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Category Archives: Preferred Utilities

 

The EPA made changes to the 1988 Underground Storage Tank (UST) regulations back in 2015, but the changes have not gone into effect until a date soon approaching, October 13, 2018. According to the EPA, the changes to the UST regulations are because of new technology proven to be reliable and accurate and the wide variety of new fuels on the market.

There are four main reasons for the EPA’s changes to the UST regulations: 

·       Operating and maintaining UST equipment properly

·       Prevent and detect UST spills and Releases

·       Protect against groundwater pollution

·       Even standard for all UST


Below are some of the following new changes to the EPA regulations that must be completed by October 13, 2018.

1.       Secondary Containment, Interstitial Leak Detection, Dispenser Containment1

When installing or replacing UST and piping owners must install secondary containment. Along with secondary containment, the owner must place interstitial monitoring as spill monitoring in these new tanks and pipes. Every new UST must have an Under-Dispenser Containment (UDC) installed.

2.       New Minimum Training Requirements2

Each operator working with a UST must be trained on the equipment by the manufacturer. Class A and B operators must receive training before October 13, 2018, or within 30 days of returning to work responsibilities. Class C workers must be trained before October 13, 2018.

3.       Walk Through Checks and Tests of Equipment3

Every 30 days the following equipment must be checked and tested: spill prevention equipment, release detection equipment, containment sump testing, and release detection system.

4.       Updated Criteria for Storing New Fuels4

New regulations for UST storing new emerging fuels.

5.       Past Deferrals for equipment were Removed5 6

The old deferral system for emergency generator tanks, field constructed tanks (FCT), airport hydrant systems (AHS) and wastewater treatment tank systems has changed due to new technology giving operators the ability to correctly and securely monitor these tanks.

6.       Updated Codes of Practice7 

New and updated codes of practice.

7.       State Program Approval (SPA)8

The EPA now requires that your state follow the new updated changes made to the UST regulations, even if you are in Indian country.

For a comprehensive list of changes made by the EPA go to: https://www.epa.gov/ust/revising-underground-storage-tank-regulations-revisions-existing-requirements-and-new#compliance

For a more detailed breakdown of each change go to: https://www.epa.gov/sites/production/files/2015-07/documents/regs2015-crosswalk.pdf

These kind of changes blindside many facilities. Preferred Utilities can help. We provide expertise along with a wide variety of valves, leak detection probes, and tank monitoring systems that help facilities keep up to date with the new regulation compliance. Preferred Utilities’ full staff of knowledgeable engineers work to keep the best products available, so your facility stays safe, secure and compliant. 

For the full line of services and products Preferred Utilities Manufacturing Corporation offers please click on the link below or call 203-743-6741.

Preferred Utilities Manufacturing Corporation

 

 

References and Links

1. https://www.epa.gov/ust/secondary-containment-and-under-dispenser-containment-2015-requirements

2. https://www.epa.gov/ust/operator-training-minimum-training-requirements-and-training-options

3. https://www.epa.gov/ust/operating-and-maintaining-ust-systems-2015-requirements

4. https://www.epa.gov/ust/emerging-fuels-and-underground-storage-tanks-usts

5. https://www.epa.gov/ust/emergency-power-generator-ust-systems-2015-requirement-release-detection

6. https://www.epa.gov/ust/field-constructed-tanks-and-airport-hydrant-systems-2015-requirements

7. https://www.epa.gov/ust/underground-storage-tanks-usts-laws-and-regulations#code

8. https://www.epa.gov/ust/state-underground-storage-tank-ust-programs#which

 

 

Team members from our Danbury, New York, and Boston offices along with associates of Preferred Utilities got together on August 9th for the 7th Robert G. Bohn Memorial Invitational golf tournament. This tournament is hosted by David Bohn and Preferred annually to celebrate the life and successes of Mr. Bohn’s father, the late Robert G. Bohn.

 

A U.S. Naval Air Corps pilot, Robert G. Bohn graduated from Greenbriar Military Academy and Dartmouth College and joined the family business after WWII in 1947. President and CEO of Preferred from 1963 to 1995; he continued as CEO and Chairman of the Board until 2011.

Robert Bohn’s accomplishments at Preferred include acquiring three companies: the instruments division of General Controls, W.N. Best, and Rimcor. These companies provided Preferred’s instruments, controls, and combustion lines of equipment. He was also the creator of Preferred Engineering with a group of local engineers.

One of our favorite traditions here at Preferred is remembering Robert G. Bohn with a sport he loved, and honoring his memory as a gentleman, leader, colleague, and friend.

