Quest PowerDry 4000 Pro 176 Pint Dehumidifier is no longer available

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Quest PowerDry 4000 Pro 176 Pint Dehumidifier is no longer available

SKU #: HGC700824

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  • Dehumidifier Type
    Free Standing
  • Exact Moisture Removal Capacity (Pints/Day)
    176 Pints/Day
  • Amps
  • Efficiency Rating
    6.2 Pints/kWh
  • Warranty
    5 Year

The Quest PowerDry 4000 is the solution for growers wanting the flexibility and convenience of a large capacity portable dehumidifier. With over 22 gallons (176 pints) of capacity, the Quest PowerDry 4000 is ready for the toughest challenge.

Whether you are a grower looking for a dehumidifier with serious capacity for the most critical peaks of the grow cycle, a large supplemental dryer, or the flexibility of a product that can be moved to various rooms when needed, the Quest PowerDry 4000 is the product for you.

The PowerDry 4000 Pro also comes equipped with a solid-state control panel that is easy to read and operate. Another unique and innovative feature of the PowerDry 4000 Pro is the on board humidistat, which is located on the control panel. This feature gives the grower the ability to set the unit at a particular humidity level (between 20-70%RH) and the PowerDry will maintain that level throughout the growing process. When a specific humidity level is critical the PowerDry 4000 Pro is the perfect choice.

The Quest PowerDry 4000 is the flagship dehumidifiers in the Quest line of portable products, is constructed of the highest quality components, and is protected by a heavy duty Stainless Steel shell. Compared to other products, made of cheap plastic, the Quest PowerDry 4000 is simply the best product available, is built in the USA, and is designed to last for many years to come. No other portable dehumidifier comes close to the performance or quality of the Quest PowerDry 4000. Included with every Quest PowerDry 4000 is a high capacity filter. High capacity filtration is designed to capture mold, spores, pollen, and dust effectively cleansing the room of dangerous particles. When it comes to keeping your plants safe from mold, mildew, bacteria, and disease, accept no substitute.


  • Blower: 380 CFM
  • Power: 1170 Watts
  • Supply Voltage: 115 volt - 1 phase - 60 Hz
  • Amps: 10
  • Energy Factor: 2.93 L/kWh
  • Operating Range: 33 degrees F - 110 degrees F
  • Water Removal: 176 Pints/Day @ 80 degrees F, 60%RH
  • Efficiency: 6.2 Pints/kWh
  • Air Filter: 2" Pleated Media MERV-11
  • Power Cord: 25 - 115 volt grounded plug
  • Merv 11 filtration
  • Warranty: 1 year parts and labor - 5 year compressor and refrigerant system

Warranties on Quest Dehumidifiers are served by the manufacturer.

Tech Specs


Weight (lb.)135
Length (in.)20
Width (in.)23
Height (in.)40
Warranty5 Year
Prop 65No
UL ListedYes
Exact Moisture Removal Capacity (Pints/Day)176 Pints/Day
Efficiency Rating6.2 Pints/kWh
Dehumidifier FeaturesIncludes Drain Hose, Built-In Pump, Auto Restart
Dehumidifier TypeFree Standing
Drain Hose Length30 ft.
Lead TimeShips in 6-7 Business Days
Air FilterMERV-11 - 2” Pleated Media
Power Cord(s) Included25 ft. - 120 Volt Grounded Plug
Power Cord Length25 ft.
Exact Watts1170 Watts
Voltage120 Volts

Quest PowerDry 4000 Pro 176 Pint Dehumidifier Videos

Product Q&A

Quest PowerDry 4000 Pro 176 Pint Dehumidifier Questions & Answers

How do I size a dehumidifier for a grow room?
Plants transpire about 97% of the water they receive, so the amount of water your plants consume is approximately the amount that needs to be removed each day. For example, 30 plants each receiving ½ gallon per day is an average of 15 gallons water per day. Every gallon of water is 8 pints. This example works out to 120 pints per day.

Isn’t my air conditioner a dehumidifier?
Yes, but there are issues with this solution.
1. Air conditioners remove water only when they are running. In most cases when the grow lights are off, the air conditioner is off as well. Lights-off time is when humidity is most problematic.

2. Using an air conditioner to dry a room will overcool the room, potentially causing plant stress. This will also use a significantly greater amount of energy than a Quest commercial dehumidifier.

3. The more energy efficient the air conditioner, the less moisture it actually removes. An efficient air conditioner is a terrible dehumidifier.

4. The re-heat method. Some air conditioners offer an optional heating coil as a dehumidification option. Essentially, by adding artificial heat to the room, the air conditioner is forced to operate when the lights are off and thus the air conditioner removes water. While this method works, and can be used in a pinch, it’s a poor long term solution and will use 4-8x the energy as a Quest dehumidifier. 4-8x the energy use is roughly equal to $5,000-$25,000 per year in unnecessary energy consumption.

What if I live in Arizona, New Mexico or a dry state, do I need a dehumidifier?
While it may be dry outdoors, growing in a sealed environment changes things a good bit. Growers using sealed rooms, even in the driest of outdoor climates, almost always require dehumidifiers. The higher quality of the grow room design and construction, the more critical a dehumidifier will be.

What is the ideal humidity?
Because every plant is different, it is hard to pick just one number. However, most research indicates that 45-55% RH is the safe zone where plants are healthy, spore germination is unlikely, and pests find the environment unappealing.

How much money does a Quest dehumidifier save me in electricity?
Quest is the leader in energy efficiency and one of our models is the most energy efficient dehumidifier ever built. Depending on the model, Quest dehumidifiers can save commercial growers $100-$200 a month in electricity per unit. That’s $1,200-$2,500 per dehumidifier per year.

Can the water be reused?
Yes, Quest dehumidifiers produce neutral pH, very low TDS water. This water is safe for all plants, even consumable ones.