drainage function.

Grow Light Central expert advice for indoor growing equipment

Who should use this high efficiency dehumidifier?

Commercial growers managing large-scale hydroponic or greenhouse environments
Controlled environment agriculture facilities needing precise humidity control and filtration
Operators optimizing power efficiency with 480V low-amp draw systems
Facilities seeking Title 24 compliant equipment engineered in the USA with long-term reliability

Best applications

Large indoor grow operations requiring 730 pints/day moisture removal for stable VPD
Greenhouses and vertical farms benefiting from energy recycling via M-CoRR™ Technology
Clean rooms and labs needing MERV 13 air purification and consistent humidity balance
Industrial or tech environments like data centers and storage spaces demanding 24/7 efficiency

Why Shop with Grow Light Central?

“There’s a crapload of equipment providers out there. What makes Grow Light Central so special?”

Grow Light Central is a grow equipment solution provider connecting you to 100+ brands and 60+ suppliers trusted and used in the best grow facilities across the country.

Anthony, the owner and operator, personally ensures every order is handled right. No passing you off, no runaround, just the expert service and advice you deserve.

FAQs

What is the ideal humidity level for bud growth, and how can a humidifier help?

Seedlings thrive at 60-70% RH, vegging plants prefer 40-50% RH, and flowering needs 30-40% RH. A dehumidifier helps dial in these levels, preventing mold, mildew, and bud rot while keeping your plants healthy and maximizing yield.

What size dehumidifier do I need for my grow setup?

It depends on your grow tent or room size and how much moisture you need to pull. A 30-pint unit is great for small setups, while 50+ pint models work better for larger spaces. If you're running a big operation, go for a high-capacity unit with a built-in humidistat for full control.