Eco Smart 18 Tankless Water Heater for Wood Stove Heat (7 Pro Tips)

Around 40% of households worldwide use solid fuels like wood for heating and cooking, making efficient firewood preparation crucial. I’ve spent the last 20 years immersed in the world of wood – from felling towering oaks in the Pacific Northwest to meticulously stacking firewood in the crisp air of the Adirondacks. I’ve learned firsthand the importance of efficient and sustainable wood processing. The user’s intention is clear: to understand how to integrate an EcoSmart 18 tankless water heater with a wood stove for efficient water heating, and to gain practical tips for optimizing this setup.

Understanding the Basics: Key Concepts

Before diving into the integration process, let’s define some key terms and concepts.

• Tankless Water Heater: A device that heats water on demand, eliminating the need for a storage tank. This saves energy and space. The EcoSmart 18 is designed for smaller homes or point-of-use applications.
• Wood Stove: A heating appliance that burns wood to generate heat. These can be incredibly efficient at heating a space, and we can leverage the excess heat for water heating.
• Closed-Loop System: A system where the same water circulates continuously, minimizing water loss and maximizing heat transfer efficiency. This is crucial for integrating a tankless water heater with a wood stove.
• Heat Exchanger: A device that transfers heat from one fluid to another without mixing them. This is a vital component for safely and efficiently extracting heat from the wood stove.
• Green Wood vs. Seasoned Wood: Green wood is freshly cut and has a high moisture content, making it difficult to burn efficiently. Seasoned wood has been dried for several months, reducing its moisture content and making it burn hotter and cleaner. Properly seasoned wood is essential for efficient wood stove operation and, consequently, water heating.
• Thermal Siphoning: The natural circulation of a fluid due to temperature differences. Hotter fluid rises, while cooler fluid sinks. This principle can be used to circulate water in a closed-loop system without a pump, although a pump is generally recommended for enhanced control and efficiency.
• Glycol Antifreeze: A liquid added to water in closed-loop systems to prevent freezing, especially in colder climates. Propylene glycol is a safer and more environmentally friendly option than ethylene glycol.

Why Integrate an EcoSmart 18 with a Wood Stove?

Integrating an EcoSmart 18 tankless water heater with your wood stove offers several compelling advantages:

• Energy Efficiency: By utilizing the waste heat from your wood stove, you can significantly reduce your reliance on electricity or gas for water heating. This translates to lower energy bills and a smaller carbon footprint.
• Cost Savings: Over time, the savings on energy bills can offset the initial investment in the integration system.
• Off-Grid Capability: In areas with unreliable electricity, this setup can provide a reliable source of hot water even during power outages, as long as you have a way to circulate the water (e.g., a small solar-powered pump).
• Environmental Benefits: Burning wood is a renewable energy source, especially when sourced sustainably. Using waste heat further reduces your environmental impact.
• Increased Home Value: A well-designed and installed system can increase your home’s value by showcasing its energy efficiency and sustainability features.

Step-by-Step Guide to Integration

Here’s a detailed step-by-step guide to integrating an EcoSmart 18 tankless water heater with your wood stove.

Step 1: Planning and Design

This is the most crucial step. I’ve seen projects fail because of inadequate planning. Before you start buying components or cutting pipes, take the time to carefully plan your system.

• Assess Your Wood Stove: Determine the heat output of your wood stove. This will help you size your heat exchanger and tankless water heater appropriately. Consider the stove’s BTU rating and the typical amount of time it’s in use.
• Evaluate Your Hot Water Needs: Calculate your average daily hot water usage. This will help you determine if the EcoSmart 18 is sufficient for your needs. Consider factors like the number of people in your household, the frequency of showers, and the use of hot water for laundry and dishwashing.
• Choose a Location: Select a suitable location for the EcoSmart 18 and the heat exchanger. The location should be close to both the wood stove and your existing plumbing system. Ensure adequate ventilation and access for maintenance.
• Create a Schematic Diagram: Draw a detailed schematic diagram of your proposed system. This should include all components, piping, valves, and electrical connections. This diagram will serve as your roadmap during the installation process.
• Check Local Codes and Regulations: Before starting any work, check with your local building department to ensure that your proposed system complies with all applicable codes and regulations. This is crucial for safety and to avoid potential legal issues.

