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Preferred-FactoryDanbury, CT – Here at Preferred Utilities, we are celebrating the independence of the United States and the freedoms we enjoy as Americans. The entrepreneurial spirit of our forefathers echoes down to us through the beautifully brave words of their fateful declaration: life, liberty, and the pursuit of happiness. That was 1776.

Founded in 1920, we’ve been living the American dream here at Preferred ever since. We were there when America’s heavy manufacturing was once a source of national pride. Remember “Rosie the Riveter”  during World War II ? Remember the the huge factories that once shaped the skylines of cities like Cleveland and Pittsburgh? Remember when America produced more manufactured goods than any other country?Rosie the Riveter

A lot has changed since then. Manufacturing in America is no longer a source of national pride. The old factories are gone, and we’ve been surpassed as the world’s leading manufacturer. Why? Because manufacturers realized that cheaper labor existed overseas.

Preferred Utilities never left. We’ve weathered the ups and the downs: depressions, world wars, economic recessions. We stay in America because we believe in America. That is why we proudly place the America flag on our products. Every time we etch those words “Made in America” on a burner or a boiler product, we rekindle the fire of the American manufacturing spirit.

It hasn’t been easy or cheap–but that never stopped our forefathers from fighting for what they believed in. This attitude is no better described than in this letter from John Adams, to his wife, dated 2 July 1776:

“I am well aware of the Toil and Blood and Treasure, that it will cost Us to maintain this Declaration, and support and defend these States. — Yet through all the Gloom I can see the Rays of ravishing Light and Glory. I can see that the End is more than worth all the Means. And that Posterity will tryumph in that Days Transaction, even altho We should rue it, which I trust in God We shall not.”

Happy Independence Day! And God bless.

made-in-america

 

Be sure to check out Preferred Utilities’ contributing article to Today’s Boiler written by Robert Frohock, PE.

From 5 Things You Might Have Missed In NFPA-85″

“Reality isn’t always what you’d assume when it comes to boilers, their controls, and their plants. Several lesser-known aspects could prove useful, so take some time and crack the rest of the code.”

You can view the online version of the magazine by clicking this link (page 10).

Robert Frohock, P.E. is the engineering manager for Preferred Utilities Manufacturing Corp. (Danbury, CT). Find out more at www.preferred-mfg.com.

 

By David Eoff

Danbury, CT – In 1964, Preferred Instruments published an article in the Fuel Oil & Oil Heat magazine. During that time, draft controls were used primarily to control excess draft from tall chimneys and lower excess air to conserve fuel. (Heating oil was 25¢ a gallon in 1964!) Additional benefits included more reliable burner performance, reduced burner emissions, and increased safety by tripping a boiler off line if the draft turned positive.

Check out the first page of that article below.

Draft Control, 1964

Draft Control, 1964

Today, draft controls are still common on all types of boilers,  but for very different reasons. Namely, boiler construction. Since then, many more boilers were of brick-set construction, required to be run at negative draft or balanced draft pressure. Because the furnaces were not air tight, the furnace walls were kept cool by a constant stream of cool air drawn in by the slightly negative pressure of the furnace. Allowing these furnaces to “go positive” for even a short amount of time could result in damage to the boiler casing or injury to boiler operators. Boilers made in this era typically had tall stacks to induce a negative pressure (or draft) in the boiler, or induced draft fans. To control the negative pressure generated by a tall stack or an induced draft fan, stack outlet dampers were installed and controlled to maintain a setpoint typically about 0.1” negative pressure measured at the back of the furnace. Then as now, proper draft control was also important for flame stability and maintaining the correct fuel air ratio in the boiler.

There are still many balanced draft boilers in operation that require draft controls for the same reasons they did in 1964. However, even airtight forced draft boilers built today often need draft controls to help stabilize burners using flue gas recirculation for NOx control. Flue gas recirculation is often induced by the combustion air fan. If the stack draft is too negative, the forced draft fan will not be able to induce enough flue gas to meet the required NOx emissions. If the stack draft is not repeatable, the fan will induce varying amounts of flue gas recirculation that will make the fuel air ratio control unstable. Burners utilizing high flue gas recirculation rates, and ultra low NOx burners have narrow limits of flammability and require precise fuel air ratio control. The combustion controller can’t precisely control the air flow through the burner if the boiler draft is constantly changing.

