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Hellcat: Lochinvar’s Latest Innovation

For over a decade, the Lochinvar CREST has been an efficient and reliable source of hydronic heat.  The product line has been improved over the years to take advantage of new technologies and components.

Past significant improvements include but aren’t limited to redesigning combustion air systems to utilize a single fan, improving the heat exchanger to allow greater heat transfer, and upgrading the controls for greater connectivity.

The latest innovation is the Hellcat combustion control system. This field-proven (more on that later) option adds continuous O2 monitoring and adjustment (aka O2 trim) to improve operation. A common challenge for peak condensing boiler operation is maintaining the proper fuel-to-air ratio, especially considering the wide range of ambient conditions we experience. Excess oxygen in natural gas and LP combustion prevents a boiler from condensing and capturing 10-12% of energy an owner paid for. Some systems just accept a certain amount of variability in operation. However, if a boiler is to constantly maintain peak performance, the adage of “measure to manage” must be applied. Unlike very large industrial boilers, no cost-effective opportunity for adaptation and improvement existed for smaller commercial-sized systems until now.  The Hellcat system continuously monitors combustion and adjusts to maintain optimum operation.

Given that heating plants are a CRITICAL system in our region, extensive field testing and proving is a requirement before Mulcahy will recommend any product to our customers. Mulcahy was involved in an extensive Twin Cities metro area field test installation of the Hellcat system that was continuously monitored over an entire heating season.

The 1.5 million BTU/hr input natural gas sealed combustion boiler had no interruptions of operation despite the wide range of air temperatures and density (more important for combustion control). How wide a range you might ask? The Hellcat system adjusted flawlessly over the equivalent of a 7000 ft range in altitude changes without adjustment. (The total range of operation is larger; we are just reporting what we observed). To put this in perspective, a normally aspirated internal combustion would lose 20-25% of its output power and require changes to the fuel input to keep running. Modern car engines can maintain fuel/air mixture ratios, but a power drop still occurs. The Hellcat system maintained full output capability AND tight combustion control. It is better than your car.

As stated before, heating plants are a critical building system in our region of the country. They are also a significant operating cost to building owners and the Lochinvar CREST with Hellcat control checks all the right boxes. Your local experts at Mulcahy would love to be a part of your next system.

For a more detailed description see https://www.lochinvar.com/products/commercial-boilers/crest-with-hellcat-combustion-technology

Lochinvar Crest

Land of 10,000 Links

Written By: Jeff Bennett

The North Star State truly does love golf! Year after year, Minnesota ranks in the top 10 in both golfers per household and golf courses per capita. Because of our love for the game, I thought it would be fun to share two of the amazing courses Minnesota has to offer. Everyone knows about Hazeltine National, but there are some great courses out there that have proven to be a fun challenge without breaking the bank. I’ll be highlighting one local course and also a resort about three hours up state in the Iron Range.

Braemar Golf Course – Edina, MN

In the spring of 2019, the city of Edina opened its new 18-hole Braemar Golf Course designed by Richard Mandell. The new course replaced the original 27-hole facility, giving the golf holes more space. It also allowed the city to expand wetland areas and restore over 30 acres of oak savanna. After almost three years of work, the new Braemar 18 is a beautiful yet forgiving golf course for people of all skill levels.  “Width for strategy has always been an element of my philosophy, going back to the nineties,” said Mandell.

On several holes Mandell has also employed central hazards, which emphasize the shot choices available. At the par-five fourth, for example, golfers can either choose a direct route to the left of a series of central bunkers or take the safer, but longer, high route to the right of them. This second option also rewards well-executed shots with a kick down the hillside towards the green. “The hazards are there not to punish golfers, but to challenge them to think their way around the golf course,” said Mandell. Braemar will prove to be one of the best courses for the money, especially when applying the Edina resident discount.

Braemar Golf Course – Edina, MN


Giant’s Ridge Resort – The Quarry and The Legend Golf Courses – Biwabik, MN

Giants Ridge, home of two Jeffrey Brauer-designed courses, has long been considered one of Minnesota’s best resort golf vacation destinations. Few other golf facilities in the nation can claim more than one course in Golf Digest‘s “Top 100” list like Giants Ridge can. Using the double play deal, I like to start with The Quarry golf course in the morning.  The Quarry will be one of the most challenging golf courses you will ever experience, and the lunch included in the deal will give you a much-needed break to regroup. The more forgiving Legend golf course is next, offering wider fairways and less required hazard carry.  The par-three #17 (pictured below) is The Legend’s signature hole, and it might be the most beautiful par-three in the state. After golf, head back to the Golf Villas to enjoy the evening and recall the struggles of the day. Dinner on your deck with golf friends overlooking Lake Wynne is the perfect finish to amazing day of golf.