 

The Coen “AC” valve has been nearly irreplaceable because of it complicated, characterized design and expense – until now!

As just one of its capabilities, the Preferred Voluvalve directly replaced and exceeded the performance of the Coen “AC” valve at this recent project site.

The Voluvalve can be made to drop in as a direct replacement for a COEN “AC” valve or be used in a parallel positioning type control strategy as was utilized at this jobsite with our BurnerMate Universal Combustion Controller and Flame Safeguard System. 

Using a custom and proprietary drilled hole pattern inside the valve, it allows the valve to repeatedly, and accurately match the optimal efficiency flow rate, and fuel air ratio characteristics for any burner.

Designed and Manufactured in Danbury, CT USA and started up in the field, if requested, by our application engineers. Contact us for more information.

 

Are there any fuel oil handling systems that don’t need return pumps? Are there any advantages to not having return pumps?  While it is true that I have worked on system designs and executions that have not included return pumps, my general answer is “no,” there are not any advantages.  And there are many different functional reasons why, especially within Mission Critical and First Response handling systems.  The purpose of this white paper is to list several different uses for return pumps under various circumstances, and to demonstrate how every single installation can benefit from them.

 

We all know that return pumps are great for keeping things under control, even if humans seem determined to find a way to spill fuel—running supply pumps in “hand,” or opening valves that should remain closed, and preventing a day tank overflow.  This is the most basic function of a return pump, and by far the most popular reason for their inclusion in both older and more modern designs.

 

FUEL RETURN:  Sending fuel from a day tank, to a main tank

Fuel return is a return pump’s most basic function.  During typical, normal operation, the return pump will be a lonely piece of equipment, but will also be one of the important safety features within the entire fuel oil handling system (FOHS), potentially saving very significant environmental and financial damages.

 

On many basic systems, the return pump will only activate when a “high” level float switch is activated, or similar signal, from a Controller.  An improvement is to have the return pump interlocked with a “high” level switch, which will start the return pump even in the event the Controller is offline or disabled.

 

Be sure to size the return pump appropriately to the application.  Calculate the highest possible rate of fuel entering the day tank.  On multiple day tank systems, this may mean the highest flow rate possible from all supply pumps running simultaneously, while filling that one particular day tank, and no others.  The return pump should be sized at a significantly higher rate than that potential high-flow rate.  How much higher will depend on pump type, available flow rates, etc., but should be 150-200% of the highest flow rate possible from the supply pumps.

 

 

INSPECTIONS AND REPAIRS:  Emptying a day tank for repair or replacement

What if you find fuel in your day tank’s secondary containment?  After looking for the usual leaking suspects, such as a threaded connection, weld, valve, etc., you may come to the conclusion that your primary tank is leaking.  Whether you intend on inspecting the tank, repairing or replacing it, you will need to drain it first.  But, if you have only a top/side-mounted overflow, how do you get the fuel out?

 

A return pump makes this process much faster and less messy, sending the good, clean fuel exactly to where you want it—back into the main tank.  You are also eliminating potential problems with big, messy barrels, which will contaminate the fuel and cause you to dispose of hazardous materials, increasing the hassle—not to mention the expense—even more.

 

 

FUEL FILTRATION:  Cleaning ALL of the fuel, not just the fuel in the main tank

One of the most common reasons for emergency generators to fail to run is bad fuel.  The best way to prevent bad fuel is to filter it.  ALL of it.  This means polishing the fuel that is trapped in supply lines, return lines, and day tanks.  Generators get their fuel directly from their day tanks, but most fuel is only polished in the main tank!

 

Return pumps are great for circulating fuel.  Modern control systems can be programmed to run polishing sequences, including activating return pumps (and supply pumps) that will circulate the fuel through the day tanks and allow it to be cleaned at the main tank(s).  Running a day tank “turnover” sequence, in combination with a filtration/polishing sequence, ensures much cleaner fuel throughout your entire fuel system.  The best generators on Earth won’t run on bad fuel!*

 

*ALL Mission Critical facilities should be on a strict fuel filtration and polishing regimen (Please look out for other white papers about Filtration from Preferred Utilities).  In fact, any facility that requires a backup generator of any type has a responsibility to ensure, to the best of their ability, that the generator runs in an emergency.  That’s what they’re there for!