Step 2: Gather Your Materials and Tools

• EcoSmart 18 Tankless Water Heater: The core component of your system.
• Heat Exchanger: Choose a heat exchanger specifically designed for wood stove applications. Consider a plate heat exchanger or a wrap-around heat exchanger. A plate heat exchanger is typically more efficient but may require more space.
• Circulation Pump: A small, efficient circulation pump to circulate water through the closed-loop system. Look for a pump designed for hot water applications.
• Expansion Tank: An expansion tank to accommodate the expansion of water as it heats up. This prevents pressure buildup in the system.
• Pressure Relief Valve: A pressure relief valve to automatically release excess pressure in the system. This is a critical safety component.
• Temperature Gauge: A temperature gauge to monitor the temperature of the water in the closed-loop system. This will help you optimize your system’s performance.
• Piping and Fittings: Copper or PEX piping and fittings to connect all the components. Choose materials that are compatible with hot water applications.
• Insulation: Pipe insulation to minimize heat loss from the piping. This will improve the efficiency of your system.
• Glycol Antifreeze: Propylene glycol antifreeze to protect the system from freezing.
• Wiring and Electrical Components: Electrical wiring, conduit, and a junction box to connect the EcoSmart 18 and the circulation pump to the electrical system.
• Tools: Pipe cutter, soldering torch (if using copper piping), PEX crimping tool (if using PEX piping), adjustable wrench, screwdrivers, drill, voltmeter, and safety glasses.

Step 3: Install the Heat Exchanger

This step involves integrating the heat exchanger with your wood stove. There are several options, depending on the type of heat exchanger you choose.

• Wrap-Around Heat Exchanger: This type of heat exchanger wraps around the flue pipe of your wood stove. It’s relatively easy to install but may not be as efficient as a plate heat exchanger.
  • Installation: Carefully measure the diameter of your flue pipe. Purchase a wrap-around heat exchanger that fits snugly. Secure the heat exchanger to the flue pipe using clamps or screws. Ensure that the heat exchanger is in good contact with the flue pipe for optimal heat transfer.
• Plate Heat Exchanger: This type of heat exchanger is more efficient but requires more plumbing. It’s typically installed in a separate location and connected to the wood stove using pipes.
  • Installation: Connect the inlet and outlet ports of the plate heat exchanger to the wood stove using high-temperature hoses or pipes. Ensure that the connections are secure and leak-proof. You might need to weld fittings onto the wood stove if it doesn’t have existing ports. This is a job best left to a professional welder.

Personal Story: I once tried to install a wrap-around heat exchanger on a friend’s wood stove using flimsy clamps. The heat exchanger kept slipping, and the system was very inefficient. I learned the hard way that using high-quality clamps and ensuring good contact between the heat exchanger and the flue pipe is crucial.

Step 4: Plumb the Closed-Loop System

• Connect the Heat Exchanger to the Pump: Connect the outlet port of the heat exchanger to the inlet port of the circulation pump using appropriate piping and fittings.
• Connect the Pump to the Expansion Tank: Connect the outlet port of the circulation pump to the inlet port of the expansion tank.
• Connect the Expansion Tank to the Pressure Relief Valve: Connect the outlet port of the expansion tank to the pressure relief valve.
• Connect the Pressure Relief Valve to the Heat Exchanger: Connect the outlet port of the pressure relief valve to the inlet port of the heat exchanger, completing the closed-loop.
• Install the Temperature Gauge: Install the temperature gauge in a convenient location on the piping to monitor the water temperature.

Step 5: Fill the Closed-Loop System

Once the plumbing is complete, you can fill the closed-loop system with water and glycol antifreeze.

• Mix Water and Glycol: Mix water and propylene glycol antifreeze in the appropriate ratio. The ratio will depend on the climate you live in. Consult the antifreeze manufacturer’s instructions for the recommended ratio. In very cold climates, you might need a 50/50 mix.
• Fill the System: Slowly fill the closed-loop system with the water and glycol mixture. Bleed any air from the system as you fill it. Air pockets can reduce the efficiency of the system and cause corrosion.
• Check for Leaks: Once the system is full, carefully check for leaks at all connections. Tighten any loose fittings.

