Featuring a unique multi-leg heat transfer system, the new Rheem-Ruud SPIDERfire® line of condensing-type commercial water heaters offers a wide range of BTU inputs, all with ultra-high thermal efficiencies from 92% to 95%. The result is a higher recovery rate – particularly during periods of heavy usage.

With its sleek modern design, the new SPIDERfire is engineered to deliver substantial amounts of hot water to meet the needs of larger commercial applications, such as restaurants, office buildings, schools, retail stores, and the like. The most powerful unit in the series, with an input of 350,000 BTU per hour, can deliver 460 gallons of water per hour at a 100°F rise. Lower-input models – 130,000, 160,000, 199,000, 250,000, and 300,000 BTU/hour - are also available.

Manufactured in Montgomery, all six SPIDERfire units come equipped with a 100-gallon storage tank and can operate on either natural gas or LP. All models can be installed as a single-pipe, power-vented product; or as a two-pipe, power direct-vented product - the latter for environments where negative air pressure or indoor air quality is a concern. All inputs for SPIDERfire are available with ASME certification.

The Rheem-Ruud SPIDERfire has been extensively tested by a third-party agency for water conditions and temperature, corrosive environments, dust and lint, increased cycling and venting configurations, as well as thermal efficiency, according to Chuck Rohde, wholesale market manager. “This is why we are confident in saying the SPIDERfire is the most reliable tank-type water heater available in the fast-growing ultra-high efficiency segment of the commercial market.”

Rheem innovation: The heart of the SPIDERfire is its innovative, patented heat-exchange system: a series of connected, elongated tubes immersed in the water tank and through which heat is transferred to the water by gases from the combustion process. These multiple vertical pipe runs are what give the unit its unique design, as well as its colorful name.

Generated by the burner at the top of the unit, combustion gases are blown down through the large main flue in the center of the unit (see cutaway illustration on this page). They must then traverse nearly the full length of the unit two more times – up another set of tubes and then down again through a third set, as the system works to extract as much heat energy as possible. By the end of this three-phase cycle, the temperature of the flue gases will have dropped to between 110°F and 140°F, or cool enough for condensation to begin. (In contrast, flue gases in a conventional 80%-efficient commercial water heater typically cool to around 420°F to 450°F and therefore remain in a hot, gaseous state.)

This condensing process also has spurred several other Rheem innovations:

Corrosion-protection: The flue condensate is highly acidic and therefore potentially corrosive. To extend the life of the flue system, Rheem coats the tubes with a specially formulated porcelain enamel that resists corrosion.

Easier, less costly venting: The cool temperatures of the flue gases permit venting through standard PVC or CPVC tubing, rather than more expensive, large-diameter, metal B-vent. “With plastic, the contractor can install the product virtually anywhere, using almost any piping configuration he finds workable,” says Ron Johnson, product manager. In addition, when working with the three smallest models in the line, an installer can use two-inch plastic pipe, as well as three-inch or four-inch – further lowering his costs and simplifying his installation.

More durable flue design: The large and complex flue network of the SPIDERfire eliminates “hot spots” - points in the design where hot gases could concentrate, damaging the system over time and even causing premature failure. But the smooth, porcelain-coated contours of the Rheem heat transfer system are engineered to avoid such problems and maintain a more uniform temperature across the entire network. The goal is a more durable product that will better withstand the test of time, even in heavy-commercial applications. 

Energy-efficient “wet-base” design: Rheem engineered a “wet base” approach for the lower portion of its flue system, suspending the first two legs of the flue network in water, rather than connecting them to the bottom of the tank. “Here again, potential hot spots and premature metal fatigue are eliminated,” says Johnson. “In addition, this design also boosts efficiency because heat is not lost through the bottom of the tank, as would be the case with a dry base design.”

Rheem exclusives: Following are a number of additional key features of the new SPIDERfire line, all of them exclusive to Rheem commercial water heaters.

Fast and accurate diagnostics: The Advanced System Sentinel™ Diagnostic System is standard on all SPIDERfire units, enabling installers and service technicians to monitor key functions and components.

A liquid crystal display (LCD), positioned at eye level at the top of each unit, offers easy-to-read status reports on water heater operations. The LCD’s memory includes a scrollable, operational history to detail usage patterns and facilitate troubleshooting.

Multiple water inlets and outlets: Two pairs of hot- and cold-water connections on either side of the water heater jacket provide installation flexibility, especially in difficult retrofit installations.

Thinner profile: Measuring 26.25 inches in diameter – 1.5 to 2 inches smaller than competitive models – the SPIDERfire will fit more easily into tight commercial spaces.

Full-flow, brass drain valve, factory installed, allows for faster draining and servicing.

Direct spark-to-flame ignition system.

Warranty: Standard three-year limited warranty can be upgraded to five years.