Boilers that operate with excessively negative pressure will draft too much air through the furnace, resulting in poor burner turndown and poor efficiency because excess air cannot be controlled–especially at lower firing rates. When these older boilers are retrofitted with low NOx burners using flue gas recirculation, the high draft condition needs to be controlled because the recirculated flue gas is diluted by fresh air (called tramp air) that leaks through the boiler casing. The diluted flue gas is less effective at reducing NOx. To meet typical NOx guarantees, effective draft controls need to be installed, and the boiler casings often need to be repaired to reduce air leakage.

Boiler construction today is almost entirely different, but draft controls are still required in many applications for mostly different reasons. Boiler combustion chambers now are entirely steel encased and air tight. The burners always include forced draft fans sized to pressurize the burner windbox, the furnace, and sometimes even part of the stack. The boiler and breeching are designed to withstand this positive pressure without the need for cooling air.

Today draft controls are required to accurately maintain draft conditions in the furnace and compensate for changes in outside conditions including:

  • Changes in ambient air temperature
  • Changes in stack temperature as the boiler warms up or changes firing rates
  • Changes in wind velocity blowing across the stack
  • Changes in draft conditions caused by multiple boilers connected to a common breeching.

Precise draft control is required now because we expect the burner’s fuel-air ratio controller to hold excess air levels typically below 15% at high fire to conserve fuel. The fuel-air controller can’t effectively maintain low excess air levels when draft conditions are changing.

Just as importantly, modern low NOx burners are more sensitive than their 1964 counterparts. Ultra low NOx burners are extremely sensitive to draft conditions (and ambient temperature, stack oxygen, phase of the moon, operator’s attitude, etc.) Too much draft can cause the burner to run lean, become unstable, and flame out. Too little draft can cause the burner to burn back into the burner internals and damage equipment. Most burner manufacturers require draft controls be installed with their burners if any of the following conditions are present:

  • Boiler stack is taller than 100 ft. (sometimes 50 ft. is the limit)
  • An induced draft fan is running in the stack
  • Two or more boilers share a common stack

If your applications meets one of the above conditions and you don’t install draft controls, the burner manufacturer will offer little help if you experience burner stability problems during start-up. A typical response will be, “Install draft controls and call us if the problem persists.”

To meet the increasingly demanding requirements of modern low NOx burners, draft controls have become much more sophisticated.

–Draft range transmitters have replaced the diaphragms in direct-sensing draft controllers. This is an important advance because the sensing line and diaphragms in direct-sensing draft controllers were prone to fill with condensation and quit working. Transmitters have this same weakness, but are easier to install higher than the breeching tap to ensure they stay dry. Draft transmitters usually include filters to help reject boiler pulsation and transmit just the boiler draft. Once the draft signal is digitized, it is easier to manipulate in a digital controller.

–PID controllers have replaced proportional only controllers. Although the derivative component of the PID control is rarely used, the integral component helps the controller respond faster to quick load changes. Floating point, and gap PID controls utilize a lower proportional gain when the draft is close to setpoint to help eliminate controller oscillation during normal operating conditions.

–Firing rate is often used as a feed-forward input to the draft controller. During commissioning, the technician determines the best draft damper position at 20%, 40%, 60%, 80%, and 100% firing rates. During quick load changes the draft controller monitors the burner firing rate and quickly moves the stack damper to these predetermined positions. As the firing rate begins to level out, the PID controller takes over again to trim the damper position to hold the draft setpoint for that load.

–Modern draft controllers have an adjustable start position—a separate damper position or draft setpoint used only for burner lightoff. If the technician is fighting an unstable pilot, he can position the draft damper or draft setpoint where he needs it to ensure a stable pilot flame and reliable main burner lightoff.

–A digital draft controller can generate a high or low draft pressure alarm, a low draft pressure shutdown contact to the burner management system, and can communicate digitally to a plant-wide control system.

Although positive pressure boiler designs have reduced the need for draft controls, the sensitivity of low NOx burners has actually increased the use of draft controls in recent years. As burner performance standards for low excess air, low NOx operation have increased, the performance requirements for draft controllers have increased proportionately. As the inset article at the beginning of this post shows, Preferred Instruments was one of the earliest providers of boiler draft controls. Today, Preferred Instruments continues to manufacture the most advanced draft control products available to handle any draft control application.

The JC-22D stand-alone draft controller interfaces with most burner management system and combustion controller to safely monitor and control furnace draft in virtually any application.

The Preferred JC-22D

JC-22D 

The JC-22D stand-alone draft controller interfaces with virtually any burner management system and combustion controller to safely monitor and control furnace draft in virtually any application.”