 

 

THERMAL MANAGEMENT:  Decreasing fuel supply temperatures for generators

Generators use diesel fuel oil not only for internal combustion, but also for cooling the engine’s injectors.  Less than half of the fuel that the generator draws from the day tank is actually used for combustion; the remainder of the fuel is returned to the day tank by the engine, and at a higher temperature.  As continuous running creates a continuous fuel temperature increase, this can adversely affect the performance of the generator, up to, and including, generator shutdown.

 

There are two main contributors to overheating a day tank’s fuel:

  1. Ambient temperature.  Perhaps the day tank is outside, or on a rooftop, in a warm climate, or all of the above.  If the fuel in the day tank is already at 95 degrees F, for example, it’s going to rise fairly rapidly when the generator engine starts.  Unfortunately, in places like California, many power outages occur during the hottest days of the year, due to excessive demand on the grid.
  2. Day tank size versus generator engine size.  A large generator engine paired with a small day tank will increase the day tank fuel temperature quickly, regardless of any other environmental conditions.  Local, state, or national code may inhibit the installation of larger day tanks.

 

Return pumps can assist in decreasing fuel temperatures for generators under both scenarios.  By simply circulating the hot fuel out of the day tanks, and replacing it with cooler fuel from the main tank(s), the generators will continue to run, and run more efficiently.

 

This fuel circulation can be automated.  The day tanks can be equipped with Resistance Temperature Detector (RTD) probes, which will monitor the day tank temperature.  When the day tank temperature reaches a pre-determined threshold, the RTD will signal the master control system (“Controller”), which will start a day tank cooling sequence.  We sometimes refer to a day tank cooling sequence as, “level bouncing.”  A level bouncing sequence would look something like this hypothetical example:

  1. RTD reports temperature threshold met on Day Tank 1 to Controller.
  2. Controller activates Day Tank 1 Return Pump.  Day Tank 1 begins to pump out.
  3. Day Tank 1 reaches “Supply-Pump-On” lower level, which creates a Call For Fuel.
  4. Controller turns Return Pump off.
  5. Controller activates Supply Pump, and opens Day Tank 1’s inlet valve.
  6. Supply Pump fills Day Tank 1.
  7. Day Tank 1 reaches “Supply-Pump-Off” high level.
  8. Controller deactivates Supply Pump.
  9. RTD monitors temperature, and…
    1. RTD reports temperature threshold met on Day Tank 1 to Controller, and sequence repeats… or…
    2. RTD reports temperature acceptable.  No action occurs.

Return pumps are useful for far more than just pushing fuel back to a main tank.  They are an integral part of any system and do not only save us from a messy cleanup and a lot of explaining, but also enable us to truly and completely clean a system, cool a day tank, or just do a more thorough inspection.

 

For more information, or if you have any questions, please contact:

 

Lee Carnahan

District Sales Manager, West

PREFERRED UTILITIES MFG. CORP.

209.890.9993 cell

LCarnahan@preferred-mfg.com

 

A linkageless control system uses a burner with individual servos to control fuel and air ratios, and provide more savings to the end user. This technology can cut boiler room costs and solve end-user headaches. Here are three reasons to choose linkageless controls:

  1. Higher efficiency: O2 levels may fluctuate, but will always return to position of highest fuel and electrical efficiency. In addition, turndown is often improved resulting in less cycling of the burner.
  2. Monitoring and communication: the system communicates via Modbus and reports on all functions. The main module monitors the positions of all fuel- and air-control devices. Any positioning error shuts the burner down safely.
  3. Automatic adjustments for ambient air and fuel changes: Linkage systems can cause major problems for technicians. Once all the linkage is set, the ambient air density may change, throwing the system off. In addition, instead of system readjustment every time there is a fuel switch, the positions of all servos are programmed and independent. This means that the system adjusts automatically to fuel/air ratio changes as well as fuel changes.

In a world of high electric and fuel costs, this technology is indispensable to the modern boiler room.

 

Top tier American college chooses Preferred Utilities as their partner in a major burner and controls retrofit project on their existing (700 hp) Johnston Boiler. With the installation of the dual fuel Preferred Utilities API-InjectAire burner, the college will reduce its electric consumption on this unit by more than 75% while increasing combustion efficiency by more than double.

With the new ability to have Low NOx 10:1 turn down on natural gas and 8:1 turn down on oil along with precise draft control, and O2 trim, greenhouse gas emissions will be significantly reduced along with wear and tear on the boiler.

We manufacture in the USA and provide single source responsibility for burners, fuel trains, combustion controls and factory start up.

