Quest Dual 150 Overhead Dehumidifier

The Quest Dual 150 Overhead Dehumidifier is a 150-pint-per-day unit engineered for grow rooms where floor space matters. It mounts overhead to stay out of the way, runs plug and play on standard power with no installation required, and ships with a replaceable MERV-8 filter. Optional condensate pump and ducting kits extend flexibility for spaces with challenging layouts. Made in the USA.

Quest Dual 150 Overhead Dehumidifier Specifications

The specifications below are drawn from the canonical product data and the manufacturer’s listed attributes. The Quest Dual 150 carries a single confirmed weight attribute; all other fields are sourced from the product description text.

Specification	Value
Brand	Quest
Model	Dual 150 Overhead
Capacity	150 pints per day
Energy Efficiency	>4.9 pints per kWh
Weight	95.09 lb (43.1 kg)
Mounting Style	Overhead (ground-level placement also supported)
Installation	Plug and play — no installation required
Filter	MERV-8, replaceable
Optional Accessories	Condensate pump, ducting kits (sold separately)
Country of Origin	USA

Why Choose the Quest Dual 150 Overhead Dehumidifier

The Quest Dual 150 is designed for cultivators who need reliable humidity control without sacrificing floor space. Here is what makes it a practical choice for indoor growing environments:

• Overhead mounting keeps floor space clear. The Dual 150 was built to hang above the canopy, out of the way of plant traffic, irrigation lines, and other ground-level equipment. It can also sit at ground level if overhead mounting is not an option.
• Plug and play operation — no installation required. Unlike ducted or hardwired dehumidifiers, the Dual 150 runs on a standard outlet. There is no contractor call and no downtime waiting for an install window.
• Better value efficiency than the Dual 155. Quest rates the Dual 150 at over 4.9 pints per kWh, which is a lower efficiency figure than the Dual 155 (rated at 7.3 pints per kWh). For growers who want a capable unit at a lower price point and can accept the efficiency trade-off, the Dual 150 delivers solid performance.
• Flexible condensate handling with optional accessories. An optional condensate pump and ducting kits let you route drain water to a remote location, which is important in rooms where floor drains are not ideally placed or where the unit is mounted overhead.
• MERV-8 filter included and user-replaceable. The onboard MERV-8 filter traps airborne particles before they reach the refrigeration coils. Replacement filters are a standard size and easy to swap without tools or service calls.
• Made in the USA. Quest manufactures this unit domestically, which typically means shorter lead times for warranty service and parts compared to overseas-sourced alternatives.

Best Uses for the Quest Dual 150 Overhead Dehumidifier

The Dual 150 fits a range of indoor cultivation and controlled-environment applications. Below are the scenarios where it tends to perform most reliably:

• Mid-size grow rooms with overhead clearance. If you have a room with 9–14 foot ceilings and need to keep the floor clear for benching, carts, or canopy access, overhead mounting puts the dehumidifier where it does not interfere with daily operations.
• Commercial cultivation facilities transitioning from consumer-grade dehumidifiers. The Dual 150 is in a class suited to growers moving past small portable units. Its 150-pint-per-day capacity handles rooms where a household dehumidifier would cycle constantly and still fall short.
• Spaces with restrictive drain or ventilation layouts. The optional condensate pump and ducting kits are designed specifically for rooms where a gravity drain or direct duct connection is not straightforward. If your mechanical room is on the other side of a wall, the pump kit solves that problem without major renovation.
• Facilities looking for plug-and-play deployment. Growers who need to add dehumidification capacity quickly — during a buildout, after a system failure, or when scaling up — benefit from the Dual 150’s no-installation requirement. Plug it in, set the target humidity, and it runs.
• Paired with a condensate pump for overhead drain routing. Growers mounting the unit above the canopy frequently combine it with a condensate pump to move water away from the unit without relying on gravity drain lines.

Quest Dual 150 vs Quest Dual 155

Quest produces several overhead dehumidifiers in the Dual series. The two most directly comparable models are the Dual 150 and the Dual 155. Understanding the trade-offs helps you choose the right unit for your room size and operating costs.

Energy efficiency: The Dual 155 is rated at 7.3 pints per kWh, compared to the Dual 150 at over 4.9 pints per kWh. The Dual 155 removes significantly more moisture per unit of electricity consumed. In a facility running dehumidifiers continuously across multiple rooms, this difference adds up in operating costs. The Dual 150 is positioned as a lower-cost entry into the overhead dehumidifier category, trading some efficiency for a lower purchase price.

Capacity: Both models are overhead units, but if your room’s moisture load requires the higher-efficiency processing of the Dual 155, the Dual 150 may need to run more hours or may not fully keep pace during peak transpiration periods. For rooms that fall within the Dual 150’s rated capacity, the efficiency gap matters primarily in operating cost rather than dehumidification ability.

Who should choose the Dual 150: Growers with moderate moisture loads who want overhead mounting and plug-and-play setup without the higher purchase price of the Dual 155. If you are running a single room or are cost-sensitive on upfront equipment, the Dual 150 is a practical choice. If you are building a multi-room commercial facility focused on minimizing long-term energy spend, compare the operating cost difference before buying.

Both units support optional condensate pump and ducting kits, and both ship with a MERV-8 filter. The core operational workflow is the same between the two models.

