Merris Air Curtain Burners — WX-5 & WX-8

On-Site Wood Waste Disposal at $21 Per Ton

The Merris WX-5 and WX-8 air curtain burners eliminate land-clearing debris on the job site. No grinder. No haul trucks. One operator.

Starting at $142,500.

$21.76

Per ton all-in
operating cost

3-9

Tons per hour
(model-dependent)

75%

Less than annual
cost of grinding

Parts stocked in Smyrna, GA

Ships same or next day

Direct engineer support

Not a call center

On-site setup & training

Included with every machine

Nationwide field technicians

Insured, on-call

98% Volume Reduction

A 200-ton debris pile becomes approximately 2 to 3 tons of ash.

Land-clearing contractors working timber and brush removal average 40 to 200 green tons per acre. Pipeline corridor clearing, utility right-of-way work, and residential site prep often push higher. All of that material needs to go somewhere. Most of it has no commercial market. Most of it cannot be left on-site. The question is not whether you deal with it. The question is what it costs you to do it.

Hauling and Grinding Are the Two Expensive Options Nobody Questions

Hauling runs approximately $55.80 per ton in Georgia when you add tipping fees, trucking, and driver time. On a 200-ton clearing job, that is $11,160 out the door before the next crew can move in. Larger jobs compound fast. Pipeline corridor work at 500 tons is $27,900 in pure disposal cost.

Grinding is the other default. A mid-size horizontal grinder costs $244 to $274 per hour to operate all-in. The per-ton cost at working volume comes to approximately $85. The grinder also requires a dedicated mechanic, a service truck, and a carbide tip budget that has increased 885% since January 2025. Tips that cost $335 per MTU in early 2025 now run $3,050. That is not a wear cost fluctuation. That is a structural cost increase that changes the economics of grinding for disposal.

And neither method leaves you with anything. You pay to haul, or you pay to grind material no one is buying, and the cost shows up on every job.

SINCE 1973

We have been selling equipment to land-clearing crews, utility contractors, and site prep operations since 1973. We know what a 200-ton clearing job looks like when the debris piles up and the haul trucks start running. We know the math on grinding margins when carbide costs escalate mid-season. The Merris WX-5 and WX-8 are the answer to that math. We stock parts for both models in Smyrna, Georgia, and we come to your site to commission the machine with your crew. This is not a machine you buy online and figure out on your own.

How an Air Curtain Burner Eliminates Wood Waste

An air curtain burner is a refractory-lined firebox with a high-velocity air manifold mounted above the opening. The blower forces a horizontal curtain of air across the top of the firebox at high speed. That air curtain does two things: it contains smoke inside the box, and it drives secondary combustion at temperatures above 1,800°F. The result is near-smokeless operation and up to 98% volume reduction. A 200-ton debris pile becomes approximately 2 to 3 tons of ash.

Step 1

Load

Feed logs, limbs, stumps, and brush into the firebox with an excavator or loader. The WX-5 and WX-8 door opening is 6′3″. Most excavator buckets load directly without pre-processing.

Step 2

Ignite

Start the blower engine. Ignite the load. The air curtain establishes within minutes and drives secondary combustion at 1,800°F+. Smoke that would escape is forced back into the combustion zone.

Step 3

Burn

Add material as the load burns down. One operator manages loading and monitors the burn. The WX-5 processes 3 to 6 tons per hour. The WX-8 processes 6 to 9 tons per hour.

Step 4

Ash Out

Rake out the residue. A 200-ton debris load produces approximately 2 to 3 tons of ash, roughly 4 to 6 cubic yards. What required 8 to 11 haul trips leaves the site in a single bucket.

What Disposal Actually Costs You Per Ton

At $21.76 per ton all-in, the Merris WX-8 is the cheapest method to eliminate wood waste on-site. The gap against the alternatives is not marginal.

$21.76

Per ton — WX-8

Fuel, one operator, equipment amortization

$55.80

Per ton — Haul & Dump
Tipping fee + trucking + driver time (GA rates)

$85.00

Per ton — Horizontal Grinder
Fuel, tips, two operators, mechanic, depreciation

Method

Cost Per Ton

5,000 Tons/Year

Notes

MethodAir curtain burner (WX-8)

Cost Per Ton$21.76

5,000 Tons/Year~$108,800

NotesFuel, one operator, equipment amortization

MethodHaul and dump

Cost Per Ton$55.80

5,000 Tons/Year~$279,000

NotesTipping fee + trucking + driver time (GA rates)

MethodHorizontal grinder

Cost Per Ton$85.00

5,000 Tons/Year~$425,000

NotesFuel, tips, two operators, mechanic, depreciation

The grinder also requires overhead that the burner does not: a dedicated mechanic (approximately $75,000 per year loaded), a service truck (approximately $18,000 per year amortized), and a carbide tip budget that now runs $15,000 to $20,000 per year at 2026 pricing and climbing.

WX-5 or WX-8 — Which Fits Your Operation?

