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When you build the most efficient dehumidifier in the world, there’s only one thing to do next. Build one that’s more efficient AND able to eliminate performance dips caused by dirty filters and ductwork.

And that’s exactly what the engineers at Quest have done. With the introduction of the Quest 335, they’ve built a unit that pulls 335 pints of water each day and uses only 9.3 KWh to do it.

Don’t worry, we’ll get into the details but what that efficiency rating equates to is more than $85,000 saved in operating costs over the course of five years when comparing four of our machines to five of our competitor’s similarly sized dehumidifiers.

“As the need to increasingly cut energy costs continues to rise, we knew we had to push our technology further for cultivators, facility managers and engineers,” said Walt Waetjen, a Quest product manager working on the 335. “This unit does that but also has some pretty cool features not seen before in commercial dehumidification.”

quest 335 most efficient

Let’s break down how exactly the Quest team developed such a machine, what it means to you and why this is the real deal vs. marketing nonsense you couldn’t care less about.

Multi-coil magic = Unmatched efficiency

At its core, the Quest 335 uses a multi-coil design similar to the one used in the Quest 506. Fun fact: Until now, the 506 was the most energy efficient in the world.

Here’s how that multi-coil design works:

The end result is 335 pints of water pulled from the air every 24 hours at 80F and 60% relative humidity at 9.3 KWh.

To pile on the efficiency train, the 335 also has a variable speed fan (more on that, shortly) that helps the machine stay close to optimum efficiency even when the filter clogs or other static pressure is added.

“The wild thing is that with the multi-coil design, efficiency doesn’t fall dramatically as temperature and relative humidity fluctuate,” Waetjen said. “Instead, it’s a constant curve. That means at 75F and 50% RH, it still delivers results at 8.5 KWh. Most dehumidifiers in the market can’t even do that at 80F/60% RH.”

To dive deeper into the multi-coil design, check out this video with its inventor, Quest refrigeration engineer Scott Sloan.

A fan favorite: Preventing performance issues

The 335’s fan with variable speed is the “performance half” of the dynamic duo.

Coupled with a customized pressure switch, the 335’s variable speed fan automatically compensates for increased static pressure inside the dehumidifier. Why does that matter? Because, as static pressure increases, air flow through the unit decreases, resulting in decreased performance.

The primary culprits known for driving static pressure upward are dirty filters and ductwork, often added when the HVAC team wants to put the dehumidifier outside a room.

“The variable speed fan receives constant messages from the pressure switch, which is monitoring for a change in CFM. The fan slowly increases power in 1% increments to compensate for those changes until it reaches 1,000 CFM. This leads to even more consistent RH levels and no fallout in performance,” said Jerome Verhoeven, the electrical engineer responsible for the concept.

The fan/switch uses a proprietary algorithm to regularly monitor air flow and pressure. If the fan reaches 100% capacity, it will trigger a filter light so you know it’s time to put in a replacement. Knowing when to replace that filter is incredibly important, too. It’s the key piece of the system responsible for capturing particulates such as pollen, dirt and powdery mildew.

Read “A New Approach to Dehumidifier Tech That Eliminates Performance Drops” to get into the details of how the fan and switch work.

The result: More money. Fewer problems.

When you combine the dollars associated with energy consumption, reduced air conditioning usage, and the consistent environment the filter compensation feature provides, the 335 is one of the most cost-effective units on the market.

But, don’t take our word for it. The math speaks for itself

Let’s start with the scenario:

quest 335 most efficient

The result: Total cost of ownership is $81,499.50 for Quest vs. $110,625.92 for the competitor.

“Those additional costs are due to several things, including a less efficient machine at 70F/50 RH, the need for an extra dehumidifier and no filter compensation technology to maintain airflow as filters degrade,” Waetjen said. “Those are significant savings that can go toward the bottom line instead of energy and maintenance bills.”

But wait, there’s more! (Seriously, like some pretty notable features users asked for.)

Easy to service. Extra Features.

Quest didn’t stop with efficiency and performance upgrades. As it’s known for, Quest listened to its customers and incorporated several key upgrades to make installation, maintenance and monitoring easier.

On the monitoring side, the 335 has incorporated external controls from Wellington. They’re easy to read and don’t have to be wired directly to the unit. They’ve also added a dark mode, which is imperative for many cultivators.

“We always want to get our user experience right,” Verhoeven said. “It’s easy to want to do something because it’s cool from an engineering perspective, but it doesn’t mean anything if the user doesn’t care about it.”

On that front, Quest also put the cord on top of the machine so it can be plugged into the ceiling (important since most units are hung from rafters) and has a cord that can be hardwired. The latter is important so users don’t lose the UL listing if they sever the cord.

Lastly, the machine is completely serviceable – minus replacing the refrigeration unit – without removing the 335 from the ceiling. To do so, all panels can easily be removed. It also can be rinsed out with a hose.

“These may seem like minor things, but we know they’re significant to our customers,” Waetjen said. “Coupled with the fact that the 335 is the most efficient dehumidifier on the market, we’re confident it will soon be a go-to machine for cannabis cultivators and other industries as well.”