On-Demand Hot Water Heaters
and Total home Systems


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Bosch ProTankless Water Heaters    Bosch Water Heating
The Bosch ProTankless line of gas-fired, tankless water heaters offer efficiencies up to 87%. The ProTankless 635ES and 635ESO water heaters supply two hot water outlets simultaneously at a combined rate of 6 gpm. The heaters can also be fueled by either natural gas or propane, and have an electronic ignition, digital temperature control, an energy factor of 0.85, and a 15-year warranty. Model ES contains a sealed-combustion unit for indoor installation that can be vented horizontally or vertically. Model ESO has built-in freeze protection to 5ºF for exterior installation.

Navien Tankless Gas Water Heater    Navien America Inc.
Navien offers ultra-efficient tankless condensing water heaters for commercial and residential applications. Microprocessors and sensors in these units monitor air and gas pressure to maintain the optimal gas-to-air ratio, leading to reduced emissions and improved combustion and energy efficiency—these water heaters have an energy factor of 0.98. Navien uses stainless steel condensing heat exchangers instead of copper, minimizing corrosion and lime build-up and improving performance and durability. The “A” model has a built-in circulation pump and buffer tank and can deliver heated water at flow rates as low as 0.1 gpm (most tankless heaters require a minimum flow of 0.5 gpm). Multiple units can be joined together via the company’s Ready-Link system and controlled by a single remote, so they can be configured for large commercial systems as well as residential use. Warranties provide coverage for 12 years (CR model) or six years (CC model) for heat exchangers, and three years for parts (all models).

Flash and Mobius Tankless Water Heaters    Takagi Industrial Co. USA, Inc.
Takagi's Flash T-H1, T-K2, T-KD20, T-KJr., and T-K3 tankless gas water heaters are suited for residential and commercial applications and have no pilot, so standby losses are negligible. They do use electricity for a power burner and power vent. The Mobius T-M1. T-M32, and T-M50 are commercial units that can link several units together (up to 20 for the T-M1 and T-M32), making them practical for offices, hotels, hospitals, and other large facilities. Takagi’s T-K3 is designed to fit between wall studs, with up to four units interconnected to provide hot water to larger homes. The T-K3 saves water by activating at a flow of 0.5 gpm instead of 0.75 gpm, providing hot water quicker to bathroom faucets and other low-use fixtures. Energy factors range from 0.81 for the T-KJr. to 0.94 for the the T-H1 condensing model.

All in one- Condensing Boiler/Furnace/
On-Demand Hot Water/Heat Recovery Ventilator

Matrix Total Home System    NTI, Inc.
NTI’s Matrix incorporates a gas-fired condensing boiler and furnace, condensing on-demand water heater, and heat recovery ventilator into a single unit, and it is pre-configured for air conditioning. To aid evaluation against stand-alone appliances, NTI used simulations to estimate the efficiency of individual system components for an AFUE of 94 for forced-air and 92.7 for hydronic heating, and an energy factor of 0.85 for water heating. According to NTI, the Matrix's integration and controls provide provide 10%–15% energy savings over high-efficiency units operating separately. The Matrix can deliver five gallons of water per minute at 110ºF (43ºC) without a tank or standby energy loss. Features include efficient, variable-speed, electronically commutated motors (ECM); a microprocessor that adjusts heat output based on the home environment; and a sealed-combustion system that draws in outdoor air and directly vents exhaust. Compared with standard products, the efficient combustion results in less cycling, improved efficiency, and less noise, and it can be vented using conventional plastic piping. The Matrix exceeds Canada’s new P10-07 standard for integrated mechanical systems.

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