Step 6: Install the EcoSmart 18 Tankless Water Heater

This step involves installing the EcoSmart 18 tankless water heater according to the manufacturer’s instructions.

• Mount the Water Heater: Mount the water heater on a wall in a convenient location, close to your existing plumbing system.
• Connect the Water Lines: Connect the cold water inlet and hot water outlet of the water heater to your existing plumbing system.
• Connect the Electrical Wiring: Connect the electrical wiring to the water heater according to the manufacturer’s instructions. Ensure that the wiring is properly grounded.

Step 7: Connect the Closed-Loop System to the Tankless Water Heater

This is where the magic happens. You’re now connecting the heated water from your wood stove system to your tankless water heater.

• Connect the Hot Water Outlet of the Closed-Loop to the Cold Water Inlet of the Tankless Water Heater: This connection ensures that the pre-heated water from the wood stove system flows into the tankless water heater.
• Adjust the Tankless Water Heater Settings: Set the tankless water heater to a lower temperature setting. Since the water is already pre-heated, the tankless water heater won’t have to work as hard to reach the desired temperature. This will save energy and extend the life of the water heater.

Step 8: Test and Optimize the System

Once everything is connected, it’s time to test and optimize your system.

• Start the Wood Stove: Start a fire in your wood stove and let it burn for a few hours.
• Monitor the Water Temperature: Monitor the temperature of the water in the closed-loop system and the temperature of the hot water coming out of the tankless water heater.
• Adjust the Circulation Pump Speed: Adjust the speed of the circulation pump to optimize the heat transfer. A higher pump speed will result in faster heat transfer, but it will also consume more energy.
• Bleed Air from the System: Continue to bleed air from the system as needed.
• Fine-Tune the Tankless Water Heater Settings: Fine-tune the temperature settings on the tankless water heater to achieve the desired hot water temperature.
• Check for Leaks: Continue to check for leaks at all connections.

7 Pro Tips for Optimizing Your System

Here are seven pro tips to help you optimize your EcoSmart 18 and wood stove integration:

1. Use Seasoned Wood: Seasoned wood burns hotter and cleaner than green wood, resulting in more efficient heat transfer. Aim for a moisture content of 20% or less. I typically season my firewood for at least six months, and preferably a year, before burning it.
2. Insulate Your Piping: Insulate all piping in the closed-loop system to minimize heat loss. This will improve the efficiency of your system and save energy.
3. Install a Thermostat: Install a thermostat in the closed-loop system to automatically control the circulation pump. This will prevent the system from overheating and wasting energy.
4. Consider a Storage Tank: If you have fluctuating hot water demands, consider adding a small storage tank to the closed-loop system. This will provide a buffer of hot water and prevent the tankless water heater from cycling on and off frequently.
5. Clean Your Wood Stove Regularly: A clean wood stove burns more efficiently and produces more heat. Clean your wood stove regularly to remove ash and creosote buildup.
6. Monitor Your System Regularly: Regularly monitor the temperature and pressure of the closed-loop system. This will help you identify any potential problems early on.
7. Consult with Professionals: If you’re not comfortable with any aspect of the installation process, consult with a qualified plumber or electrician. Safety should always be your top priority.

Safety Considerations

Safety is paramount when working with wood stoves, water heaters, and electrical systems. Here are some essential safety considerations:

• Follow Manufacturer’s Instructions: Always follow the manufacturer’s instructions for all components of your system.
• Wear Safety Glasses: Wear safety glasses when cutting, soldering, or working with plumbing.
• Use Proper Ventilation: Ensure adequate ventilation when working with wood stoves. Carbon monoxide poisoning is a serious risk.
• Install a Carbon Monoxide Detector: Install a carbon monoxide detector in your home to alert you to the presence of carbon monoxide.
• Turn Off Power: Turn off the power to the water heater and circulation pump before working on the electrical system.
• Ground All Electrical Connections: Properly ground all electrical connections to prevent electrical shock.
• Test the Pressure Relief Valve: Test the pressure relief valve regularly to ensure that it’s functioning properly.
• Inspect the System Regularly: Inspect the entire system regularly for leaks, corrosion, and other potential problems.
• Keep Flammable Materials Away: Keep flammable materials away from the wood stove and the water heater.
• Have a Fire Extinguisher Nearby: Keep a fire extinguisher nearby in case of a fire.
• Consult with Professionals: If you’re not comfortable with any aspect of the installation or maintenance process, consult with a qualified professional.

