Projects Balance IAQ, Comfort, Efficiency
Case Studies Highlight Custom Solutions to Individual IAQ Problems
From machine shops and warehouses to homes and health care facilities, IAQ is a major concern for many individuals. The following five projects demonstrate how contractors are working closely with customers to provide personalized, effective, and efficient IAQ solutions.
Contractor Creates a Healthy Home
John Williford of ComfortMaster Mechanical in Greenville, North Carolina, had a challenging project on his hands when his clients, who were building a state-of-the-art, high-efficiency home in hot and humid eastern North Carolina, started asking about IAQ.
“The Martins contacted me with a very specific list of concerns ranging from pet dander and allergies to odors and ventilation,” Williford said. “They had already decided on the Carrier Infinity System for heat and air but wanted more control over the quality of their air.”
The new home would include a commercial range hood in the kitchen, which would routinely exhaust as much as 1,200 cfm from inside the home, potentially creating negative pressure and a need for make-up air. As a result, outside air would need to be added back into the home to maintain balance and keep unfiltered air, moisture, and pollutants like radon and carbon monoxide from being pulled into the home.
“I read that radon gas is the number two cause of cancer, and I was concerned about pulling radon and moisture from the crawl space and VOCs [volatile organic compounds] from the garage,” said Tracy Martin, homeowner. “My husband is an engineer, and once he started studying some of the problems with indoor air, we became seriously concerned.”
Williford did some research and recommended the Healthy Home System™ by Field Controls LLC. He talked with Bobby Nelson, vice president of sales and marketing for Field Controls, who helped him configure the optimal system, and he also used the Field Controls’ Healthy Home iAQ App to help configure the components needed in the Martin family’s home.
“I was able to sit down and put together a package that would work best with my home to deliver and maintain air that is fresh, clean, and pure,” Tracy Martin said. “We were able to easily compare several options and select the one that best fit our goals, budget, and system.”
The Healthy Home System for the Martins’ home included a Healthy Home System Control, fresh air ventilation, a FlexMountUV™ over the A-coil, and the new three-in-one Trio, which combines two high-intensity UVC lamps, a MERV-13 high-efficiency air filter, and a proprietary PRO-Cell™ grid to neutralize toxic VOCs, odors, and smoke.
“The Martins were also concerned about ozone,” Nelson said. “The Healthy Home System is ozone-free.”
To ensure an adequate, reliable source of fresh air, Nelson recommended two fresh air dampers. The dampers are tied into the return via flex duct and automatically power open when the system requires fresh air. As the outside air enters the return, it is filtered, purified, and tempered before it enters the house. To accommodate the kitchen range hood, Williford installed an override switch that opens the dampers to balance the air in the home and quickly eliminate cooking odors.
In addition to the twin UVC lamps in the Trio, Williford installed Field Controls’ FlexMount™ UV lamps inside the air handler over the A-coil to keep the coil and drain pan clean and mold-free. Periodic filter changes and annual service is the only maintenance the system requires, and when it’s time to service the system, the mobile app automatically emails Williford.
Tracy Martin finds the air system makes a big difference. “The new-house smell has stayed with us,” she said. “The odors don’t linger; I don’t notice a smell when I’m done cooking.”
She also loves how clean the house stays. “We have a yellow lab; they’re notorious for shedding. With this system, I’ve noticed a definite decrease in fur and dander. In our previous house, I was vacuuming pet dander and dust daily. This system has significantly reduced the amount of pet hair and dust that’s around the house, and, of course, the amount of vacuuming I have to do.”
Medical Center Boosts IAQ with Ventilation
Built in 1980, the Turner Center in Springfield, Missouri, is a medical center that includes an urgent care center, pediatric and adult outpatient services, a pharmacy, and numerous medical provider offices. With facility additions over the years and the need for improved IAQ, CoxHealth approached Shannon McCall, lead engineer at Telios Engineering in Dallas, for help with a redesign.
To improve IAQ and save energy, McCall suggested the Governair Series WF air-handling unit with energy recovery and FANWALL TECHNOLOGY®, which uses 100 percent outside air for maximum ventilation. The Governair unit was installed in line with the outside air intake of the existing air handler and uses energy recovery wheels to condition incoming outdoor air, recovering energy from the building exhaust. The energy recovery ventilator (ERV) was selected both to improve the air change rates for the building and to compensate for a low existing chiller tonnage.
“Previously, the building was struggling to hold temperature in the summer,” McCall said. “The ERV is supplementing the chillers, and the building is now holding at a comfortable temperature.”
To overcome the additional static pressure caused by adding the ERV system, additional fan capacity was needed. The Governair custom air handler designed for this project uses a total of 18 FANWALL fan cells, which are installed in the ERV unit nine-wide and stacked two-high. “The FANWALL units’ ease of installation and minimal maintenance requirements also made them a good fit for this application,” said Gary Whittenberg, assistant director of engineering at CoxHealth.