 

BurnerMate Universal

The BurnerMate Universal boiler controller incorporates burner management, combustion control, feedwater control, and draft control for complete boiler control in one easy-to-use package. The BMU incorporates all the draft control functions of the JC-22D. Because it is integrated with the other boiler control functions, the only field device required is a draft transmitter and draft damper actuator.

The BurnerMate Universal

The BurnerMate Universal

 

Danbury, CT — An extremely important, but often overlooked component of the back-up generator system is the Fuel Oil Delivery system. Like a silent sentinel, the fuel oil delivery system’s mission is to supply and constantly replenish diesel fuel to the generator day tank(s). It is therefore critical to perform regular maintenance and inspections in order to ensure reliability and trouble-free operation.

semi-automatic-pump-set

Semi Automatic Transfer Pump Set

The modern Automatic Fuel Oil Transfer Pump Sets, such as the Preferred Utilities Semi-Automatic Fuel Oil Transfer Pump Set, are state of the art systems which incorporate microprocessor-based controllers that monitor and control transfer pumps, return pumps, fuel tank level gauges, and tank leak detectors.

 

A typical system consists of a bulk fuel oil storage tank, duplex fuel oil transfer pump set (two 100% pumps, one for back-up) with control panel and fuel oil day tank(s).

In addition, many systems incorporate a fully automatic Fuel Oil Filtration system such as the Preferred Model PF to remove water, suspended rust, dirt and other contaminants in order to maintain the quality and purity of stored diesel fuel.

Fuel Oil Filtration Set - 2011

Preferred Model PF – Fuel Oil Filtration

Each component of the system requires a regular maintenance routine for optimum performance and longevity.

The optimum maintenance frequency would depend on the owner requirements, however the following is a suggested inspection and maintenance guidelines.  It is highly recommended to obtain a service agreement from the equipment manufacturer (if available) to perform maintenance at regular intervals. As always, refer to the manufacturer’s operation manuals for specific information on performing routine maintenance.

Weekly

Check Day Tank Fuel Level
Check Fuel Sentry Level Monitor for main storage tank
Check Storage tanks for water
Test Day Tank Level Switches
Test Automatic Pump System operation

 

Monthly

Check Pump set fittings and connections check for leaks
Check Pump set motor and pump mounts
Check Pump set strainer baskets
Check Fuel Oil Filtration set strainers and filters
Test All System Leak Detectors

 

Annually

Perform Complete Fuel Oil Handling System  Preventative Maintenance, Inspection and Systems Check
 

Carrolton, Texas — By David Eoff

It seems the new buzzword for our industry is Mission Critical. It’s the name of a trade magazine that caters to data centers. It’s also a term marketers use when they want to impress upon people that their equipment is installed at important facilities.

Preferred Utilities recently did a fuel oil project at a building that might be termed mission critical. This building will house the airline communication center (ACC) for one of the largest airlines in the country. The FAA requires that airlines be in constant communication with all their active planes at all times.

If they lose communication with a plane, that plane can’t fly. If it’s in the air, the plane has to land. If the airline’s ACC loses power, all their planes are immediately grounded. Losing communications with aircraft would require the airline to ground its fleet, resulting in a huge negative impact across the national airspace system.

Emergency Generator

The building that houses the ACC is on grid power. But it also has three generators, each with it’s own over-sized belly tank. The airline wanted this building to be tornado resistant, so the generators, belly tanks, and fuel supply system is all below grade. We provided Model 3 fill boxes so even the fill lines for the belly tanks are underground.

The generator to the left is one of three that can provide power for the building if the grid power fails. The Preferred PWC-based fuel controller provides tank gauging, leak detection, and overfill protection for the belly tanks for the three generators.

The image to the bottom right shows tank 1 being filled during final construction of the building. The Preferred system provides tank volume display at the fill port, as well as an overfill alarm at 85% full, and will shut off the fill line at 95% full.

Underground Fill Tank

Each generator has enough fuel to power the building for at least 24 hours. In addition, the airline pays a steep premium to be high priority for fuel delivery trucks. Their priority level is just below local hospitals in an emergency. The facility people have my cell phone number too. I live 20 minutes from the building and will respond if something goes wrong.

But who says that mission critical systems can’t be pretty, too? In addition to being tornado resistant, the Preferred Model 3 fill boxes can be hidden behind mulch and shrubberies to offer an aesthetically pleasing appearance. Look at the photo below if you don’t believe us.