 

RFO-headerDiscussions of sustainable energy don’t often include food flavorings. However, the same process that creates liquid smoke—the stuff you can buy at the grocery store to add a smoky flavor to just about anything—can produce liquid wood, a very environmentally friendly fuel.

You may not have heard of liquid wood because, until very recently, it was quite difficult to burn effectively. Preferred Utilities Manufacturing changed this.

Liquid smoke is part of a family of products whereby wood is converted from a solid into a liquid. Wood pulp is heated in the absence of oxygen during a process called pyrolysis. This produces bio-oil—or liquid wood.

Unlike petroleum or natural gas, liquid wood fuel is a 100% renewable resource: the wood used to create the fuel can be balanced by replanting new trees. Liquid wood is also carbon efficient because the replanted trees offset carbon emissions, which eliminates the need to purchase separate carbon offsets. As a result, liquid wood is 81 percent more carbon efficient than natural gas, and 88 percent more carbon efficient than petroleum.

Once it’s being properly fed to the burner, liquid wood behaves pretty much just like traditional fuel oils. This means that existing boiler equipment can be retrofitted for use with liquid wood, dramatically decreasing conversion costs compared to other biofuels.Green Oil

So why haven’t we seen the widespread adoption of liquid wood as a fuel oil? After all, the basic chemistry isn’t new—liquid smoke has been around for more than 100 years. Ensyn, an Ontario biofuel firm, has become adept at producing competitively priced liquid wood fuels, but very few companies have been able to offer reliable systems to burn these fuels, and none have been successful in the marketplace—until now.

Ranger-Brochure-ClipOne of the keys to burning liquid wood is the pump system that delivers the fuel to the boiler. Liquid wood has to arrive in the boiler at much higher and more specific pressures than natural gas or petroleum, and because it is highly acidic, the pipes must be high-grade stainless steel. This all requires advanced pumping and monitoring equipment, combined with the engineering chops to put the whole system into place. That’s where Preferred Utilities shines.

As a hybrid engineering/manufacturing firm, Preferred is uniquely equipped to devise and implement customized solutions to help commercial and residential properties including universities, colleges, hospitals, and more convert their boilers to liquid wood. Compared to other biofuels that can’t be retrofitted to existing systems, such as wood chips or pellets, the logistics and upfront investment of converting to liquid wood for heating fuel is quite reasonable.

But handling the fuel is one thing. Burning it? Another thing entirely. We’re talking about a substance that is 25% water with the consistency of lemon juice. Burning it effectively presents a significant challenge. That’s why Preferred Utilities developed the Ranger Combustion System. As of May 2017, Preferred Utilities burners are the only known burners capable of effectively and reliably firing liquid wood. There are several installations in Ohio, Vermont, and Maine currently burning this fuel with Preferred Ranger Burners.

Ranger,-Open,-Vignette-[web]

Liquid wood also presents an opportunity to go green quickly. It can take years to transition to carbon neutral, but a liquid wood conversion can be completed in a matter of months. We have found that in many cases this extraordinary fuel source can reduce carbon emissions by about 80 percent. For more information about the potential of using liquid wood at your establishment, contact Preferred Utilities at (203) 743-6741.

 

 

 

 
Automatic Fuel Oil Transfer Pump Set (ATPSF)

Automatic Fuel Oil Transfer Pump Set (ATPSF)

The Automatic Transfer Pump Set (ATPSF) is one of our best-selling products. Our customers love it for its reliability and rugged industrial construction. We consistently beat out our competitors because we build our products out of the highest-quality components. Behind each of our systems, you will find a team of engineers and technicians who are dedicated to getting you the best results possible. People. Products. Results.

Thanks to our new Flexible System Controller (FSC), we have added several exciting features to our  ATPS:

1. Redundant Communication

The FSC is masterless, and uses dual redundant, optically-isolated RS485 cables. RS485 cables eliminate hubs, switches, and repeater failure modes. Because both NodeNet cables communicate continuously, one cable can go down while the other continues communicating with no interruption. If any node fails, all the other nodes will continue to function.

As far as we are aware, Preferred Utilities is the only manufacturer offering this multiple failure backup system.

Sample System Diagram

Sample System Diagram

2. Faster Troubleshooting

FSC OIT Screen

FSC OIT Screen

Another feature of NodeNet communications is that it allows the operator to control or view any device, status, or alarm anywhere in the system from any touchscreen in the network. Because operators can see both digital and analog inputs and outputs from anywhere in the system, troubleshooting becomes streamlined, and much faster than it would be otherwise.

