When it came time to replace the tank-type water heater in his Sacramento-area home, Darlington drew on that lengthy experience and chose a Rheem tankless unit.

Darlington opted for installation extras that increased the complexity of the project, thus requiring an extra day and therefore higher labor costs. On average, a standard home conversion from a tank-type water heater to a tankless unit takes one day, perhaps two, and typically costs around $1,200. Because Hank and his wife Carol chose to relocate water lines and recess all the piping behind the walls or underground, their project took three days at a total cost of $6,700.

Work at the Darlington house began with a site visit from lead technician Bill Vanderveer with the Sacramento-based Bonney Plumbing & Rooter Service. Darlington chose the firm for its experience and tankless expertise. “I’ve known Mark Bonney since I owned my own showroom – more than 25 years ago – so I know he’s experienced. Plus, Mark has tankless in his own house, as does Bill.”

The installation took place in the Darlington home’s attached garage, where the 12-year-old, 50-gallon tank-type water heater was located. “Bill made notes and sized the tankless unit to our floor plan and our particular hot-water needs,” Darlington explains.

In addition to proper sizing, “it’s part of our job to determine the best vent for the particular house,” says Vanderveer. “Each home’s layout is different and every family’s water use is unique, so it’s important to consider all the factors before selecting the unit. For venting, you can’t use the existing double-wall B-vent or galvanized vent, per the code. You need a stainless steel direct vent right off the side of the house, or to replace the existing vent through the roof.”

Vanderveer calculated that a Rheem RTG-74 tankless unit was most appropriate for the Darlingtons. Rheem’s largest residential unit, it provides a maximum 7.4 gallons of continuous hot water per minute, making it ideal for this three-bedroom home.

Outdoor installation of tankless water heaters is common in California, but covenants in the Darlingtons’ neighborhood restrict any visible exterior equipment without pre-approval. “I didn’t want to deal with that process,” Hank says. “Besides, all the gas piping was already set up in the neat little corner of the garage, so I decided to keep the unit inside.”

Although the Darlingtons had their new water heater installed in the same spot as the existing unit, they opted to relocate the water line and recess it along with the gas line. Hiding this piping was important to Darlington, who likes to keep his garage neat and well-organized. “I didn’t want pipes and tubing on the walls,” he says, explaining his decision to upgrade from the standard installation.

“Relocating water lines is common, but putting both gas and water lines in the wall and recessing them is not,” notes Vanderveer. “Naturally, completely concealing these lines – including painting, sheet-rocking and the required multiple inspections – adds to the total time of the job and to the cost. I always offer that option, and I show the customer the cost difference. But about 80 percent say no, because concealing the lines can add thousands of dollars.”

Vanderveer increased the size of the gas line from ½-inch to 1-inch, which is typical for a standard tank-to-tankless conversion. “The pipe size is determined by the length or distance from gas meter to the water heater, and we do a schematic of the BTU output,” Vanderveer notes. “A minimum up-sizing is ¾-inch, but it can go as large as two inches. The larger the gas line, the higher the cost. You can save money by putting the heater closer to the meter, which reduces the length of gas line. Better to run the water lines further, since they don’t cost as much to move.”

“Fortunately, our gas line came in only about 10 feet from where we were putting in the Rheem tankless unit,” Darlington says. “Bill cut a pretty good size hole in the sheet rock on the inside of the garage, put the flexible gas tubing through a small hole through the siding of the house, then ran it up the wall, across the ceiling and back down the wall where the new unit was going to be installed.”

To relocate the water line from one wall to another at the back of the garage, Vanderveer cut into the sheet rock around the old heater. “Bill spent a full day prepping the job – running the new gas line, relocating the water lines, getting everything set up so that the sheet-rock guy could come in and close up the holes, and be ready for the county inspector.”

The next step in the installation was to disconnect the gas and water lines and then drain and remove the old tank. “The old water heater had been sitting on a square platform about two-feet high, a result of a Sacramento code requirement to elevate tank-type water heaters in case of an earthquake,” says Darlington. “With our new tankless water heater, the platform was no longer needed. That gave us even more storage space. The Rheem unit is so much smaller – that’s a big plus.”