The Legend Golf Course #17





Slashing Harmonics $aves

It is obvious how a variable frequency drive (VFD) saves energy and money by operating a motor at a reduced speed. Beyond just the reduction in power savings, VFDs with their inherent soft start and ramping can save in other ways such as equipment wear and tear. There is a new and exciting way VFD’s can impact building energy use beyond the piece of equipment it operates. It has to do with building electrical harmonics and how a building consumes electricity.

Electricity usage is different than other utilities used by a building. Water and natural gas consumption are directly measured. A given device that uses less of the resource to perform the desired output (i.e. more efficient) will cost the building owner less. An individual meter could be installed to determine the specific cost of operation.

With electrical loads, the manner in which a device draws its energy impacts the cost of operation along with the actual load. A buildings total system is comprised of linear and non-linear loads which results in a total building current (i.e. what the owner pays for).  This total current is made of fundamental current + harmonic current. The fundamental current is useful work being performed while the harmonic current is in effect the inefficiency of the system. More non-linear loads = more harmonics = LARGER utility bills. (NOTE: ABB has several technical articles that go into much greater detail if want to learn more)

VFDs get a lot of attention because they are large non-linear loads and responsible VFD manufacturers such as ABB have developed products and tools to predict and mitigate the harmonics they produce.   It is the latest product from ABB coupled with their harmonic calculators that allowed a large medical complex to improve their overall bottom line by using ABB Ultra Low Harmonic (ULH) variable frequency drive.

Initial calculations predicted an unacceptable amount of harmonics even with the ACH-580 industry-leading harmonic reduction features. The ABB harmonic calculation tools evaluated various options including harmonic traps, line reactors, and 18 pulse input units. Through this evaluation process, utilizing the ABB-580-ULH was found to reduce the VFD harmonic currents by a massive 285 Amps while meeting the buildings loads. This load reduction not only positively impacts energy costs, but also system areas like distribution transformer lifespan and sizing, and back-up generator operation.

If you have any curiosity about HOW the ULH saves this $$$$ beyond the motors it serves, we’d love to have that conversation with you. Contact the VFD group at Mulcahy to learn more about this game-changing product.

ABB Harmonic Calculator


Typical Harmonic Reduction Technique Comparison


Harmonic Calculation Key Results for a recent project


Initial Harmonic Evaluation


Ultra-Low Harmonic Evaluation


ULH Impact
284 Amp (83%) Reduction !
40% THD Reduction!



Great people drive great workplaces.

We’re excited to announce that Mulcahy was once again named one of Minnesota’s 2021 Top 175 Workplaces by the Star Tribune. Top Workplaces recognizes the most progressive companies in Minnesota based on employee opinions measuring engagement, organizational health, and satisfaction. The analysis included responses from over 76,000 employees at Minnesota public, private, and nonprofit organizations.

Through a year of pivoting and adopting new methods to operate, the Mulcahy team has continued to deliver unmatched service, expertise, and excellence. We are proud of our team and the innovation and growth our shared values, culture, and leadership drive.

“Having Mulcahy Company named again to this award is a true testament to the absolute BEST employees in the HVAC industry. Mulcahy continues to be a leader in the market by taking care of the little things, the big things and everything in between. Mulcahy’s fun, collaborative, family atmosphere sets the tone for a great place that people want to work for.”

—Russ Beneke | VP of Finance

Water Heater Alternatives – Part 1

Mulcahy has a long history of supplying solutions to the universal building requirement of providing potable hot water. The most common source is the standard tank-style heater with a natural gas burner. Storing a large amount of preheated hot water allows for immediate access to the heated water, but like any approach, there are downsides. A couple examples are:

Downside #1

Constant Storage: The constant storage of heat results in constant losses of energy, especially during long periods of no use. The most common burner used in these water heaters is an atmospheric burner located at the bottom of the tank. Flue gasses rise through a large passageway in the center of the tank to transfer heat to the water. When the burner is off, the hot water in the tank transfers heat into the same chamber, heating the ambient air.

