# The Best Grow Room Dehumidifiers, Sized by Plants and Water

> Nearly every gallon you pour into a pot ends up in the air. A grow room dehumidifier is how you take it back out.

Canonical: https://www.enthusiastreview.com/best/best-grow-room-dehumidifier/
Last updated: 2026-11-05
Published: 2026-11-05
Category: Specialty & Storage
Publisher: Enthusiast Review

A **grow room dehumidifier** has a harder job than a basement unit. Plants return most of the water you give them to the air, so a spare bedroom full of healthy plants can add gallons of moisture a day, right as flowering calls for drier air. This guide is for growers who've moved past a single tent to a whole room, whether that's houseplants, vegetables, hydroponic greens or cannabis where it's legal. Three things matter most: enough capacity for the water you put in, a design that keeps pulling at the 40–50% humidity late growth calls for, and hands-off drainage. Our top pick, the **AlorAir Storm Elite**, nails all three for a typical mid-size room.

For a smaller room, the **AlorAir Sentinel HDi65S** adds Wi-Fi alerts at lower capacity, and the **Waykar 158-Pint Dual Duct** connects by ducting so its heat stays outside the room. Cultivation laws vary by state and country; this page covers environmental control only, and its humidity figures are general horticulture guidance.

## Our top picks

- **Best overall:** Storm Elite — [check price on Amazon](https://www.amazon.com/dp/B09X451F5N?tag=sktiger-20&linkCode=ll1)
- **Best for small grow rooms:** Sentinel HDi65S — [check price on Amazon](https://www.amazon.com/dp/B0B3WXNDRZ?tag=sktiger-20&linkCode=ll1)
- **Best ducted pick:** Waykar 158-Pint Dual Duct — [check price on Amazon](https://www.amazon.com/dp/B0FQJM5NRR?tag=sktiger-20&linkCode=ll1)
- **Best budget high-capacity pick:** Kesnos 155-Pint — [check price on Amazon](https://www.amazon.com/dp/B0H5B4G5K4?tag=sktiger-20&linkCode=ll1)
- **Best for a closet grow or drying space:** HYDRONE 7 — [check price on Amazon](https://www.amazon.com/dp/B0G7MB9LHJ?tag=sktiger-20&linkCode=ll1)

The **AlorAir Storm Elite** is our top grow room dehumidifier because its LGR design keeps removing water at flowering humidity levels, it pumps its own drainage and it has the headroom for a room full of plants.

## 1. AlorAir Storm Elite LGR Dehumidifier — Best overall

[Check price on Amazon](https://www.amazon.com/dp/B09X451F5N?tag=sktiger-20&linkCode=ll1)

**Pros**

- LGR design keeps pulling water at 40–50% RH
- 125 pints a day at AHAM conditions
- Built-in pump sends water to a drain or sink
- Filtered intake helps in dusty rooms

**Cons**

- Takes floor space rather than hanging overhead
- More capacity than a small room needs
- Not tied into grow-tent controllers

**Why we picked it:** Humidity is easy to control early and hard in late flower, when plants are biggest and the target is lowest. The Storm Elite's low-grain design keeps extracting at those drier levels, and 125 AHAM pints give a crowded room real headroom.

**Performance:** AlorAir rates it at 125 pints a day under AHAM conditions (80°F, 60% RH) and 270 at saturation, with coverage up to about 3,000 square feet. The pump moves water to a sink or floor drain, so it runs unattended through the lights-off spike, and auto-defrost handles cooler nights. Pair it with a hygrometer at canopy height; our [best LGR dehumidifier](https://www.enthusiastreview.com/best/best-lgr-dehumidifier/) guide compares the class.

| Spec | Value |
| --- | --- |
| Capacity | 125 pints/day (AHAM); 270 at saturation |
| Type | LGR compressor |
| Drainage | Built-in pump |
| Coverage | Up to ~3,000 sq ft |
| Low-temp operation | Auto-defrost |
| Best for | Mid-size to large grow rooms |

