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How Does an Indirect Water Heater Work?

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For homeowners looking for the most energy-efficient, low-cost water heater currently on the market, an indirect water heater is the best option.  Also known as a tankless coil water heater, an indirect water heater makes use of your home’s space heating system to heat water. When paired with a specifically designed high-efficiency boiler or furnace, this type of water heater far more effective than any other. Whether you need to replace a broken water heater, or whether you just want to upgrade to a higher-performing, more energy-efficient model, an indirect water heater is something to put at the top of your shopping list.

How It Works

An indirect water heater uses a storage tank, combined with the heat from your furnace or boiler, to provide you with all the hot water you need. A heat exchanger attached to your water heating unit is heated by the main boiler or furnace. The water heater then moves the water into a storage tank, similar to a standard water heater, where the hot water is kept until you need it.

How It Saves You Money

When compared to other hot water heater models, an indirect water heater helps you save money. Since it uses your space heater to heat water and air, an indirect model water heater saves you money during cooler months when your furnace runs regularly anyway. Indirect water heaters can also save you money on water-heating bills during the summer, especially for units that operate from solar power. For the ultimate in cost-saving measures, use a combination of a solar water heater with a highly efficient boiler or furnace. This will allow you to enjoy the energy-efficiency that comes from solar power as well as the constant hot water from a reliable heat source.


While it is possible to install an indirect water heater yourself, it is probably a better idea to have a licensed plumber tackle this project. Since installation requires extensive experience in plumbing, HVAC, and electrical work, this is work best left to the expertise of a professional. This will ensure your new energy-efficient water heater performs optimally, saving you money in the long-run.

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