3. Distributed Controls

NodeNet communications provide the additional advantage of distributed control. The NodeNet system employs multiple distributed modular controllers, which are hard-wired to local devices. Even if both NodeNet cables are lost, local automatic control will continue. This modular aspect of NodeNet allows for maximum mission critical reliability.

4. Reduced Wiring Costs

The NodeNet communications network can reduce wiring cost significantly. The average number of wires per day tank (14 home runs) can be reduced to as little as 2 redundant communication cables in a loop between FSCs.

Distributed Controls

 

 

Energy Savings Calculator

The Advanced Performance Inject-Aire burner blends the best of both worlds: high efficiency and low emissions. In a day and age where manufacturers compromise quality and effectiveness, Preferred Utilities prides itself in challenging the status quo. We don’t do cheap. We don’t do flimsy. We build our equipment to last—in fact, some of our burners built in the 1960s are still in operation in New York City. That’s dependability.

When it comes to decision time, many customers find themselves struggling to pick between low emissions and high efficiency—but why should you have to choose? As an added bonus, our burners can pay for themselves in just a year’s time.

So just how much energy can your application save with an API Burner?

Download our “EnergySaver Payback v8.3” to find out.

Download: Energy Savings Calculator

 

PUMC_20130213_024

Danbury, CT – A boiler system functions as a critical component to the continuous operation of a facility.  The loss of a boiler can cause disruption of operation and significant loss. Thus, it is important to maintain safe, reliable, and efficient operation while minimizing any downtime of the boiler system.

A boiler system consists of many sub-systems working in harmony, such as the boiler, the burner and its control, boiler control including feed water and draft control, fuel oil handling system (if burning oil is required), water treatment, fuel gas booster system (for areas with low supply gas pressure) etc.These sub-systems are sometimes procured from multiple sources.  In order to deliver the safe, reliable and efficient service that the end user expects, it is advantageous to adopt a “full system integration” approach.

Possible Problems

A boiler system in general could have many modes of failures.  Failures in water level control have serious implications on the longevity of the boiler and in safety (the sudden inrush of feedwater to a baked-dry boiler could lead to a steam explosion). Water treatment failures can decrease the longevity and efficiency of the boiler. Boiler operators need to understand these dangers. Among all sub-systems, the burner system is by far the most sophisticated subsystem in a boiler system. The burner system has many modes of failure that require extensive training and/or experience for the boiler operators to fully understand.

When a boiler system is not delivering satisfactory performance to the end user, it is sometimes difficult to pinpoint the exact cause of the problem. The following example is used to illustrate this difficulty. Sometimes a burner makes a low frequency noise, often called a combustion rumble. The rumble could be a nuisance or discomfort to the operators and residents nearby, or could even cause damage to property. Potential causes of the rumble include, but are not limited to:

  1. The burner has poor stability at certain firing rates; or the burner’s window of operation is too narrow. This could be related to the design or manufacturing of the burner.
  2. The air/ fuel ratio is improper due to poor commissioning or lack of maintenance.
  3. The servos used by the burner control may have poor accuracy or repeatability.
  4. The linkage between servos and dampers may be loose.
  5. The system does not have oxygen trim to ensure consistent excess air levels. Any variation in draft, ambient temperature, fuel gas composition, building ventilation (affecting building inside pressure vs. outside ambient pressure), or wind speed blowing on outlet of chimney, can affect the amount of combustion air supplied by the fan.
  6. Lack of draft control.  Severe draft variation may cause the air/fuel ratio to go out of range.  This is definitely a challenge if the system does not have an oxygen trim system; it can be a problem even with an oxygen trim if the draft variation is too severe for the oxygen trim to compensate.
  7. The “acoustic coupling” between the burner and the boiler’s fire chamber and the subsequent space the flue gas flows through.
  8. The fuel gas booster could surge and cause the gas pressure to oscillate, beyond the pressure regulator’s ability to regulate.
  9. The boiler room’s ventilation system could be improperly designed. When windows and doors are shut, a significant negative pressure can develop in the boiler room, causing a drop in combustion air supply and air/fuel ratio.
  10. Fuel gas supply pressure and composition can fluctuate, especially if the fuel gas is from an alternative fuel source, such as land fill gas or, to a lesser degree, digester gas.
  11. Burner components may not work well together. For example, the gas regulator may be over-sized for the flow rates of the burner.

Problems with the Multiple-Vendor Approach

Fully integrated custom controlsWhen the subsystems are procured from many different vendors piece-meal (by the general contractor or the end user) and no engineering firm takes responsibility for integrating these subsystems, it may be difficult to identify the party responsible for correcting the problem. This often results in blame shifting among different parties, ultimately frustration for the end user.

