Looking for a dependable way to heat your home or workshop with your outdoor wood boiler or hydronic system? A water-to-air heat exchanger might be exactly what you need.

This device transfers heat from hot water into the air using finned copper coils and a blower fan, turning heated water from your system into warm air that circulates throughout your home or shop. It’s a highly efficient way to integrate hydronic heating with forced air, giving you the warmth you want without the high energy costs.

Built for Performance Across Applications

A water-to-air heat exchanger is a reliable solution across a wide range of heating setups. Whether you're running heat from a wood boiler, a pressurized tank, or even a solar thermal system, these units get the job done.

They’re especially useful for those wanting to maintain independence from grid-based heating, like many of our customers who live off-grid, in rural areas, or who just prefer the long-term savings and control of heating with wood.

You’ll get:

• Consistent performance in both residential and light commercial settings
• Quick warm-up times with properly sized units
• Flexible installation options to match your ductwork and HVAC layout

Heat Exchanger Features

Our water-to-air heat exchangers are designed with reliability, durability, and ease of installation in mind:

• High-Efficiency Heat Transfer – Finned copper coils increase surface area for faster and more even heat distribution.
• Compact Design – Fits easily into your existing ductwork or plenum box. No major HVAC overhaul needed.
• Durable Materials – Built with copper and aluminum, these materials hold up against corrosion and daily wear.
• Easy Installation – Includes pre-mounted brackets and standard 1” connections to get you up and running quickly.
• Versatile Compatibility – Whether you're using a hot water heater, outdoor wood boiler, or even a liquid-to-air heat exchanger setup, these exchangers work with open-loop or pressurized systems.

For spaces that need rapid heating or better airflow, consider our water-to-air heat exchanger with fans, like the Dragon Breath heater series. These units combine the efficiency of copper coils with a powerful fan to push warm air where it’s needed most.

Common Use Cases

We hear from folks all over who use hot water heat exchangers in a variety of situations. Here are some common ones we see every week:

• Tying outdoor wood boilers to existing duct systems for whole-home heating
• Warming up detached buildings like garages, barns, or greenhouses
• Retrofitting old systems with more efficient modern components
• Supplementing solar thermal systems when the sun just isn't cutting it

And yes, they’re perfect for off-grid homes. If you’re trying to save money, stay self-reliant, and avoid propane or electric bills, this is a smart way to do it.

Why Trust Alt Heat Supply

We know how frustrating it is to deal with overpriced parts, limited sizes, and slow shipping, especially when your heat is on the line.

That’s why we do things differently:

• Wide range of sizes & BTU outputs – So you’ll find exactly what your setup needs
• Premium materials – Nothing cheap or flimsy; we prioritize durability
• Fast shipping – We get your order out quickly so you're not left in the cold
• Top-tier customer support – Got questions? We’re real people who know these systems

You’ll find everything you need in one place, from pumps to pipes to our full line of heating & plumbing parts.

FAQs

How efficient is a water to air heat exchanger?

Very efficient. Finned copper coils maximize heat transfer, letting you get more warmth from less water, ideal for wood boilers and off-grid systems.

How does a water to air heat exchanger work?

Hot water flows through copper tubes inside the exchanger. A blower fan pushes air over the heated fins, warming it up and distributing it through your ducts.

What size water to air heat exchanger do I need?

It depends on your square footage, BTU output, and water temperature. If you're not sure, give us a call, we’ll walk you through the sizing. A popular mid-range option is the 18"x18" size, good for around 100,000 BTUs.

Can I use a water to air heat exchanger with an outdoor wood boiler?

Absolutely. In fact, many of our customers are replacing old or broken exchangers from outdoor boilers. Our units are built to handle open-loop and pressurized setups.

Let's Get You Set Up

You can spend more elsewhere—but why would you, when you can get better value and better service from Alternative Heating Supplies? Shop our full lineup of heat exchangers for HVAC and wood boilers today. Questions? We’re happy to help.