One of the most remarkable discoveries in nature is that, in the history of the world, no scientist has ever been able to invent a fluid that transfers heat more efficiently than just regular water!

So for example, when a heating fuel is burned, and the heat needs to be distributed throughout one or more buildings, this can be accomplished with a boiler. The advantage of a boiler is that the fuel is burned in just one location and the resulting heat can be transferred to a variety of OTHER locations very easily and efficiently. The fuel burned in a boiler heats water. That water is then circulated through hidden pipes to every section of your home and other buildings to provide comfortable warmth without losing any efficiency. Cool right?!

Water-to-Air Heat Exchanger

As its name sounds, a water-to-air heat exchanger transfers heat from water to air. Many people think these look like a radiator for a car. The hot water passes through small copper tubes that have metal fins attached. The circulating hot water from the boiler heats the tubes and fins. When warmth is needed, a blower fan turns on and blows air through the fins and tubes and voila – warm air!

Water-to-air heat exchangers are most commonly used in forced air ducts. See drawing below. These heat exchangers are often installed in the forced air furnace plenum which is located above the furnace. These come in several sizes, and are often installed by simply attaching “L-Brackets” to the inside of the plenum that the heat exchanger lays on in a “flat” orientation.

Detailed installation instructions are included with every water-to-air heat exchanger purchased at OutdoorBoiler.com.

Water-to-air heat exchangers come in different sizes, some as small as 12”x12” for a small room up to 24”x24” and larger for bigger spaces to be heated.

These heat exchangers transfer heat from one circulating liquid (usually water from the boiler) to a different liquid, WITHOUT mixing the liquids!

These water-to-water plate heat exchangers accomplish this by allowing the hot water (from your boiler) to pass over alternating plates, thus warming them up. The water to be heated is passed through the empty space between those alternating hot plates, which transfers the heat from the boiler water to the other liquid.

For example, to heat your domestic hot water with your outhoor boiler, you will install a “Domestic Hot Water Kit”, which includes a plate heat exchanger so that your outhoor boiler water never mixes with your hot water used in cooking or bathing.

Plate heat exchangers are also used to transfer heat from boiler water to in-floor heating systems, to boiler systems that use baseboard radiant heaters, and to industrial hot water systems such as dairies.

Unit Heaters

The easiest way to heat a workshop or similar spaces is with a “Unit Heater”. This is a self-contained heating system in a small box that includes a water-to-air heat exchanger and a built-in blower fan that turns on and off to keep the room at your desired temperature, according to the setting on your thermostat (thermostat sold separately).