For example: in a piece-meal approach, the burner may be supplied by a burner company, the controls may be supplied by a company that is solely dedicated to burner controls and knows little about the combustion behaviors of the particular burner. The specifications do not call for a draft control or oxygen trim, when in reality one or both of those may be required for the site conditions and requirements. The booster, if there is one for the job, may be supplied by yet another vendor, the commissioning may be done by a contractor, the ventilation system of the boiler room may not have been designed properly to avoid high negative building pressure.  The troubleshooting process itself is further complicated by the diverging interests of the different parties involved.

Sole Source Responsibility

The most important advantage of the full system integration approach is that the integrator must accept sole source responsibility. If the burner system does not perform, the integrator is responsible for correcting the problem. There is no blame shifting among different suppliers.XPlus

A burner system supplier that adopts the full system integration approach is inclined to build a long term relationship whenever it sells a job. The supplier would look at the specific conditions and requirements of the customer, and look for the best solution tailored for the job instead of chasing the latest trendy requirement in specifications. For example, it may be tempting to ask for a 12:1 or higher turndown from the burner system, but can the non-condensing boiler operate at 12:1 or higher turndown without condensation and corrosion problems?  Is 10:1 or 8:1 turndown enough for the job? In another example, does the system require a draft control device to work? Can the burner deliver satisfactory performance without the draft system?

A supplier adopting the full system integration approach would look at total costs of ownership (the fixed costs and the operating costs) for the boiler system, instead of focusing on the fixed costs. In today’s corporate procurement practices, too often the one responsible for buying the boiler system is not the one paying the energy bill, hence there is less incentive to consider the total costs of ownership.

For example, a burner capable of operating at 1.5-2.5% oxygen during the majority of its operation time can lead to significant savings in fuel costs.  If a vendor offers a burner system without use of  oxygen trim, is the burner operating at consistent excess air levels all year round? Does the lack of oxygen trim mean conservatively high excess air levels? In another example, a fiber mesh burner may be used to meet 9 ppm NOx requirements without FGR, but the additional costs of fuel due to the very high excess air levels (typically 8-9% oxygen dry in flue gas) and the costs of replacing filters and fiber mesh combustion heads need to be factored in when purchasing a burner system. In another example, a burner constructed with flimsy, low grade sheet metals may need frequent service and replacement parts, while a burner constructed out of durable steel can provide years of service beyond the normal warranty periods.

The “full system integration” approach requires an integrator to have in-depth understanding and strong product offerings in all of the following areas:

  1. Boiler controls. The boiler controls ensure safe and smooth operation (water level control, burner firing rate based on temperature or pressure, draft control if necessary). It should have the capability to manage the lead-lag control of multiple boilers to ensure the boilers are operating at maximum efficiency.
  2. Fuel oil handling systems (main tank, day tank, pump sets, filtration, leak detection, etc.)
  3. Burners–especially those designed for both high efficiency and low emissions at the same time. The end user should not be forced to choose between high efficiency and low NOx.  High turndown (such as 10:1) helps avoid cycling of the boiler, and low excess air minimizes loss of heat to flue gas. Use of FGR is acceptable, but the incremental costs of running a larger motor due to FGR should be factored in. Advanced designs of burners can achieve mandated NOx emissions with less, little, or no FGR (depending on the NOx levels required).
  4. Burner controls.  The burner must be equipped with the latest Burner Management/ Combustion Control Systems (BMS/CCS) to assure that safety aspects are in accordance with the latest requirements of NFPA 85 and CSD-1. When high efficiency or tight emissions are required,  an oxygen trim system should be included, and parallel positioning or fully metered control should be used in lieu of jackshaft. The combustion control and the servos should be designed to modulate the controlled fluids (air, fuel, FGR etc.) in a coordinated manner.  For example, if the air servo cannot move fast enough to be in sync with the fuel servo, then the fuel servo needs to be slowed down in modulation, and vice versa.
  5. Commissioning and maintenance.  The burner system is commissioned and maintained by qualified service technicians that are knowledgeable about all the subsystems.
  6. Technical support and spare parts. These should be available from nearby locations.

Preferred Utilities Manufacturing Corporation has earned a reputation for accepting single-source responsibility. We firmly believe in the advantages of full system integration. Compared to the piece-meal approach, the benefits of full system integration make the choice clear. If you believe the same way, please contact us about your next project.