## 2. AlorAir Sentinel HDi65S Dehumidifier — Best for small grow rooms

[Check price on Amazon](https://www.amazon.com/dp/B0B3WXNDRZ?tag=sktiger-20&linkCode=ll1)

**Pros**

- Wi-Fi app with remote humidity alerts
- Built-in pump with 19.6-ft lift
- Compact, low-profile cabinet
- Auto-defrost to about 36°F

**Cons**

- 55 AHAM pints can fall behind a crowded room
- Wi-Fi needs a decent signal in the grow space

**Why we picked it:** A spare bedroom or basement corner with a handful of plants doesn't need a restoration machine. The HDi65S is sized for that load, and its app alerts warn you when humidity climbs while you're away.

**Performance:** AlorAir rates it at 55 pints a day AHAM and 120 at saturation, for up to about 1,300 square feet. The pump lifts water 19.6 feet to a sink or window, and auto-defrost helps when a basement room cools after lights-off. It's also our multi-tent pick on the [grow tent](https://www.enthusiastreview.com/best/best-dehumidifier-for-grow-tent/) page.

| Spec | Value |
| --- | --- |
| Capacity | 55 pints/day (AHAM); 120 at saturation |
| Coverage | Up to ~1,300 sq ft (AlorAir) |
| Drainage | Built-in pump, 19.6 ft lift |
| Smart control | Wi-Fi app with alerts |
| Best for | Spare-room and closet grows |

## 3. Waykar 158-Pint Dual Duct Commercial Dehumidifier — Best ducted pick

[Check price on Amazon](https://www.amazon.com/dp/B0FQJM5NRR?tag=sktiger-20&linkCode=ll1)

**Pros**

- Intake and exhaust ducting
- Can sit outside the grow room
- Wired remote reaches about 33 feet
- Auto-defrost

**Cons**

- Capacity is rated at hot, humid test conditions
- Large and heavy

**Why we picked it:** Every dehumidifier adds heat, and in a sealed grow room that heat lands on your air conditioner. Ducting lets you park the Waykar in a hallway or utility room, pull humid air from the grow space and return it dry.

**Performance:** Waykar rates it at 158 pints a day for up to about 6,500 square feet, but at saturated test conditions rather than AHAM, so expect noticeably less in a grow room. Dual collars handle intake and exhaust, and a wired remote adjusts it from inside. Our [best Waykar dehumidifier](https://www.enthusiastreview.com/best/best-waykar-dehumidifier/) guide explains the brand's ratings.

| Spec | Value |
| --- | --- |
| Capacity | 158 pints/day (manufacturer, saturated conditions) |
| Coverage | Up to ~6,500 sq ft (brand rating) |
| Ducting | Intake and exhaust |
| Controls | Wired remote, ~33 ft |
| Best for | Sealed rooms, out-of-room installs |

## 4. Kesnos 155-Pint Commercial Dehumidifier with Pump — Best budget high-capacity pick

[Check price on Amazon](https://www.amazon.com/dp/B0H5B4G5K4?tag=sktiger-20&linkCode=ll1)

**Pros**

- High rated capacity for the money
- Built-in pump lifts water up to 16.4 ft
- Gravity hose included as a second option
- Auto-restart and auto-defrost

**Cons**

- 155-pint rating is at 95°F and 90% RH
- Not an LGR, so output fades at flowering humidity

**Why we picked it:** For a large veg room or a hydroponic setup with open reservoirs, where humidity runs high and the load is big, the Kesnos removes a lot of water for the price and pumps its own drainage up and out of the room.

**Performance:** Kesnos rates it at 155 pints a day at 95°F and 90% humidity, far wetter than a well-run grow room, so plan on meaningfully less; treat the 7,500 sq ft coverage claim as generous too. The built-in pump comes with a 16.4-foot hose and lifts water up to 16.4 feet, and a separate gravity hose is included. See our [best Kesnos dehumidifier](https://www.enthusiastreview.com/best/best-kesnos-dehumidifier/) guide.

