Heat pump turns bonus space into media room

Installation of the 12,000 Btu Fujitsu split system is actually quite simple.

The Thomas residence in rural Lancaster County, Pa., sits on a large, nicely landscaped lot near Amish fields and horse meadows. But recently, inside, the family had a comfort problem. When the family built their home six years ago, they were sure that the bonus room above the three-bay garage would be used for storage. But eventually their interest in using most of the space as a media room won the tug-of-war. Dave Yates, president of York, Pa.-based F.W. Behler Inc., was called in for his expert opinion on heating and cooling the room, and recommended a ductless split system heat pump.

The two-story, 3,000-square-foot home has two central HVAC systems; one for the first floor and a separate one for theTMB - The Wholesaler - Features: August 2007: Gateway Supply upper floor. Yates determined that the new media room -- because of its size, the challenge of heating and cooling the space above a non-conditioned garage, and with so much exposure to western wind and sun -- was a larger load than the existing equipment could handle without major changes.

Yates compared the cost of a separate ductless mini-split heat pump system with changes that could be made to the home’s existing comfort systems. Working with the equipment already in place, Yates found that he would need to install a zoned damper system, new ductwork to be routed through restrictive attic spaces, wiring and an extra thermostat.

“Financially, they were almost a coin-toss apart,” said Yates. “But there were many unique advantages to the use of a new mini split.”

A ductless system would avoid ceiling registers and the energy losses that come with holes through the home’s R-45 attic insulation. Ceiling registers hold the potential for cold drafts in winter and also the likelihood, in summer, of ducted hot air blasts following an off cycle. Any alteration of the ducts serving the sleeping quarters would affect air flow, with the possibility of throwing the system out of balance.

Apply the air where and when you want it

Ductless technology is easily zoned because you apply the cooling and heating to interior spaces where and when you want it. This technique saves energy by containing the heat or air conditioning. Other, lesser-used areas of the home aren’t overcooled or heated unnecessarily, as is common with central systems.

Mini splits are ideally suited for home improvement, whether or not an existing central air system is installed. This approach is often less expensive and less disruptive than retrofitting an existing HVAC system. Frequent on-off sequences or “short-cycling” of the central equipment also increases wear and tear, reducing life span. And then there’s the question: Why turn on and run a large central heating/air conditioning unit when there’s really just one room where new comfort conditioning is needed?

Sleek, new mini-splits with variable speed “inverter” technology have been in use for several decades in Eastern and European countries and now they’re catching on in the U.S. as energy costs continue their upward spiral. The notion that every room in a home must be conditioned to the same temperature -- all the time -- is losing its appeal among Americans.

Punch the gas? Or feather it?

“Old school, on-off technology for any type of hvac equipment is rapidly losing its appeal here in the land of plenty,” said Yates. “With this old-style technology, it’s like driving your car with the gas pedal glued to the floor and controlling it purely by turning the ignition key on or off!”

The new approach -- and one that made sense to the Thomas family -- is the use of equipment that continuously modulates its energy production to match heat loss and gain. Sticking with Yates’s car analogy, that’s like feathering the gas pedal in your automobile to meet the speed you need. Toss in new “automatic modulation” and you get ultra-high efficiency operation, complete with the chauffeur to drive the car.

All the homeowner needs to do is to set the desired temperature or humidity level and leave the rest up to the equipment. The “brain” behind it all is a computerized logic module in the outdoor unit that communicates with system sensors and the indoor unit. Together, the indoor and outdoor units are continually monitoring indoor and outdoor temperatures. Sensors feed this information to the logic module. If anything goes wrong, a fault code indicates what’s wrong with the equipment. That way, homeowners can often take care of minor issues without having to call for service. Or, if a technician is needed, they can respond to more detailed fault codes with diagnostic equipment.

Before the Thomases agreed to have the system installed, Yates offered some details about the advantages of these highly efficient inverter mini-splits, including the one-ton (12,000 Btu) Fujitsu split system he proposed for their home:

• There’s no need for electricity-guzzling resistance back-up heating elements. The systems offer superb air filtration and -- because they’re ductless -- there’s no downstream concern about contaminated ducts.
• They’re great at removing airborne humidity. The Thomases’ new unit would offer a dry mode setting for dehumidification without altering room temperatures by more than 1° and operation with low ambient (outdoor temperatures) as low as 0 F. And it would provide precise programmable comfort control using a wireless remote controller.
• Installation is quite simple, with an affordable installation cost.
• No ductwork is required.
• Use of electrical energy would be at its most efficient.

The Thomases were satisfied with Yates’s explanation and agreed to have him install the system. On a muggy summer day in June, Dave, his son Mike, and ace technician Bob Sieger went to work on the install. Three hours later, the job was done and operational.

Stealth conditioning

“The room was noticeably cooler within minutes, and water was streaming steadily through the outside condensate line,” said Yates. “But when the homeowners checked on us toward the end of the job, they couldn’t believe the system was running -- both the indoor fan coil and outside condensing unit operate so quietly that you have to strain to hear them.”

Mr. Thomas was skeptical. “I don’t hear it,” he asked. “How could it be working?” 

To verify that the outdoor unit was running, Thomas had to get on his hands and knees to see the fan blade turning and feel the gentle movement of hot air from the condenser’s coil as heat was transferred from the indoor air handler. He was amazed at the unit’s stealthy operation. Upstairs, Thomas had the same experience. He could feel the comfort; he just couldn’t hear it operating at less than a few feet’s distance. “No noise to interfere with the new surround-sound system,” he said with satisfaction.

“Fujitsu smartly went with significantly more efficient 410a refrigerant and automatic inverter technology,” said Yates. “Other suppliers stuck with R22 refrigerant, which will be phased out in just three years. And now those firms with the more advanced technology are eating their lunch. Rising energy prices and concerns over global warming have pushed consumer attention beyond a focus exclusively on initial cost. ROI’s have increased significantly as energy costs continue to rise. It’s not uncommon to see an ROI of 15% to 25% [comparing difference in cost between old and new technology to the fuel savings that can be achieved], which rivals the best of what’s happening in the stock market. As an added bonus ... the ROI is tax-free!”

Yates explained that 410a systems run at higher pressure, so line sets can be smaller. “And that’s no small savings with current copper prices,” he said. The new refrigerant compound also permits higher operational efficiency, and the compressor can be ramped up to 130% for short periods, transferring more heat into or out of the interior living space.

The 1-ton (12,000 Btu) Fujitsu heat pump has an HSPF of 10.55 in the heating mode, and a 21 seer rating for cooling. “Those ratings are almost off the charts for air-sourced heating and cooling equipment,” said Yates, an HVAC expert with 37 years of experience in the field.

“While the newly established U.S. standard dictates a minimum of 13-seer, those manufacturers that chose to develop inverter technology managed to leave that efficiency rating in the dust,” said Yates. The unit Yates installed for the Thomases offers energy efficiency that’s equal to or higher than many substantially more expensive and site-disruptive geothermal systems.

Typically today, central heat pump systems have hspfs of 5 or 6 and SEER ratings of 13 to 18, and many remain mired in the inefficient, on-off realm with no clue about the actual load required to meet comfort levels. Each rise of 1-seer represents roughly a 10% improvement in energy consumption.

Another facet of this advanced equipment is that inverter technology runs all key components at variable speeds, enhancing efficiency and extending the life of the unit - all at a reasonable cost. Ultimately, the homeowner is rewarded with a whisper-quiet comfort system that gingerly sips electrical current, is better for the environment, and goes in fast. Professionals like it for the same reason. That’s truly a win-win.

For more information, visit www.fujitsu-general.com.