WX-5

$142,500

Burn rate 3–6 tons/hr

Burning area 13Ȳ4″ × 5Ȳ6″ × 6Ȳ0″

External size 22Ȳ7″ × 7Ȳ3″ × 7Ȳ3″

Weight 18,000 lbs

Engine 24 HP Yanmar or Kohler

Fuel tank 24 gallons

Fuel consumption ~1 gal/hr

Loading height 6Ȳ3″ door opening

Choose the WX-5 if:
You are clearing 1 to 3 acres per day, running a single crew on residential or light commercial site prep, or need a machine a standard rollback can transport to multiple sites per week.

Production Volume

WX-8

$171,500

Burn rate 6–9 tons/hr

Burning area 21Ȳ5″ × 5Ȳ6″ × 6Ȳ0″

External size 30Ȳ4″ × 7Ȳ3″ × 7Ȳ3″

Weight 24,000 lbs

Engine 47.9 HP Yanmar or Kohler

Fuel tank 33 gallons

Fuel consumption ~2–3 gal/hr

Loading height 6Ȳ3″ door opening

Choose the WX-8 if:
You are running utility corridor, pipeline right-of-way, or large commercial clearing where a single site generates 200 to 500 tons of debris. The larger firebox accepts longer logs without cutting first.

Prices as of August 2026. Subject to change. Financing available — call 770-433-2670.

Approved Materials and EPA Requirements

Air curtain burners operate under EPA 40 CFR Part 60. The approved material list is not a recommendation — it is a federal requirement. Burning prohibited materials is an EPA violation.

Approved Materials

Logs and limbs
Brush and stumps
Untreated lumber
Yard and garden debris
Natural forest residue
Agricultural waste (where state-permitted)
Root balls

Prohibited Materials

Pressure-treated lumber
Plywood, painted, or stained wood
Creosote-treated timber, railroad ties
Utility poles
Plastics of any kind
Engineered wood products
C&D debris or contaminated material

Temporary use typically requires a burn permit from the local fire marshal or state forestry department. Requirements vary by state, county, and duration. We do not obtain permits for buyers. Call 770-433-2670 — we can tell you what other contractors in your state have encountered.

What Your Operation Looks Like With a WX-8 Running

A land-clearing crew running a 200-ton site currently hauls 8 loads at $55.80 per ton — $11,160 in disposal before the next phase of the job can begin. With the WX-8 running at 6 to 9 tons per hour, that same 200 tons burns in 22 to 33 hours. One operator. Approximately $237 in fuel at current diesel prices. No haul trucks. No tipping fees.

On an annualized basis at 5,000 tons per year, the WX-8 saves approximately $316,200 against the cost of equivalent grinding. It pays for itself against hauling costs in under 12 months at 500 tons per year.

Merris vs. FireBox: How They Compare

Air Burners Inc. makes the FireBox series — the most widely known air curtain burner line in North America. Both are legitimate machines that operate on the same principle. The differences are weight, burn rate, and what it takes to move them between sites.

Spec

Merris WX-5

FireBox S-116 / S-119

SpecBurn rate

Merris WX-53–6 tons/hr

FireBox S-116 / S-1192–5 tons/hr

SpecWeight

Merris WX-518,000 lbs

FireBox S-116 / S-11927,500–30,100 lbs

SpecPrice

Merris WX-5$142,500 (published)

FireBox S-116 / S-119Not published

SpecTransport

Merris WX-5Standard flatbed, no oversize permit

FireBox S-116 / S-119Standard flatbed

Spec

Merris WX-8

FireBox S-220

SpecBurn rate

Merris WX-86–9 tons/hr

FireBox S-2205–9 tons/hr

SpecWeight

Merris WX-824,000 lbs

FireBox S-22036,650–40,250 lbs

SpecPrice

Merris WX-8$171,500 (published)

FireBox S-220Not published

SpecTransport

Merris WX-8Standard flatbed, no oversize permit

FireBox S-220Standard flatbed

The weight difference matters. The WX-5 is approximately 10,000 lbs lighter than a comparable FireBox 100 Series unit. For a contractor moving between sites regularly, lighter means lower transport cost, fewer road weight restrictions, and faster mobilization. FireBox 300 Series units require oversize permits. Neither Merris model does.

FireBox specs sourced from airburners.com, August 2026. FireBox pricing not published. Merris pricing confirmed August 2026.

Keep the Operation Running

FyreBx skid steer attachments built for what you run alongside this machine.

FyreBx

FuelBx: On-Site Diesel Refueling

The WX-5 burns approximately 1 gallon of diesel per hour. The WX-8 burns 2 to 3 gallons per hour. On a remote clearing site, a fuel truck visit breaks the burn day. The FuelBx carries 300 gallons of diesel on the front of a skid steer and delivers it through a 50-foot hose reel — no fuel truck scheduling, no machine shutdown.

Learn More →

FyreBx

LandBx: Ash Dust Control

After a burn cycle, disturbing the ash bed during raking kicks up fine particulate. On sites near residential areas or in dry conditions, that dust becomes a complaint. The LandBx mounts to any skid steer and delivers 5 to 250 GPM of water suppression directly over the ash zone during cleanup.

Learn More →

FyreBx

LandBx: Site Dust Suppression

Active clearing and burn sites generate dust from tracked equipment, vehicle traffic, and dry soil exposure. The LandBx handles site-wide dust suppression on the same skid steer you are already running — no dedicated water truck needed.