| Spec | Value |
| --- | --- |
| Capacity | 155 pints/day (95°F/90% RH) |
| Coverage | Up to 7,500 sq ft (brand rating) |
| Drainage | Built-in pump (16.4-ft lift) or gravity hose |
| Controls | 10–90% RH humidistat, 24-hour timer |
| Restart | Auto-restart after outages |
| Best for | Large veg rooms, hydroponic setups |

## 5. AC Infinity HYDRONE 7 Plant Dehumidifier — Best for a closet grow or drying space

[Check price on Amazon](https://www.amazon.com/dp/B0G7MB9LHJ?tag=sktiger-20&linkCode=ll1)

**Pros**

- Built for plant spaces
- Onboard humidity and VPD controller
- Sized for large tents and small rooms

**Cons**

- About 610 watts adds real heat
- Lower capacity than full-size room units

**Why we picked it:** Some grow rooms are really oversized closets, and some growers want a second unit for a separate drying space. The HYDRONE 7 is designed around plants, with controls that speak in humidity and VPD targets.

**Performance:** AC Infinity lists a draw rate of about 8 liters (roughly 17 pints) a day at about 610 watts, for up to 8x8 or 10x10 tents; that figure isn't comparable to AHAM ratings. In a closed room, exhaust its heat or duct dry air in from outside. More in our [AC Infinity dehumidifier](https://www.enthusiastreview.com/best/best-ac-infinity-dehumidifier/) guide.

| Spec | Value |
| --- | --- |
| Draw rate | About 8 L (17 pints)/day (AC Infinity) |
| Coverage | Up to 8x8–10x10 tents |
| Power | 120V, about 610 W |
| Control | Built-in humidity/VPD controller |
| Best for | Closet grows, small drying rooms |

## Grow room moisture, by the numbers

- **90%+** — Share of the water plants take up that they release back into the air through transpiration
- **8 pints** — Moisture in every gallon of water you feed, the basis of grow room sizing
- **40–50%** — Common flowering humidity target, lower than most home units are built for

Put together, the math is simple: water in roughly equals moisture out. Pour 6 gallons a day and the room must shed close to 48 pints of vapor, plus evaporation from soil, trays and reservoirs.

## How we pick grow room dehumidifiers

We compared rated capacity and the conditions behind each rating (AHAM, saturation or a brand's own test), drainage, ducting, low-humidity performance, controls and power draw, then read manuals, extension-service guidance on indoor growing humidity and owner reviews from growers. We don't lab-test units ourselves; every capacity figure is the maker's rating.

## Grow room dehumidifiers compared

| Model | Capacity rating | Drainage | Key feature | Best for |
| --- | --- | --- | --- | --- |
| AlorAir Storm Elite | 125 pints AHAM | Built-in pump | LGR for low flowering RH | Mid-size to large rooms |
| AlorAir Sentinel HDi65S | 55 pints AHAM | Pump, 19.6 ft lift | Wi-Fi alerts | Small rooms, a few plants |
| Waykar 158-Pint Dual Duct | 158 pints (saturated) | Continuous drain | Intake and exhaust ducting | Sealed rooms |
| Kesnos 155-Pint | 155 pints (95°F/90% RH) | Pump, 16.4-ft lift | ENERGY STAR | Big veg and hydro rooms |
| AC Infinity HYDRONE 7 | ~17 pints real-world | Plan a drain line | VPD controller | Closets, drying spaces |

*Ratings use different test conditions; AHAM (80°F, 60% RH) is the most realistic for a grow room. Saturation and brand figures overstate everyday output.*

## How big a dehumidifier for a grow room?

Square footage barely matters here. What sizes a grow room dehumidifier is how much water goes in. Use this simple grow room dehumidifier calculator:

1. **Add up daily watering** in gallons, including nutrient solution. Subtract any runoff you collect and remove from the room.
2. **Multiply by 8** to get pints of moisture per day.
3. **Add 10–25%** for open reservoirs, wet floors and evaporation from trays, more for hydroponic rooms.
4. **Compare against the AHAM rating**, and add more headroom if your unit is rated at saturation or you're targeting the low 40s.