Compatibility & Operating Range

The Quest Dual 150 is designed for indoor cultivation environments. Its plug-and-play design means it works with standard electrical infrastructure without requiring dedicated circuits or hardwiring in most installations. The following notes apply:

• Electrical: Plug-and-play operation on standard power. Verify your outlet and circuit capacity match the unit’s draw before plugging in — consult the Quest spec sheet at questclimate.com for exact amperage requirements.
• Mounting hardware: Overhead mounting requires appropriate ceiling or rafter support rated for the unit’s weight (95 lb). Quest and third-party suppliers offer hanging kits compatible with the Dual 150 form factor.
• Condensate management: The unit drains via gravity by default. The optional condensate pump accessory is required for overhead installations where gravity drainage to a floor drain is not feasible.
• Ducting: Optional ducting kits allow the Dual 150 to draw from or exhaust to adjacent spaces. This is useful in multi-room facilities where return air routing is part of the HVAC design.
• Temperature range: Quest overhead dehumidifiers are rated for typical indoor grow room temperatures. Manufacturer-published operating temperature and humidity range data is available on the Quest climate product pages.
• Filter compatibility: The included MERV-8 filter is a replaceable standard. Replacement filters must match the Dual 150’s filter dimensions — confirm the part number with Quest before ordering replacements from third-party suppliers.

For rooms that also need active air circulation, pairing the Dual 150 with a pedestal circulation fan helps distribute dehumidified air evenly across the canopy rather than letting it stratify near the unit.

Usage Guidelines

Getting consistent performance from the Quest Dual 150 comes down to placement, target setpoint, and routine maintenance. These guidelines are based on the product description and general best practices for overhead dehumidifiers in cultivation environments.

Setting the target humidity: Set the unit’s humidistat to your target relative humidity (RH) for the current growth stage. Vegetative stages typically target 50–70% RH, while late flower stages often call for 40–50% RH to reduce mold pressure. Adjust the setpoint as plants transition between stages rather than leaving it fixed for the entire cycle.

Overhead placement: When mounted overhead, position the unit so its discharge airflow moves across the canopy rather than straight down into a single zone. The goal is to draw humid air from the room, dehumidify it, and return drier air in a pattern that reduces humidity pockets. Avoid placing the unit directly above dense canopy foliage where air circulation is restricted.

Ground-level placement: If ceiling mounting is not practical, the Dual 150 can sit at ground level. In this configuration, direct its discharge toward open aisle space or toward an oscillating fan to help distribute dehumidified air throughout the room. Ground-level placement may reduce effectiveness in tall canopy rooms where humidity concentrates at canopy height.

Condensate drain: Gravity drain requires a floor drain within reach of the drain line. If running the unit overhead or if no floor drain is available nearby, install the optional condensate pump to route water to a remote drain. Check the condensate line and pump reservoir periodically to ensure the drain path stays clear.

Filter maintenance: The MERV-8 filter requires periodic inspection and replacement. In rooms with higher airborne particulate (dried plant matter, perlite dust, diatomaceous earth), check the filter monthly. A clogged filter reduces airflow across the coils and reduces dehumidification capacity. Replace the filter per Quest’s recommended schedule or when the filter shows visible loading.

Monitoring: Use a separate humidity monitoring solution at canopy level to verify that the room’s RH matches your setpoint. The unit’s onboard humidistat reads conditions at the unit’s intake, which may differ from canopy-level conditions, especially in larger rooms.

How to Set Up the Quest Dual 150

The Quest Dual 150 is plug and play and does not require installation in the traditional sense. Setup involves mounting (if overhead), connecting drainage, and powering the unit. The steps below cover both overhead and ground-level deployment.

1. Choose your mounting position. Decide whether you will mount the unit overhead or place it at ground level. Overhead mounting requires ceiling, rafter, or structural support rated for at least 95 lb (the unit’s weight plus safety margin). Identify your mounting point before moving the unit into position.
2. Install overhead mounting hardware (overhead deployment only). Use a Quest-compatible hanging kit or appropriately rated mounting hardware. Attach mounting brackets or chains to the structural support. Ensure the unit will hang level — a tilted unit can affect condensate drainage to the internal drain pan.
3. Position the unit for discharge coverage. Orient the discharge louvers so dehumidified air flows across the room’s canopy zone. For ground-level placement, aim the discharge toward open aisle space or into the path of a circulation fan.
4. Connect the condensate drain line. For gravity drain, route the drain line from the unit’s drain port to a nearby floor drain. Keep the line as short as possible and avoid uphill runs. For overhead mounting or where a floor drain is not accessible, install the optional Quest condensate pump and route the pump discharge line to a suitable drain point.
5. Install or inspect the MERV-8 filter. Confirm the filter is seated correctly in the filter housing before running the unit. The filter ships installed; inspect it to ensure it was not displaced during shipping.
6. Plug in the unit. Connect the unit’s power cord to a grounded outlet that matches the unit’s voltage and amperage requirements. Do not use an extension cord for permanent operation.
7. Set the target humidity. Power on the unit and set the onboard humidistat to your desired target RH. Allow the unit to run through a full cycle before adjusting the setpoint — it takes time for the room’s RH to respond, especially on first startup in a humid room.
8. Verify condensate drain flow. After the unit has run for 30–60 minutes, check that condensate is flowing through the drain line. If water is pooling inside or under the unit, inspect the drain line for kinks or blockages.
9. Log filter install date. Note the date the filter was first installed so you can track replacement intervals based on actual run time and room conditions.

Sources & Further Reading