Downside # 2

Installation Requirements: The natural gas burner brings with it many inherent requirements, including a gas line and a path for the flue pipe. Tank-type water heaters can also get quite large and heavy. This can make the old, reliable method unworkable.

One alternative to filling the need of supplying domestic hot water involves changing the entire approach.

Change #1

Do not store hot water. Create it only when necessary. The losses of the tank and the concerns of a large volume of stagnant water are nearly eliminated. The space requirements are also reduced.

Change #2

Do not use natural gas as the heat source. Tap into the central hot water system for an efficient source of energy. The gas line and its requirements are removed along with the flue pipe.

One option for providing instantaneous hot water is a packaged system which includes the heat exchanger and necessary controls. These systems are a great alternative to large storage tanks and flue pipes. Heat sources can range from high-pressure/temperature-steam to a low-temperature/highly efficient hydronic system. The nature of the heat source will dictate the heat exchanger size and type. See some examples below.

We’re glad to use our experience in previous installations to assist you in sizing, selecting, specifying, and installing these reliable and efficient systems.

New ecocirc® 20-18 and ecocirc+ 20-18

Bell & Gossett has long had a history of innovation and continuous improvement by taking advantage of new technologies and applying them to even the smallest products. Following the B&G “System Approach”, these new technologies are done to improve hydronic performance rather than doing things just to look flashy. New motor technologies and low-cost programmable controls have been the largest sources of improvement in recent history. Electronically Commutated Motors (ECM) have an inherent efficiency advantage over AC induction motors and are built to be operated in a variable speed mode.  However, this technology by itself does not improve a system. A pump must have some controls to determine the proper speed at which to operate. Not all systems are the same, so adjustability and control scheme options quickly become a requirement. The latest B&G pumps have all these qualities available to not just the larger-horsepower pumps, but the smallest as well.


Bell and Gossett is excited to announce the launch of the new ecocirc® 20- 18 variable speed ECM smart circulator. The ecocirc 20-18 and ecocirc+ 20-18 are the newest generation variable speed ECM smart circulators, providing a superior product for both heating and cooling and potable water applications including residential buildings, domestic hot water systems, underfloor heating systems, and more.


The ecocirc+ 20-18 model allows for wireless connectivity directly to a smartphone for full control. The ecocirc 20-18 can replace at least 70 pumps currently in the market, leaving no concerns for finding a suitable replacement on the job site. Features and benefits include:

For more information, visit https://bellgossett.com/pumps-circulators/circulator-pumps/heating-cooling-circulators/ecocirc-20-18/#product-tab-overview

Where We Are Now – An Update from Rob Grady

Over the last six months the Mulcahy team has been working in a hybrid environment to serve you while keeping our team as safe as possible. We have been working diligently to modify our workflows in order to limit the disruptions that come from this model. I have never been comfortable with the term new normal; I believe we will get back to some semblance of what we were used to before COVID.  I would like to offer an update on what Jack Foster, Editor-in-Chief of Agency Sales magazine, dubbed more aptly as the new abnormal, a term I consider to be less permanent.

About 1/3 of our team has been working in the office, consisting of almost all our inside staff. The balance of our team has been working remotely around the Twin Cities and in our out-of-state offices. We continue to improve our infrastructure and processes to effectively serve our customers in this arrangement, helped by our new CRM and ERP systems launched at the beginning of the year. Improvements to these systems are ongoing through employee and customer feedback.

We have been fortunate so far (knock on wood) to avoid any illnesses from the pandemic to our employees and their immediate families. While there is increased risk to everyone since social restrictions were relaxed in June, the opportunity to have a fun and productive summer has been most welcomed. We as a company are now expanding on that opportunity with in-person meetings and events while following the guidance and rules issued by the state health department. We have leveraged technology like everyone else, but seeing people face-to-face has been a welcomed change for the team!

We are working to expand that opportunity with our customers. While we were disappointed in having to cancel our annual Technical Expo this year, we are planning a mixed in-person/virtual event at the end of October that will feature short presentations, prizes, and a few surprises! This will even include a Watermark fundraising opportunity to support our community, though the dunk tank won’t work this year! Our webinar series will continue, but we will include some additional elements to break up the monotony of the flood of invitations for these types of events (we are getting them, too).

