The T.G.I. Friday’s in Fort Smith, Ark., is busy — the restaurant hosts about 1,000 customers every weekday and close to 1,800 people per day on the weekends, according to owner Bruce Spinas.
But preparing that much fresh food can lead to hefty utility bills. Between the extensive prep time and the long operating hours, the restaurant is shut down for only four or five hours each day. This means that T.G.I. Friday’s air-conditioning and water-heating systems are constantly running.
While those energy-hogging systems might be a budget buster for many restaurants, Spinas implemented a new integrated air-conditioning and water-heating system from Rheem that turned the energy equation on its head. Whereas a traditional packaged air conditioner takes hot air out of a space and exhausts it through the roof, the H2AC rooftop unit, featuring eSync integration technology, uses that hot air to preheat the restaurant’s potable hot water.
Spinas’ 10-ton H2AC unit provides 114,000 Btus of cooling at 11.2 EER and approximately 150,000 Btus of water heating when the unit is operating in the water-heating mode. When a call for cooling is made and the incoming water is below 95 degrees Fahrenheit, the unit switches to the water-heating mode, thereby transferring the heat extracted by the air-conditioning unit to warm the water while still cooling the kitchen.
With his restaurant using about 1,200 gallons of hot water per day, Spinas’ savings were significant. In the nine months since the system was installed, the restaurant has saved more than $2,600 on its gas bills. T.G.I. Friday’s expects to hit the payback point on the investment in less than two years.
“The Rheem H2AC system has definitely saved energy, and it’s one less thing for me to worry about,” Spinas says.
“By implementing this system with tankless water heaters, restaurants can achieve the lowest possible water heating and cooling costs.”
The H2AC system was designed specifically for restaurants because of their intensive use of both air conditioning and hot water, says Sal Brunetto, corporate national accounts manager for Rheem.
“Restaurants use a lot of hot water and, especially in the kitchen area, there’s a constant need for cooling,” Brunetto says. Those energy uses add up: Water heating and air conditioning constitute about half of a restaurant’s energy use, he says. And restaurants have the highest energy consumption per square foot in the U.S. “They’re relatively small businesses that use a lot of energy.”
Pairing the H2AC rooftop unit with propane or natural-gas tankless water heaters is an ideal combination, Brunetto says. “By implementing this system with tankless water heaters, restaurants can achieve the lowest possible water heating and cooling costs.”
At Spinas’ T.G.I. Friday’s, for instance, he revamped his water heating system with four Rheem Prestige Series condensing tankless water heaters, which operate at 94 percent efficiency, and a 120-gallon storage tank. The H2AC unit preheats the cold water supply from as low as 55 degrees to as high as 138 degrees Fahrenheit. Rheem estimates that the system can save a full-service restaurant approximately 50 percent on its monthly water-heating costs.
The H2AC unit also markedly improves the performance of a tankless water heater. A tankless heater set at 140 degrees Fahrenheit will deliver about three times more hot water per minute when it’s supplied with 115-degree “cold” water than when it’s supplied with 50-degree cold water.
The system’s cost savings really add up when replacing an electrical water-heating system. In fact, just switching from a standard (storage tank) electric water-heating system to high-efficiency tankless water heaters would save a typical full-service restaurant 57 percent, or about $20,000, on their water-heating costs. Converting from a standard tank propane water heater to tankless would save about $3,000.
Brunetto says using the H2AC rooftop unit could add a further $3,000 in savings, depending on the restaurant’s water usage and climate. “It’s very dependent on your run-time hours,” he says. “Someone in Miami is going to have really long cooling run-times, while someone in Minnesota is going to have a very short cooling season.”
The H2AC unit can provide savings with any system that uses hot water, including propane boilers or “combi” units that provide space heating and water heating.
With the sweltering summer months rapidly approaching, now is the right time for restaurants to review their current air-conditioning and water-heating equipment, Brunetto says. “They might have an 8- or 10-year-old rooftop unit, and it’s very low-efficiency or just not operating like it used to,” he explains. “It’s a ticking time bomb from the standpoint of maintenance and service. That unit will fail right when they have their biggest dinner rush.”
To avoid that hassle, owners should identify rooftop units that should be replaced and upgrade to an H2AC unit, Brunetto suggests. Only one H2AC unit is needed to provide water savings for the building; buildings with multiple rooftop units should place the H2AC in locations where it will have the longest run-times, such as over the kitchen.
And owners upgrading to the H2AC unit should strongly consider upgrading to a propane or natural-gas tankless water heater system at the same time, Brunetto says. “You have a plumber or a mechanical contractor already there,” he explains. “We make the conversion process as painless as possible. We provide a tremendous amount of free engineering and project management services. We can help them make the change now so they have the optimum system in terms of efficiency.”