| Room | Daily watering | Moisture load | Suggested class |
| --- | --- | --- | --- |
| Closet or small corner | 1–2 gallons | 8–16 pints | HYDRONE 7 or a household 35–50 pint unit |
| Spare bedroom, a few plants | 4–6 gallons | 32–48 pints | Sentinel HDi65S (55 AHAM) |
| Mid-size room, full canopy | 8–12 gallons | 64–96 pints | Storm Elite (125 AHAM) |
| Large room or hydroponic setup | 15+ gallons | 120+ pints | Storm Elite plus a second unit, or a ducted commercial unit |

*Rough guidance. Lights-off periods often spike humidity as the room cools, so size for the worst hour, not the average.*

For everyday rooms, our [dehumidifier size guide](https://www.enthusiastreview.com/guides/dehumidifier-size-guide/) uses square footage and dampness; for a grow room, the watering math above is more reliable.

## How to choose a grow room dehumidifier

- **Size by water, then add headroom:** Start from the calculator above. A unit running flat out all day can't catch up after lights-off.
- **Choose LGR if you flower:** Standard compressor units lose much of their output below about 50% humidity. Low-grain refrigerant units are designed to keep working there, which is where late flower lives.
- **Plan for the heat:** A dehumidifier puts out its own power draw as heat, plus the heat released when vapor turns to water. In a sealed room, your AC has to remove that too, or you can duct the unit outside the room.
  - Our guide to [how much electricity a dehumidifier uses](https://www.enthusiastreview.com/guides/how-much-electricity-does-a-dehumidifier-use/) helps estimate the load
- **Insist on a pump or a drain:** A grow room dehumidifier may pull several gallons a day. Bucket models will stop when full, often in the middle of the night.
- **Use a separate hygrometer:** Built-in sensors read humidity at the machine. A [good hygrometer](https://www.enthusiastreview.com/best/best-hygrometer/) at canopy height tells you what the plants actually experience.
- **Count your circuits:** Lights, fans, pumps and AC already load the room. Keep each 15-amp circuit under about 12 amps of continuous draw and give big units their own outlet.
- **Keep the filter clean:** Perlite dust and plant debris clog intakes fast and cut capacity; check the filter every week or two.

## What humidity should a grow room be?

| Stage | Typical humidity | Typical temperature | Notes |
| --- | --- | --- | --- |
| Seedlings and clones | 65–75% | 70–80°F | Humidity domes help early on |
| Vegetative growth | 50–70% | 70–85°F | Lower the target as plants fill the room |
| Flowering | 40–50% | 65–80°F | Dense flowers are prone to gray mold in damp air |
| Late flower | 30–40% (many growers) | 65–75°F | The hardest target for standard dehumidifiers |
| Drying (where legal) | 55–62% | 60–70°F | A separate, slower environment |

*General horticulture guidance; adjust for your plants, your setup and your local laws. Many growers fine-tune with vapor pressure deficit (VPD) charts.*

> **Watch the lights-off spike:** When lights switch off, the room cools and relative humidity jumps even though no extra water was added. Set the dehumidifier to run through that window and check your hygrometer's history for overnight peaks.

## Using a dehumidifier for drying cannabis and herbs

Drying is a different job from growing. Where it's legal, most guidance calls for a dark, cool space around 60–70°F at roughly **55–62% humidity** for a week or two, so material dries evenly. A big grow room unit is usually too much; a small unit with a precise humidistat, or the HYDRONE 7, works better.

- Use a separate room, closet or tent, not the active grow room.
- Keep fans pointed at walls, not directly at hanging material.
- Check humidity twice a day early on, when the most moisture is released.

Our [drying room dehumidifier](https://www.enthusiastreview.com/best/best-dehumidifier-for-drying-room/) guide covers setup, curing ranges and the right small units in detail.

## Placement, ducting and drainage

### Inside or outside the room?

Inside is simplest: set the unit low, a foot or more from walls and plants, where room fans move air past it. In sealed rooms with AC, outside is better, because the unit's heat stays out; duct humid air to it and dry air back, as with the Waykar or a [ducted dehumidifier](https://www.enthusiastreview.com/best/best-ducted-dehumidifier/).