 

Underground fill tank
 

In case you haven’t heard, we recently showcased our new BurnerMate Light at the 2014 AHR Expo.PMC-004

 

BurnerMate Light

BurnerMate Light

PMC-004The BurnerMate Light is an economical, state-of-the-art microcomputer-based burner management system with built-in first-out annunciation and combustion control designed for a single burner boiler or process heat application.

Meant to provide a scaled-down, economical alternative to our powerful BurnerMate Universal system,  the BurnerMate Light offers standby, purge, low fire ignition, main fuel light off, and release to modulate sequencing for oil and gas fired burners.

 For more information on this fully UL approved product, check out the full product page.

 

 

 

 

Preferred Utilities Provides Power to Abington Memorial Hospital during Storm

When Winter Storm Derby knocked out power across much of Pennsylvania, Abington Memorial Hospital continued operating thanks to emergency back-up generation systems provided by Preferred Utilities Manufacturing Corporation.
Abington-Memorial-Hospital

Abington Memorial Hospital

Danbury, CT — Power outages caused by Winter Storm Derby forced Abington Memorial Hospital to rely on emergency back-up systems. Thanks to the emergency fuel systems provided by Preferred Utilities Manufacturing Corporation, the outage did not affect care and the hospital remained fully staffed throughout the storm.

Dr. John J. Kelly, hospital chief of staff, told local news, “We’re in good shape.” When most local schools and residential complexes found themselves without power, the Abington Memorial hospital continued its critical mission thanks to its emergency generation back-up plan.

According to NC10.com, PECO Energy, the largest power provider in the Philadelphia region, assessed Winter Storm Derby as the worst winter storm outage ever. At the height of the storm, more than 600,000 customers were without power.

Dr. Kelly explained that the hospital found itself in good shape because it had planned for contingencies during events such as snow storms. In the event of lost power, the hospital knew that it needed an emergency generation system that would work in a time of need—because for a hospital, the availability of electricity can be the difference between life and death.

In order for emergency generators to work properly, they needed a reliable delivery system to keep the fuel oil pumping during emergency situations. Abington Hospital was well

Fuel Oil Pump Set and Day Tank

prepared for such an emergency situation thanks to a series of fuel oil products provided by Preferred Utilities, including: underground storage tanks, tank gauges, pump sets, day tanks, and boiler fuel delivery systems.

The underground storage tanks keep large amounts of backup fuel ready in case of emergencies. The pump sets provide fuel to the day tanks, where back-up fuel is ready at all times.

For mission critical applications such as emergency diesel generators and dual-fuel boilers, Preferred recommends that at least four hours-worth of fuel is immediately available via the Day Tank without activating the transfer pumps below. Abington Memorial Hospital utilized such a standby back-up fuel system.

Thanks to these products, Abington Memorial Hospital continued providing critical care to local residents during the storm—and they did so with full confidence that their fuel oil system would work when they needed it most.

Automatic Fuel Oil Transfer Pump Set

Preferred Utilities is the single-source umbrella for all mission critical needs. Services include customized engineering, consultation, installation, and scheduled maintenance.

Products include fuel oil handling systems, boiler equipment, burners, nuclear components, flow modeling services, and more. Our products can be found in commercial, institutional, industrial, and nuclear facilities.

 

 

When thousands of exhibitors and visitors descended on New York City for the 2014 AHR Expo, many of them weren’t prepared for the sudden snow storm that blanketed the streets of downtown Manhattan.  Preferred Utilities, however, came well prepared–and stirred quite a buzz by bringing several big items to the big apple.

Preferred Utilities debuted its new Advanced Performance Inject-Air Low NOx Axial Flow Burner (API-AF). This burner includes Preferred’s first packaged burner unit for 4MMBTUH-20MMBTUH applications.

API AF outside

API-AF Burner

By producing an exceptionally stable flame at all firing rates, the API-AF offers the same high efficiency, low emissions, fuel variety, and ease of maintenance of the original API burner–just in a smaller, more robust package.

API AF inside

API-AF Burner (open)

Included in the API-AF package is the new BurnerMate Light controller. Boasting UL approval, the BurnerMate Light provides an economical, state-of-the-art microcomputer-based burner management system with built-in first-out annunciatior and combustion control for a single burner, boiler, or process heat application.

BurnerMate Light

BurnerMate Light

Preferred Utilities also made a splash with its new Waterproof Pumps – an innovation spurred by Hurricane Sandy. The flooding in areas like New York and New Jersey emphasized the need to rethink mission critical infrastructure. Preferred developed the Waterproof Pump to operate uninterrupted during flood events, ensuring the safe supply of fuel for emergency generators and boilers.