Learn More →

How to Get a Merris Running on Your Site

Tell us about your clearing job

Call 770-433-2670 or fill out the form below. Tell us your material type, your volume per site, and how many sites you run per year.

We spec the right model

We match your volume and operation to the WX-5 or WX-8, walk through the cost comparison for your specific numbers, and confirm permit requirements we have seen in your state.

We deliver, set up, and train your crew

The machine is delivered to your site. We commission it with your operator and do not leave until the first burn cycle is complete and your crew knows what they are doing.

Every day your crew hauls debris off a site, that cost is coming directly out of your margin on that job and every job after it. At $55.80 per ton, a 100-ton site clears at a $5,580 disposal line item. At $21.76 per ton with the WX-8, that same 100 tons costs $2,176. The difference does not require a big volume. It requires one machine.

or call 770-433-2670 — Monday–Friday, 8am–5pm ET

Your WX-8 is on-site. The excavator feeds the firebox. One operator manages the burn. By the end of the shift, 60 to 70 tons are gone — not hauled, not stockpiled, not someone else’s problem. The ash from a full day’s burn fits in two bucket loads. The site is clear. The next crew moves in on schedule. And the disposal line on your job cost reads $21 per ton instead of $55.

That is what the WX-8 changes. Not the equipment. The math.

Parts in Stock. Engineers on Call. No Overseas Wait.

Every machine we sell is backed by US-stocked parts out of our Smyrna, Georgia facility. Not a backorder form. Not a six-week lead time from a factory in another country. When something needs replacing, we ship it.

Beyond parts, you get direct access to the engineers who know these machines — not a call center reading from a manual. We have been doing this since 1973. That means we have seen every problem these machines can have, we know how to fix them, and we have the parts to do it.

US Parts Inventory

Common wear parts — refractory panels, blower components, hydraulic components — stocked in Smyrna, GA. Ships same or next day.

Direct Engineer Access

When you call, you reach someone who knows the machine. Not a ticketing system. Not a callback queue. A person, on the phone, who can diagnose the issue and tell you what you need.

On-Site Setup & Training

We come to your yard. We run the machine with your crew. We don’t leave until it’s running right and your operators know what they’re doing.

Nationwide Field Technicians

A network of insured field technicians across the US. If the problem can’t be solved over the phone, we put someone on it.

Since 1973 — 50+ years of knowing exactly what breaks and exactly how to fix it.

Common Questions About Air Curtain Burners

Do I need a permit to operate an air curtain burner?

In most states, yes. Temporary use typically requires a burn permit from the local fire marshal or state forestry department. Longer-term or stationary use may require Title V air quality compliance. Requirements vary by state, county, and proximity to structures. We have sold and commissioned Merris units across the country and can tell you what permit process other contractors in your state have gone through. Call us at 770-433-2670 before you buy.

What is the difference between an air curtain burner and open burning?

Open burning is uncontained combustion — smoke, particulates, and gases escape directly into the air. An air curtain burner uses a high-velocity air manifold to force secondary combustion at temperatures above 1,800°F. That secondary burn re-combusts the particulates before they can escape. The visible result is near-smokeless operation. The regulatory result is EPA 40 CFR Part 60 compliance.

Can I burn stumps in the Merris WX-5 or WX-8?

Yes. Stumps, root balls, and large-diameter logs are standard material for both models. The 6′3″ door opening on both accepts most material without pre-processing. Very large stumps may need to be split before loading. There is no restriction on green or wet wood — moisture affects burn rate but not compliance.

How much ash does an air curtain burner produce?

Approximately 98% volume reduction. A rough benchmark: 5,000 tons of debris produces approximately 3 tons of ash, roughly 6 cubic yards. The exact ratio varies by material density, moisture content, and burn conditions. Ash can be spread on-site, amended into topsoil blends, or under specific conditions processed as biochar. It is not classified as hazardous waste from clean wood burning.

What is the difference between the WX-5 and the WX-8?

Burn rate and firebox size. The WX-5 processes 3 to 6 tons per hour and weighs 18,000 lbs. The WX-8 processes 6 to 9 tons per hour and weighs 24,000 lbs. Both have the same 6′3″ loading height. The WX-8’s firebox is 8 feet longer, which means it accepts larger material and runs a higher burn rate without constant loading. The WX-5 fits 1 to 3 acre daily clearing. The WX-8 is built for production-volume corridor clearing.

How does the operating cost compare to a horizontal grinder?

At 5,000 tons per year, the WX-8 runs at approximately $21.76 per ton all-in. A comparably capable horizontal grinder runs approximately $85 per ton, and requires a dedicated mechanic, a service truck, and a carbide tip budget now running $15,000 to $20,000 per year. The grinder makes sense if you have a reliable wholesale mulch market. If your goal is disposal at the lowest cost, the WX-8 is $63 cheaper per ton.

Can the Merris be rented instead of purchased?

Screen USA does not rent equipment directly. If you need a rental unit, our rental directory connects you with rental providers who carry air curtain burners. Browse Rental Options →