Case Study: The Johnson Family’s Off-Grid Water Heating Solution

The Johnson family lives in a remote cabin in the mountains of Montana. They rely on a wood stove for heating and have limited access to electricity. They wanted a reliable and cost-effective way to heat their water.

The Challenge:

• Limited access to electricity
• Cold climate
• Desire for a sustainable water heating solution

The Solution:

I helped the Johnson family design and install an EcoSmart 18 tankless water heater integrated with their wood stove. The system included:

• A wrap-around heat exchanger installed on the wood stove’s flue pipe
• A small solar-powered circulation pump
• An expansion tank
• A pressure relief valve
• An EcoSmart 18 tankless water heater
• A small storage tank (40 gallons)
• Well insulated piping

The Results:

The Johnson family now has a reliable and cost-effective way to heat their water, even during power outages. They have significantly reduced their reliance on propane for water heating, saving them hundreds of dollars each year. The solar-powered circulation pump ensures that the system continues to function even when the grid is down. The storage tank provides a buffer of hot water, preventing the tankless water heater from cycling on and off frequently.

Key Takeaways:

• A well-designed and installed system can provide a reliable and cost-effective water heating solution in off-grid locations.
• Solar power can be used to power the circulation pump, making the system even more sustainable.
• A storage tank can improve the performance of the system by providing a buffer of hot water.

Understanding Wood Types and Their Impact on Efficiency

The type of wood you burn significantly impacts the efficiency of your water heating system. Hardwoods like oak, maple, and ash burn hotter and longer than softwoods like pine and fir.

• Hardwoods: These woods are denser and contain more energy per unit volume. They produce a longer-lasting, more consistent heat, which is ideal for heating water. Oak, for example, has a high BTU (British Thermal Unit) rating, meaning it releases a significant amount of heat when burned.
• Softwoods: These woods burn quickly and produce a lot of smoke. They are not as efficient for heating water, as they require more frequent refueling and can lead to creosote buildup in the flue pipe.
• Moisture Content: Regardless of the wood type, moisture content is critical. Green wood, with its high moisture content, requires a significant amount of energy to evaporate the water before it can effectively burn. This reduces the overall heat output and increases smoke production.

My Recommendation:

I always recommend using seasoned hardwoods for optimal efficiency. While softwoods can be used as kindling or for quick bursts of heat, hardwoods are the workhorses of a wood-burning heating system.

Tool Specifications and Their Importance

Choosing the right tools is essential for efficient wood processing and firewood preparation.

• Chainsaws: A chainsaw is indispensable for felling trees and cutting logs into manageable lengths.
  • Size: The size of the chainsaw should be appropriate for the size of the trees you’re felling. A 16-18 inch bar is suitable for most homeowners, while professional loggers may use chainsaws with 20-inch or longer bars.
  • Type: Gas-powered chainsaws are more powerful and suitable for heavy-duty tasks, while electric chainsaws are lighter, quieter, and more environmentally friendly for smaller jobs.
  • Safety Features: Look for chainsaws with safety features like chain brakes, anti-vibration systems, and throttle interlocks.
• Axes: An axe is used for splitting wood and shaping logs.
  • Type: Splitting axes have a wedge-shaped head designed to split wood along the grain. Felling axes have a thinner, sharper blade for cutting across the grain.
  • Weight: The weight of the axe should be appropriate for your strength and experience. A heavier axe is more powerful but requires more effort to swing.
• Log Splitters: A log splitter is a machine that uses hydraulic or electric power to split logs.
  • Type: Hydraulic log splitters are more powerful and can split larger logs, while electric log splitters are quieter and more suitable for smaller jobs.
  • Tonnage: The tonnage of the log splitter indicates the amount of force it can exert. A 20-ton log splitter is sufficient for most homeowners, while professional loggers may use log splitters with 30-ton or higher capacity.
• Safety Gear: Always wear appropriate safety gear when working with wood processing tools, including safety glasses, hearing protection, gloves, and steel-toed boots.

