Extended Burn Technology (EBT) by Pacific Energy’s

Extended Burn Technology (EBT) by Pacific Energy’s

Extended Burn Technology (EBT) by Pacific Energy’s

Pacific Energy’s Extended Burn Technology

Extended burn technology allows you to enjoy the longest cleanest burns without turning a single knob. Remember how your grandpa would wake up in the middle of the night worried about the charcoals. The mother of a baby would be obsessed every hour about going to the wood fire to place another log on top.

Woman and baby by the fire

We all love a blazing hot fire. But what happens when we go to bed? We leave the house to work in the morning? We come back from work and need to make dinner? Or just enjoy the family? Or lay back on the couch? Pacific Energy solved all these items with the (EBT) extended burn technology.

But I had an old airtight stove that did just this

My old stove had a HUGE firebox, with spin-draft control, primary control and secondary air control. I would close them all down with a big load and I had no problem holding the fire overnight. Two years ago I listened to the complaints of my neighbours about my smokey chimney and purchased a new stove. I was hoping to have a long overnight burn and just the opposite happened. The new stove gives out more heat. Is slightly smaller but won’t hold the coals as long even at minimum settings. I rang my dealer and his answer was blame the new emissions certifications.

Emissions

A recap of an ideal burn cycle in fires

Fire BurnAn Ideal burn cycle should heat the load of fuelwood to gasification temperature (Stage 1), burn the volatile gases to extract their heat value and clean up the exhaust (Stage 2), then maximize the duration of the fire as the wood fiber burns down to its final, charcoaling phase (Stage 3).

 

The most oxygen-hungry of the three phases of a wood fire is (Stage 2). The temperature of the load approaches 280° and the wood resins begin to gasify. With a big load in a large firebox, the “bloom” of volatile gases that floods the firebox during (Stage 2) is considerable requiring a sizeable quantity of oxygen to burn and extract the heat value.

Your old wood stove

Closing down to airtight on your old stove starved the fire for air. This smoulders the burn and prolongs the duration. Your old stove could go so long between refuellings because those low, smouldering fires did not have enough oxygen in the firebox to consume the (Stage-2) bloom of volatile gases. The gases escaped up the flue, taking as much as half the heat value of that load of wood with them. Lost heat is not the bad news.  Smoldering causes excessive creosote formation in the flue, and complaints from smoked-out neighbours.

Clean air complaints

In 1988 complaints from smoked-out neighbours meant different regulators got involved to clean up the air. New emission regulations around the world required that new wood stoves consumed the gasified wood resins. Mainly accomplished through a process called secondary combustion. A second fire inside the firebox re-burns the exhaust from the primary fire. Secondary combustion in small fire boxes is easier than secondary combustion in big fireboxes. When a BIG load reaches (Stage 2), the “minimum” airflow required for secondary combustion can be substantial. Providing enough airflow to meet emissions standards during (Stage 2) burn presents a major engineering challenge and designers of large wood stoves.

Popular solution

The most popular solution is the incorporation of a “stop” in the design of the draft control. The draft can not be closed down below a certain point. While this method might get a stove through testing, there’s a big downside. With no “low” draft setting available, an abundance of combustion air is delivered to the fire even when it is not needed, causing faster than necessary fuel consumption during the other stages of the fire. This results in frustrated owners of large size stoves who can’t “hold” a fire as long as they might want to between refuellings.

Pacific Energy´s Extended Burn Technology patented solution

Pacific Energy’s Extended Burn Technology (EBT) is a patented solution developed while designing the large size Neo 2.5, Alderlea T6 and FP30 insert model. The engineers at Pacific Energy incorporated several of the same techniques used in their smaller models to extend the duration of each burn.

  • Continuous-bead welded fireboxes
  • Tight fitting loading doors to minimize unwanted air infiltration into the fire.
  • A resistant heat deflector for high-temperature burns
  • Amazingly complex designed and tested secondary burn baffle made of 304 stainless steel

Mindful of consumer complaints concerning the lack of low-end control built into many of today’s larger stoves, they introduced the patented Extended Burn Technology (EBT) device. The EBT delivers a burst of extra air to the fire only as needed to maintain secondary combustion during (Stage 2) of the fire.

 

Extended Burn Technology
1998: PE’s Patented “Series A” EBT Mechanism

Extended Burn Technology
2013: PE’s Patented “Series B” EBT Mechanism

The original Extended Burn Technology device incorporates a pivot plate, mounted so its base covers a “boost air” intake opening. The plate is pivoted by an actuator arm attached to a bimetallic coil, which turns the arm in response to rising firebox temperatures when the volatile gases ignite at the beginning of Stage 2 of the burn. As the coil heats up, the plate hinges open to uncover the intake opening and provide extra air to the fire. When the gases have been consumed and the firebox temperature returns to normal, the coil contracts, lowering the base plate back down to seal the opening and stop the extra airflow. The Series B device is driven by a predictable increase in chimney updraft at the beginning of Stage 2 due to the rise in exhaust temperature when the gasified resins ignite. The increased updraft draws a balanced pivot plate open, uncovering an intake opening to provide the “boost air” needed to ensure complete combustion of the volatile gases. Unlike the original EBT device, which delivers the boost air to the primary fire, the new device feeds the extra air to the secondary flames only. The operator retains control of the burn rate of the primary fire, and longer burn times are easier to achieve.

What is an overnight burn with extended burn technology

An overnight burn is not a burning fire. An overnight burn means having a clean glass door in the morning. A nice bed of coals. A warm stove ready to be lit up with very little effort. The best way to experience a real overnight burn is with Pacific Energy.