### Hydroponic rooms

A hydroponic dehumidifier also has to handle evaporation from reservoirs and channels. Lidded reservoirs and covered trays cut that load noticeably.

### Drainage

Run a pump line or hose to a floor drain, sink or container and check it each visit; a kinked hose on a high-capacity unit can flood a floor overnight.

## Which one should you buy?

- **A mid-size room with a full canopy in flower:** the AlorAir Storm Elite.
- **A spare bedroom or basement corner with a few plants:** the AlorAir Sentinel HDi65S, with Wi-Fi alerts.
- **A sealed room with AC where heat is the problem:** the Waykar 158-Pint Dual Duct, installed outside the room.
- **A large veg room or hydroponic setup on a budget:** the Kesnos 155-Pint, remembering its rating is optimistic.
- **A closet grow or a separate drying space:** the AC Infinity HYDRONE 7.
- **Still growing in tents?** Start with our [grow tent dehumidifier](https://www.enthusiastreview.com/best/best-dehumidifier-for-grow-tent/) picks, and step up to a room unit when you outgrow them.

## The bottom line

Size a grow room dehumidifier by the water you pour in, not the square footage, and favor a design that keeps working at flowering humidity. For most rooms, buy the **AlorAir Storm Elite**. Go smaller with the **Sentinel HDi65S**, ducted with the **Waykar 158-Pint Dual Duct**, cheaper with the **Kesnos 155-Pint** and compact with the **AC Infinity HYDRONE 7**, and confirm the room with a hygrometer at canopy height.

## Frequently asked questions

### What size dehumidifier do I need for a grow room?

Multiply your daily watering in gallons by 8 to get pints of moisture, add 10–25% for evaporation, then choose a unit whose AHAM rating covers that with room to spare. A room watered with 6 gallons a day needs roughly 50–60 pints of real capacity.

### What is the best dehumidifier for a cannabis grow room?

For most mid-size rooms, the AlorAir Storm Elite. Its LGR design keeps removing water at the 40–50% humidity flowering calls for, and its built-in pump handles drainage. Smaller rooms suit the AlorAir Sentinel HDi65S.

### Is a commercial dehumidifier worth it for a grow room?

Usually, once you're past one or two tents. Household units are built for basements and fade at flowering targets; commercial and LGR units handle heavy, continuous loads and drain automatically.

### Can I use a regular dehumidifier in a grow room?

For a small room or veg-only space, a household 50-pint unit with a pump or drain hose can work. In a full room in flower, it will often run nonstop without reaching 40–50%, so an LGR or commercial unit is the better buy.

### Should I use a dehumidifier when drying cannabis?

Where it's legal, a small dehumidifier helps hold a drying space at about 55–62% humidity and 60–70°F. The goal is slow, even drying, so set a target rather than running it at full power. See our drying room guide for setup details.

### Where should a dehumidifier go in a grow room?

Low in the room, a foot or more from walls and plants, where fans move air past it. In sealed rooms with AC, a ducted unit outside the room keeps its heat out of the grow space.

## Related guides

- [The Best Dehumidifiers for Grow Tents](https://www.enthusiastreview.com/best/best-dehumidifier-for-grow-tent/)
- [The Best Dehumidifiers for Drying Rooms, Herbs and Cannabis](https://www.enthusiastreview.com/best/best-dehumidifier-for-drying-room/)
- [The Best AC Infinity Dehumidifiers for Grow Tents](https://www.enthusiastreview.com/best/best-ac-infinity-dehumidifier/)
- [The Best LGR Dehumidifiers for Flooded Basements and Water Damage](https://www.enthusiastreview.com/best/best-lgr-dehumidifier/)
- [The Best Ducted Dehumidifiers for Your HVAC System](https://www.enthusiastreview.com/best/best-ducted-dehumidifier/)
- [The Best Commercial Dehumidifiers for Restoration and Job Sites](https://www.enthusiastreview.com/best/best-commercial-dehumidifier/)

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*Enthusiast Review researches products against DOE ratings, ENERGY STAR data, manuals, CPSC recalls and owner reviews; it does not run a test lab. Amazon links are affiliate links (tag sktiger-20).*