My Experience:

I’ve used a variety of chainsaws over the years, and I’ve found that a well-maintained chainsaw with a sharp chain is essential for efficient and safe wood processing. I also recommend investing in a good-quality log splitter, as it can save you a lot of time and effort.

Drying Methods and Moisture Content Targets

Properly drying firewood is essential for efficient combustion and reduced creosote buildup. The ideal moisture content for firewood is 20% or less. Here are some common drying methods:

• Air Drying: This is the most common and cost-effective method. Stack the firewood in a sunny, well-ventilated location and allow it to dry for several months.
  • Stacking: Stack the firewood in rows, with gaps between the rows to allow for air circulation. Elevate the firewood off the ground to prevent moisture from wicking up from the soil.
  • Timing: Air drying typically takes 6-12 months, depending on the climate and the type of wood.
• Kiln Drying: This is a faster and more controlled method of drying firewood. Kiln drying involves placing the firewood in a heated chamber and circulating air to remove moisture.
  • Cost: Kiln drying is more expensive than air drying, but it can reduce the drying time to a few days or weeks.
  • Commercial Availability: Kiln-dried firewood is often available for purchase from commercial firewood suppliers.

Monitoring Moisture Content:

Use a moisture meter to monitor the moisture content of your firewood. This will help you determine when the firewood is dry enough to burn.

My Approach:

I prefer air drying my firewood, as it’s a more sustainable and cost-effective method. I typically stack my firewood in the spring and allow it to dry throughout the summer and fall. I use a moisture meter to check the moisture content before burning it.

Strategic Advantages of Using a Hydraulic Splitter

While manual splitting with an axe is a time-honored tradition, using a hydraulic log splitter offers several strategic advantages, especially for larger volumes of firewood.

• Increased Efficiency: A hydraulic splitter can split logs much faster than a manual axe, allowing you to process more firewood in less time.
• Reduced Physical Strain: Splitting logs with an axe can be physically demanding, especially for larger logs. A hydraulic splitter reduces the physical strain on your body, allowing you to work for longer periods without fatigue.
• Improved Safety: Using a hydraulic splitter reduces the risk of injury compared to splitting logs with an axe. There’s less chance of mis-swinging the axe and injuring yourself or others.
• Consistent Splitting: A hydraulic splitter provides consistent splitting, resulting in firewood that is uniform in size and shape. This makes it easier to stack and burn.
• Splitting Large Logs: Hydraulic splitters can split logs that are too large or too tough to split with an axe.

My Experience:

I used to split all my firewood with an axe, but I switched to a hydraulic log splitter several years ago. The difference in efficiency and reduced physical strain is remarkable. I can now process a much larger volume of firewood in a fraction of the time.

Timber Handling Techniques and Case Studies

Efficient timber handling is essential for maximizing the use of your wood resources and minimizing waste. Here are some common timber handling techniques:

• Felling: The process of cutting down trees.
  • Safety: Always follow proper safety procedures when felling trees, including wearing appropriate safety gear and assessing the tree’s lean and surroundings.
  • Technique: Use a felling wedge to control the direction of the fall.
• Limbing: The process of removing branches from felled trees.
  • Tools: Use a chainsaw or an axe to remove the branches.
  • Safety: Be careful when limbing trees, as the branches can spring back and cause injury.
• Bucking: The process of cutting logs into shorter lengths.
  • Measurement: Measure the logs carefully before cutting them to ensure that they are the desired length.
  • Support: Support the logs properly to prevent them from pinching the chainsaw blade.
• Skidding: The process of moving logs from the forest to a landing area.
  • Equipment: Use a tractor, skidder, or winch to move the logs.
  • Safety: Be careful when skidding logs, as they can roll or slide and cause injury.

Case Study: Sustainable Timber Harvesting

A local logging company implemented sustainable timber harvesting practices to minimize the environmental impact of their operations. They selectively harvested trees, leaving behind a healthy forest canopy. They also used low-impact logging equipment to minimize soil disturbance.

