Outdoor Tankless Water Heaters

Outdoor tankless water heaters are available in natural gas and propane configurations with flow rates ranging from 5.0 to 11+ GPM depending on the model and manufacturer. Most outdoor units include weather-resistant housings, freeze protection systems, and corrosion-resistant components rated for year-round exterior exposure. Brands carried by The Trade Table include Rinnai, Eccotemp, and Noritz.

The Trade Table carries outdoor tankless water heaters in natural gas and propane configurations from Rinnai, Eccotemp, Noritz, and other leading manufacturers for whole-home, off-grid, and commercial hot water applications.

Outdoor Tankless Water Heaters | Exterior Gas & Propane On-Demand Units

An outdoor tankless water heater mounts on an exterior wall and connects to the home's water supply and gas line through the wall. When a hot water tap is opened inside the home, cold water flows through the unit, passes over a gas-fired heat exchanger, and returns inside the home at the set temperature. Because the unit is outside, all combustion exhaust vents directly into the atmosphere with no ductwork required.

This exterior installation eliminates the most complex and expensive part of indoor tankless installation — venting. Indoor tankless units require stainless steel or PVC vent runs through walls or roofs, which adds material cost, labor time, and installation constraints. Outdoor models bypass this entirely, making them the simpler and often less expensive installation option.

Outdoor units are built with weather-resistant enclosures and freeze protection technology to operate in cold climates. Most models include electric freeze protection heaters that activate automatically when temperatures drop near freezing. In extreme cold climates, additional precautions such as recirculation lines or insulated pipe covers may be recommended.

Outdoor Tankless Water Heater Options

• Natural gas outdoor tankless water heaters for whole-home hot water
• Propane outdoor tankless water heaters for homes without natural gas service
• Condensing models with high-efficiency heat recovery
• Non-condensing models for straightforward exterior installations
• Flow rates from 5.0 to 11+ GPM for single-bathroom to multi-fixture demand
• Built-in freeze protection for cold climate exterior mounting
• Wi-Fi enabled models with smart recirculation and temperature control
• Residential and light commercial output capacities

Benefits of Outdoor Tankless Water Heaters

• No indoor venting, flue pipe, or combustion air supply required
• Simpler and often less expensive installation than indoor tankless models
• Frees up interior wall and utility closet space
• Weather-resistant housings rated for year-round exterior exposure
• Built-in freeze protection for operation in cold climates
• Continuous on-demand hot water that never runs out
• Higher efficiency than traditional tank water heaters with no standby energy loss

Common Uses for Outdoor Tankless Water Heaters

• Whole-home hot water supply mounted on an exterior wall
• Replacing an aging indoor tank water heater without adding indoor venting
• New construction where exterior mounting simplifies gas and water routing
• Homes with limited interior utility closet or mechanical room space
• Retrofitting from tank to tankless where indoor venting is impractical
• Vacation homes, cabins, and secondary structures with exterior wall access
• Pool houses and detached buildings needing dedicated hot water

Why Buy Outdoor Tankless Water Heaters from The Trade Table?

The Trade Table helps customers select the right outdoor tankless water heater based on household size, GPM demand, fuel type, and climate conditions. Our team provides guidance on choosing between natural gas and propane models, condensing versus non-condensing configurations, and sizing the unit to peak hot water demand. We carry outdoor tankless water heaters from Rinnai, Eccotemp, Noritz, and other leading brands.

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Outdoor Tankless Water Heater FAQs

Why install a tankless water heater outdoors instead of indoors?

The primary advantage is eliminating indoor venting. Indoor tankless units require stainless steel or PVC vent pipes routed through walls or roofs, adding cost and complexity. Outdoor models vent combustion exhaust directly into the open air, removing the venting requirement entirely. Outdoor installation also frees up interior utility closet or mechanical room space.

Do outdoor tankless water heaters work in cold weather?

Yes. Most outdoor tankless water heaters include built-in electric freeze protection that activates automatically when temperatures approach freezing. This prevents water inside the unit from freezing and damaging the heat exchanger. In extreme cold climates, additional measures such as insulated pipe covers or recirculation lines may be recommended to protect exposed water pipes between the unit and the wall penetration.

What size outdoor tankless water heater do I need?

Sizing is based on GPM flow rate and temperature rise. Add the GPM of all hot water fixtures that may run simultaneously — a typical shower uses 2.0 to 2.5 GPM, a kitchen faucet uses 1.5 GPM, and a dishwasher uses 1.0 to 1.5 GPM. Select a unit that meets or exceeds the total GPM at your region's required temperature rise. Warmer climates require less temperature rise and get higher effective GPM from the same unit.

Can an outdoor tankless water heater replace a tank water heater?

Yes. An outdoor tankless unit connects to the same water supply and hot water distribution pipes as a tank water heater. The gas line may need to be extended to the exterior mounting location. Because no indoor venting is required, outdoor tankless models are often the easiest retrofit path when converting from a tank to a tankless system.

Do outdoor tankless water heaters need electricity?

Yes. Outdoor gas tankless water heaters require an electrical connection for the electronic ignition, control board, and freeze protection system. A standard 120V outlet near the exterior mounting location is sufficient for most residential models. If power is lost, the unit will not operate until electrical service is restored.