Lastly, we wish to thank you all for your continued business. We have faced a lot of challenges in 2020, and I have received feedback from other parts of the country that those challenges have resulted in some serious hardships to our industry. While all of us have been affected in some way by the pandemic, we are humbled and grateful to continue to be able to serve our customers and manufacturers while keeping our employees safe and healthy. We hope you enjoy a safe and healthy remainder of the summer before the heating season kicks in and the temps drop!

Thank you for your business!


Rob Grady


Mulcahy Company transitions to be employee-owned through an employee stock ownership plan (ESOP)

Mulcahy Company, an Eagan, Minnesota-based company representing manufacturers of hydronics products for the heating and cooling and plumbing industries, transitioned to become a 100% employee-owned company through an employee stock ownership plan (ESOP).

As owners in the company, the Mulcahy team will be even more driven to provide the best solutions and customer service to its hydronics industry customers. “Our transition to an ESOP will enhance employee engagement even more as our team members have a real stake in the outcome and success of the company,” says Rob Grady, Mulcahy Company President.

Mulcahy will continue its commitment to providing unmatched customer service, technical expertise, and professionalism to its customers and manufacturing partners.

Mulcahy Company, Inc., founded in 1929, is a manufacturer’s representative principally serving the heatingcooling, and plumbing industries. Representing manufacturers of such equipment as centrifugal pumps, boilers, cooling towers, filtration systems, heat exchangers, tanks, piping systems, valves, instruments, motor control devices, solar energy products, variable speed drives, and numerous accessory items, Mulcahy is an industry leader in the Upper Midwest Region.

Mulcahy Company names Rob Grady as President

Mulcahy Company has appointed Rob Grady, current Executive Vice President, as the company’s new President.

Rob has 11 years of senior leadership experience in the manufacturer’s representative and mechanical equipment industry and has served the last six years as Executive Vice President at Mulcahy Company.

“It has been a great experience working with our outstanding Mulcahy team, manufacturing partners, and customers over the last six years. I am excited and honored to serve as President of this amazing organization,” says Rob.

“Having successfully converted to a 100% employee-owned ESOP, we wanted to realign our company’s organization to help continue to make us the best at everything we do. Rob has assured us that he will lead the company as a servant leader and will work to further the culture that makes Mulcahy one of the best organizations of its kind,” says Mark Gaetz, CEO at Mulcahy.

Mulcahy Company, Inc., founded in 1929, is a manufacturer’s representative principally serving the heating, cooling, and plumbing industries. Representing manufacturers of a variety of products required by these industries, such as centrifugal pumps, boilers, cooling towers, filtration systems, heat exchangers, tanks, piping systems, valves, instruments, motor control devices, solar energy products, variable speed drives, and numerous accessory items, Mulcahy is an industry leader in the Upper Midwest Region.

Burner Retrofit Success Story

A large St. Paul health and fitness facility had trouble maintaining a piece of equipment critical to their operation. Their decades-old cast iron section Burnham V11 3.9 million input boilers not only serve the space heating requirements, but also the laundry, domestic water, and pool heating loads.

The problem was not the heat exchangers, but the original natural gas burners made by a manufacturer that went out business a decade ago. The linkage-based burners needed constant attention impacting reliability and boiler efficiency. The mechanical contractor with the service contract could not reliably source parts and recommended that the burners simply be replaced and upgraded. Replacing the entire boiler plant was considered but deemed cost prohibitive and the interruption to operation unacceptable. The burners could be replaced one at a time without having to shut down the entire plant. The Mulcahy Company Industrial Group was brought in to consult and suggest various options.

The original two-stage burners were high-tech for their day but transitioning to new burners allowed the customer to take advantage of the latest in proven technology from Power Flame Inc. and Siemens Burner controls. The total combustion overall included:

The refurbished boilers will improve the overall boiler efficiency an estimated 2-3% at full input. In addition, the full modulation firing coupled with the new ability to adjust water temperature will add to the efficiency gains. As an added benefit to the project, the owner received substantial rebates to help offset the cost of the upgrades.

In the end, the owners and operators of the facility ended up with a highly reliable and efficient boiler plant that will serve them for years to come.