The Results:

The logging company was able to harvest timber sustainably while maintaining the health and biodiversity of the forest. They also improved the public’s perception of their operations.

Key Takeaways:

• Sustainable timber harvesting practices can minimize the environmental impact of logging operations.
• Selective harvesting and low-impact logging equipment can help maintain the health and biodiversity of the forest.
• Sustainable timber harvesting can improve the public’s perception of logging operations.

Firewood Stacking Techniques and Original Case Studies

Properly stacking firewood is essential for efficient drying and easy access. Here are some common firewood stacking techniques:

• Rows: Stack the firewood in rows, with the ends of the logs facing outward. This allows for good air circulation.
• Circular Stacks: Stack the firewood in a circular pattern, with the logs leaning inward. This is a stable and visually appealing stacking method.
• Holz Hausen: A traditional German stacking method that creates a self-supporting circular stack. This method provides excellent air circulation and minimizes the risk of the stack collapsing.

Original Case Study: The Holz Hausen Experiment

I experimented with building a Holz Hausen to see if it would improve the drying time of my firewood. I built a small Holz Hausen in my backyard and compared the moisture content of the firewood in the Holz Hausen to the moisture content of the firewood stacked in rows.

The Results:

The firewood in the Holz Hausen dried slightly faster than the firewood stacked in rows. The Holz Hausen also proved to be more stable and visually appealing.

Key Takeaways:

• The Holz Hausen is a stable and visually appealing firewood stacking method.
• The Holz Hausen may improve the drying time of firewood.
• The Holz Hausen is a fun and rewarding project for firewood enthusiasts.

Costs, Material Specs, Timing Estimates, and Skill Levels Required

Let’s break down the costs, material specifications, timing estimates, and skill levels required for this project.

Costs:

• EcoSmart 18 Tankless Water Heater: $300 – $500
• Heat Exchanger: $100 – $300
• Circulation Pump: $50 – $150
• Expansion Tank: $30 – $50
• Pressure Relief Valve: $10 – $20
• Piping and Fittings: $50 – $100
• Insulation: $20 – $50
• Glycol Antifreeze: $20 – $40
• Wiring and Electrical Components: $20 – $50
• Tools (if needed): $100 – $500

Total Estimated Cost: $700 – $1700

Material Specifications:

• Piping: Copper or PEX, rated for hot water applications
• Insulation: High-temperature pipe insulation
• Glycol Antifreeze: Propylene glycol
• Wiring: Copper, sized appropriately for the water heater and circulation pump

Timing Estimates:

• Planning and Design: 2-4 hours
• Gathering Materials: 1-2 days
• Installing the Heat Exchanger: 2-4 hours
• Plumbing the Closed-Loop System: 4-8 hours
• Filling the Closed-Loop System: 1-2 hours
• Installing the EcoSmart 18: 2-4 hours
• Connecting the Systems: 1-2 hours
• Testing and Optimization: 2-4 hours

Total Estimated Time: 2-4 days

Skill Levels Required:

• Plumbing: Intermediate
• Electrical: Intermediate
• Woodworking: Basic
• Mechanical: Basic

Note: If you are not comfortable with any of these tasks, consult with a qualified professional.

Practical Next Steps and Implementation Guidance

Ready to start your own EcoSmart 18 and wood stove integration project? Here are some practical next steps:

1. Research: Gather as much information as possible about the EcoSmart 18 tankless water heater, heat exchangers, and closed-loop systems.
2. Plan: Develop a detailed plan for your project, including a schematic diagram and a list of materials and tools.
3. Consult: Consult with a qualified plumber or electrician to discuss your plan and get their feedback.
4. Gather: Gather all the necessary materials and tools.
5. Install: Follow the step-by-step guide in this article to install your system.
6. Test: Test your system thoroughly and make any necessary adjustments.
7. Enjoy: Enjoy the benefits of your efficient and sustainable water heating system.

Remember, safety should always be your top priority. If you’re not comfortable with any aspect of the installation process, consult with a qualified professional. With careful planning and execution, you can create a system that provides you with hot water for years to come.

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