WP Waterproof Pump

 

 

Also at the show: Preferred’s new Fuel System Controller (FSC). The FSC is Preferred Utilities’ next generation programmable logic controller with features specifically designed for critical data center and health care backup generator fueling systems.  FSC controllers automate fuel oil pump sets, suction integrity test, leak detection monitoring, generator day tank level control, day tank return pumps, main tank filtration/chemical treatment skids, multiple main tank motorized selector valves, tank gauge integration, tank truck off-loading , and much more. The FSC distributed control architecture avoids common mode failures. Each FSC has an independent power supply, CPU and I/O . Multiple FSC controllers communicate over a masterless, electrically  isolated, dual redundant network.

If you need to rethink your mission critical strategy–or if you would like further information on any of these new products–please contact Preferred today!

(203) 743-6741

 

Everything You Need to Know about the Preferred Pyroscope

When a submariner peaks into a periscope, it allows him  to survey his surroundings for potential dangers. When an engineer peers into a pyroscope, it allows him to inspect his boiler for potential combustion problems.

For frequent visitors to our site, you might have noticed a few changes. First off, we changed our look and we started a blog: The Preferred Pyroscope. Dedicated to serve as the go-to place for industry information,  we have one goal in mind by starting this blog: we want to help combustion engineers make informed decisions.

What should I expect?

If I were you, I would bookmark this page right now. We will use this blog as a spot for news, announcements, case studies, white papers, Q&A for users in our industry, and as a general source for expert information. This will be the best place to go for discussions on mission critical systems, combustion engineering, instrumentation, fuel oil handling and more. Plus, you can keep up with what we are doing. Did you see our post about our upcoming involvement with the 2014 AHR Expo?

What does our mission statement mean: Helping combustion engineers make informed decisions?


We want to help you, the engineers, make informed decisions. Whether that is giving you a deeper background into our products, insight into the industry, white papers, Q&A’s, or case studies, we want to help you be successful!

I will also be posting my thoughts on what’s happening in the industry, and I hope that this will provoke others to share their thoughts. After all, that’s what makes this industry such an exciting one to be a part of—and we value your opinion.

Who is behind this blog?
My name is Justin O’Donnell and I am the Marketing Manager at Preferred Utilities. I am based out of Danbury, CT and am a graduate of Pensacola Christian College in Pensacola, FL.

While I will be assisted by my coworkers with Q&A’s and bringing the experts in our industry to the forefront of conversation, I will be managing the day-to-day activities of the blog. Please feel free to leave comments and questions. We will be regularly monitoring it!

Did you know creating a connection with a company creates a better experience for you as the consumer? We invite you to make a resolution this year to stay connected with Preferred Utilities. Join in the conversation on our blog, follow us on Twitter, sign up for our newsletter, friend us on Facebook, find us on LinkedIn and YouTube.  

 

Side panelFood Processing Plant Saves Money by Burning Alternative Fuel

 

Many processing plants produce large amounts of waste water, causing plant owners to rethink their energy use strategy. In 2013, a mid-western US food plant found a way to use its own waste water as an alternative energy source.
When the city of Janesville, WI began constructing an anaerobic digestion system at its waste water treatment facility, the city created a contract to sell conditioned biogas back to the food plant.
Using its own conditioned biogas, the food plant unlocked the ability to burn self-produced alternative fuel. But in order for the project to be a success, the plant needed a combustion system capable of handling such a unique demand. Based on prior success with a similar plant., the plant owner’s turned to Preferred Utilities and a team consisting of Leidos Engineering, LLC and American Boiler.

 

Preferred Utilities designed and supplied a complete combustion system, including an API-800 Burner, a bio/natural gas mixture piping train, and a proprietary burner management/combustion control system.
The system was designed to burn either natural gas alone, or a mixture of preferential biogas and supplemental natural gas. Because digester gas contains sulfur and water, Preferred fashioned 316 stainless steel for all burner and piping components to resist corrosion. The combustion system’s startup and operation procedure is governed by a BurnerMate TS burner management/combustion control system.

 

The system consists of Preferred Instruments DCS-III digital controllers and a GNE 5004-M-85 Flame Safeguard module. The plant now employs a full metering combustion control strategy with FD fan, VFD control, and oxygen trim. The combustion air demand is determined based on the sum of the combustion air requirements established by the inputs of both the natural gas and biogas flow rates.

 

The combustion system now fires a natural gas/biogas mixture, with priority given to biogas based on availability established by supply pressure, thus maximizing fuel cost savings for the food processing plant.