Again, because Darlington opted to conceal the piping, considerable sheet-rocking and other finish work added a full day to the job. “The walls were all closed up, and the exposed plumbing was ready for us to hang the unit,” he says. “The only things visible on the outside wall are a three-inch galvanized nipple, a shut-off valve, and maybe 12 inches of the new flexible gas line.”

Preparation was key to the smooth installation, and Darlington credits Bonney Plumbing with that. “Because they are so experienced with these installations, they were able to ‘fast-track’ the county-inspection process,” he says. “The inspector put a pressure meter on a gas line, which must maintain pressure over night to show there are no leaks on the line. I don’t think the inspector had seen a lot of tankless installations,” says Darlington, “but Bill answered all his questions, and he signed off on the job.”

Vanderveer says inspections are a crucial part of tankless installation. “It’s a big problem if inspectors don’t know enough about tankless to ensure the right gas line was installed,” he says. “They should be checking the BTU input of the water heater, but a lot of municipalities don’t ask for a schematic, which means there is a risk that the customer will end up with an incorrect size gas line for the meter.”

To be safe, Vanderveer recommends customers ask the plumber how he or she figured out what size pipe to run, and whether they did a load calculation. “When I go to the customer, I explain everything I’m doing,” he says. “My invoices look like a novel. The customer has every right to ask the plumber how he or she figured out what size pipe to run.”

Despite the add-ons, Darlington’s tankless unit was up and running by mid-afternoon on the third day. “My project went extremely smoothly because it was well-executed by the installer,” he says.

“It’s got a nice-looking thermostat, and it’s conveniently located right next to the unit, so you can set the water temperature at whatever level you want,” Darlington adds. “We elected to go with 120°F for ours. Shortly after it was installed, I took a shower – a hot shower! These things are so incredible. With tankless, we will never run out of hot water.”

“It’s true that Rheem’s thermostat lets you set the temperature very accurately – plus or minus two degrees,” Vanderveer says.

“But the thermostat is also a diagnostic tool that will provide an error code, alerting the homeowner to any maintenance problem that may arise. That’s a great product advantage.”

The Darlingtons’ old water heater had a recirculating pump, so Vanderveer connected the new tankless unit to it as well – adding installation costs, but reducing the wait time for heated water. “Within three to five seconds, Hank and Carol have hot water at the tap,” Vanderveer says, “but the wait time always depends on the system and the floor plan. In my house, for example, the tankless unit is installed over our clothes washer. For the fixture furthest away, it takes 30 to 60 seconds.”

In addition to the convenience of continuous hot water, Darlington also expects to benefit from tankless technology’s energy efficiency. “A tank heater is cooking all the time,” he says, “while a tankless unit uses gas only when somebody turns on the hot water. It’s a green product, and I am proud to help make the world greener.”

Space-savings turned out to be a big benefit for the Darlingtons as well. “As soon as I was done sweeping the floor I turned around, and Hank was already putting his golf clubs in the empty space where the old tank had been,” Vanderveer said.

“The bottom line is that the initial cost is more for tankless,” Darlington says. “But the plusses include saving natural gas and not having to replace a tank-type unit in eight to 10 years. This tankless unit should last a minimum of 15 years. We used to run out of hot water. I’m confident that will not happen again, and I think we’ll save money on gas.”

About Rheem Manufacturing Company
Rheem Manufacturing Company (www.rheem.com) is a privately held company with headquarters in Atlanta, Ga. In its 81st year of operation, the company manufactures a full-line of high-quality residential and commercial heating and cooling systems, water heaters, swimming pool heaters and commercial boilers throughout North America and world markets. The premium brands of Rheem Manufacturing Company include Ruud, Raypak and Rheem. Rheem Manufacturing Company is the major associate sponsor of Richard Childress Racing and the No. 29 team driven by Kevin Harvick, 2007 Daytona 500 Champion, 2007 Craftsman Truck Series Champion and 2006 Busch Series Champion. Rheem is also the primary sponsor of Kevin Harvick Inc.’s No. 33 and No. 77 car for four high-profile Nationwide Series races in 2008.