The total ERV system is housed in Governair’s rugged Series WF cabinet, which features a fully welded, phenolic-coated, tubular steel framing system for maximum flexibility and strength. The assembled unit — which is 33 feet long, 16 feet wide, 12 feet high, and weighs 42,000 pounds — was shipped in two sections and assembled on-site.
Springfield Engineering Co., Springfield, Missouri, worked with Aaron Fields of local Governair representative Fields Mechanical Systems Inc. in designing the system and coordinating delivery. “We had just one day to set the unit sections on the rooftop,” Fields said. “Once the unit was set, we waited until the following weekend to tie the unit into the penthouse and bring it online. The facility was operating within a few hours after tying in the duct and electrical.”
“Since this unit has been installed, we’ve not had one complaint about odor or any complaints about lack of cooling,” said Gary Whittenberg, assistant director of engineering at CoxHealth. “The system recovers enough energy to supplement the existing system as well as provide 100 percent fresh air to the facility.”
Machine Shop Turns to Energy Recovery
To justify the expense of a million-dollar computer numerical control (CNC) machine, it had better be running. And, when an entire 11,000-square-foot machine shop is full of those machines, time is money — big money.
Rick Hennig, owner of Rite Engineering in Franksville, Wisconsin, knows this as well as anyone. At his enterprise, they tap, ream, mill, drill, and bore everything from plastic to titanium — all to aerospace specifications.
“This equipment costs a lot of money and makes a lot of money, but only if it’s running,” Hennig said. “The machines produce more than precision components, though; they make lots of heat, and the lubricant smokes.”
Over the past several years, demand for Rite Engineering products has increased, and Hennig has added more machines to his production floor. The shop’s existing HVAC system — a simple make-up-air unit and exhaust fan — couldn’t keep pace with the cooling load added by the new machines, so, on hot summer days, his machinists had to leave by noon because of the stifling heat and unhealthy air inside the shop. Fume hoods were not an option, so Hennig began searching for other options.
After reading an article in the Racine Journal Times about nearby Modine Mfg. Co.’s expanded capabilities in the HVAC market, he contacted the company to see if they could present a cost-effective means of improving conditions within the shop. Bob Fritchen, brand sales manager of unitary products at Modine, thought he might have just the cure: Modine’s Atherion®, a commercial packaged ventilation system. With its integrated ERV module, the Atherion is a high-efficiency, 100 percent dedicated outside air system (DOAS). The Atherion is designed to meet latest ASHRAE 189.1 and 62.1 standards for IEER, efficiency, green building, and IAQ.
“In addition to cleaning and conditioning the indoor air, our strategy was to transform all the heat generated by the machines from a liability to an asset, particularly during the long, cold heating seasons we have in Wisconsin,” Fritchen said. “We achieved this by exhausting the indoor air through the Atherion unit’s optional ERM, which reuses free Btu from the exhaust air — energy that would’ve been wasted by a simple exhaust hood — to preheat, cool, and dehumidify the ventilation air, depending on the season. Also, an oil mist eliminator filter was selected for the return air duct to protect the unit’s components and improve the quality of the exhaust air in the local environment.”
In 2012, with help from the professionals at Southport Heating, Plumbing, and Geothermal in Franksville, Wisconsin, the 15-ton (180-MBtuh) Atherion unit with ERM was installed on a frame on the west side of Rite Engineering’s main building. “The installation went smoothly,” said Mike Nuzzo, president of Southport. “We set the unit up and ran gas feed and electric to it. All hook-ups were straight-forward and installer-friendly. The biggest challenge was running ductwork while the shop was in full production.”
“The day after they commissioned the unit — the first full day of use — the air quality and temperature inside the shop were much better. It’s hard to describe, because we’d become accustomed to such poor air quality,” Hennig said. “There was no haze hanging around the ceiling, and it almost felt like we were working outside. Without the Atherion, my guess is we would have lost at least 15 days of production in 2012.”
In 2013, the company decided to add more CNC machines and expand to a nearby 6,000-square-foot building. They again hired Southport to move the original 15-ton Atherion unit to the smaller building and engineer a new 30-ton unit for the main building.
“If not for the IAQ requirements at Rite Engineering, nearly any packaged unit would have worked,” Nuzzo said. “But, the machine shop needed an ERM to make it economical to provide the air changes necessary for healthy indoor air. The Atherion provides both in a single unit.”
Hospital Boosts IAQ, Saves Energy
For Hardin Medical Center in Savannah, Tennessee, an outdated HVAC system affected its ability to create an optimal environment of care, especially in the critical labor and delivery areas. The aging systems provided inadequate cooling and insufficient humidity control. The medical facility sought to improve the environment of care to increase patient, physician, and staff comfort while also helping to reduce the chance of medical errors and infection. Efficient solutions could also help combat high operational and energy costs.
To get to the root of the issue, hospital administrators completed an environment of care study in partnership with Trane, a brand of Ingersoll Rand, to identify ways to increase patient comfort, physician and staff satisfaction, and the hospital’s bottom line. Based on the results of the studies, Hardin Medical Center leaders identified upgrades that would best meet their needs. The identified energy savings proved significant enough to cover the cost of a new labor-and-delivery-unit HVAC system to provide reliable temperature and humidity control for the labor-and-delivery floor.
A Trane chilled water Performance Climate Changer™ air-handling unit was installed on the low roof outside the labor-and-delivery operating rooms. Designed to improve comfort and aid in patient recovery, the air handler helps the health care facility achieve optimal operating room temperatures and humidity levels, remove airborne contaminants, and decrease sound levels.
Advanced options available with Performance Climate Changer air handlers can address specific air quality needs by managing building humidity better than traditional coil-only cooling systems and by combining high-efficiency MERV-13 filtration with UV-C lights and photo-catalytic oxidation to control a broad range of airborne contaminants including disease-causing bacteria and viruses.
To improve energy efficiency throughout the facility, an HVAC system was added to serve the labor-and-delivery area, and the boiler plant was replaced. The boiler plant consists of two domestic hot water boilers, two condensing boilers, and one noncondensing boiler to provide the needed capacity and redundancy. Two 1,000-gallon hot water storage tanks; a 50-ton nominal heat recovery chiller with chilled, heating, and domestic hot water pumps; a double-wall heat exchanger with a 500-gallon tank for domestic water preheat; hot water heaters; and circulating pumps were also installed. Other retrofits at the hospital include more efficient lighting and low-flow plumbing systems.
The project team also replaced existing pneumatic building controls for the new HVAC system in the labor-and-delivery department as well as the boilers that serve the entire facility with Tracer™ ES, a Web-based systems integration solution that provides an online, enterprise-wide view of all the medical center buildings and systems. Facility managers can access the system from any PC or mobile device on the network to conveniently handle daily operations, such as scheduling, alarm management, and troubleshooting. Hardin Medical Center also uses the controls system to monitor and control energy use, lighting, and HVAC to improve efficiency and maintain optimal temperature, humidity, and carbon dioxide levels.
Administrators at Hardin Medical Center report infrastructure improvements to the facility have reduced annual energy and operational costs by 25 percent while increasing patient comfort and physician and staff satisfaction. In addition, the hospital received an $11,500 rebate from the Tennessee Valley Authority (TVA) for reducing its load on the electrical grid.
“We’re pleased we can provide a more comfortable environment for patients and a more satisfying workplace for physicians and staff,” said Nick Lewis, CEO, Hardin Medical Center. “It’s even better that the improvements generate significant energy and operational savings each year, and that we were able to fund them through a performance contract without any capital outlay.”
Missouri Warehouse Installs HTHV Units
Langendorf Supply Co., a Bridgeton, Missouri-based supplier of HVAC equipment, wanted to reduce operating costs and improve occupant comfort and IAQ in its 42,000-square-foot warehouse area, which houses two forklifts, six loading docks, and several aisles of shelving racks that extend to the facility’s approximately 24-foot-tall ceilings. In collaboration with the DOE (U.S. Department of Energy), Langendorf chose to upgrade its standard gas unit heaters to high-efficiency HTHV (high discharge temperature heating and ventilating), 100 percent outside air units from Cambridge Engineering.
“The new SA-250 HTHV technology is a three-in-one device,” said Randy Niederer, director of marketing, Cambridge Engineering. “You get the most energy-efficient heater available, built-in ventilation from 100 percent outside air, and no need for ceiling fans as the unit is also the air destratification device.”
In a side-by-side comparison in alternating months during the 2013–2014 heating season, the new gas heaters provided:
• Energy savings — The gas heaters consumed 20 percent less natural gas compared to the existing heaters on a normalized basis over the monitoring period. Because the new gas heaters utilize a high-pressure blower to reduce stratification, increased fan electricity consumption offset the thermal savings.
• Thermal comfort — Because the Cambridge Engineering SA-250 HTHV direct-fired gas heater is a high-velocity discharge heater, it was able to reduce temperature stratification and maintained a more uniform and comfortable temperature distribution throughout the facility. The study revealed no more than 5 degrees in temperature difference existed from the ceiling to the floor. Because the shipping and receiving desk is in the rear of the facility, and is part of the open warehouse space, the even temperatures provided by the SA-250 HTHV heaters were a welcome change for the shipping clerk, who is now able to wear a short-sleeve shirt on the job.
• Improved IAQ — The existing unit heaters only recirculated the air within the facility and didn’t bring in any outside air. Because they use forklifts to move stock within the warehouse, and the dock doors are only raised when necessary during cold winter days, Langendorf’s owner was encouraged to hear the Cambridge units used 100 percent outside air to heat the facility. Less contaminated air means better air quality for the warehouse staff.
Ken Arnsmeyer, owner of Langendorf Supply, said the use of fresh air has greatly improved working conditions for warehouse employees.
“They are much more comfortable with this fresh air and even temperatures from ceiling to floor,” Arnsmeyer said. “In the summer, we use the Cambridge units to pull in cool outside air at night and improve the overall comfort during daytime working hours. Best yet, my gas bills have dropped 20 percent, and I’ve even reduced electricity costs by eliminating the destratification fans.”
Publication date: 3/2/2015