Hydro-Air Heating Systems 101

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Your home’s heating system is one of your biggest energy users in winter, and it has a major impact on your comfort. If you’re in the market for a heating upgrade, it’s well worth considering all the options available before you choose.

Hydro-air systems, while still relatively uncommon, are gaining popularity for their flexibility and reliability. These systems combine two tried-and-true heating methods to give you the best of each.

How Hydro-Air Heating Works

A hydro-air system is part hydronic (water), and part forced air (ducted). Instead of using a flame in the air handler as a conventional furnace does, it heats air with hot water.

The heat for the system comes from a boiler that’s fueled by natural gas, oil or propane. The boiler heats water that’s then pumped through a tube to an air handler similar to the one found in a standard forced-air furnace.

The air handler contains a pump, hot water coil, blower fan and, in most systems, an air conditioning coil. As hot water heats up the heating coil, the blower fan sends cold air from your rooms over the hot coil. The air picks up heat from the coil, and the blower fan moves the air out into the duct system, which distributes it to your rooms.

The same boiler can be used to heat water for household use, such as in your shower and washing machine, so you won’t need a separate water heater. If you want air conditioning, an A/C cooling coil can be installed in the air handler to work in combination with an outdoor condenser unit.

It’s also possible to install a hydro-air system that uses a tankless water heater rather than a boiler, but these are less straightforward in design. Tankless water heaters require a minimum water flow to kick on, and they take time to heat up the water. That means you’ll need an additional storage tank to supply hot water when the tankless system doesn’t.

The Advantages of Heating with Hydro-Air

Hydro-air heating gives you the flexibility to heat every part of your home exactly the way you want with one dependable, space-saving, and energy-efficient system.

Flexibility and Zoning Options

With a hydro-air heating system, you have the option of mixing and matching heat emitters. You might have hydronic radiant flooring in the kitchen and bathroom, hydronic baseboard heaters or radiators in the living room, and forced-air heating throughout the rest of your house. You can even add little luxuries such as hydronic heated towel bars. Alternatively, you can stick with forced air alone.

You’ll also have an easy way to extend hydronic heating to a room addition, finished attic or basement, garage or pool. Extending your heating system this way saves space because you won’t need to run ducts along the ceiling or floors to reach other wings or stories of your house.

Zoning is easier with hydro-air, too. You can use a separate air-handler for each zone and, if you choose, different emitters in different parts of your home to precisely tailor the level and intensity of warmth in every room.

If you use the boiler for household hot water, you’ll free up space that would otherwise be occupied by a hot water heater.

Efficiency and Reliability

Hydro-air systems are as efficient or more efficient than conventional forced-air furnaces. If your home uses an older forced-air furnace and water heater, upgrading to a hydro-air system will let you replace both appliances with a single, high-efficiency system. That could make your upgrade eligible for rebates based on energy efficiency, in addition to cutting your energy bills.

For maximum efficiency, choose a modulating boiler. These boilers vary their energy use based on the amount of hot water you need at the moment.

When you have just one hot water tap on, the system will run at a lower setting. Turn on the shower, dishwasher or heating system, though, and the boiler steps up its output to meet your demand. Heating systems based on these boilers prioritize hot water for the taps and appliances, so you won’t have to worry about getting a cold shower when the heating kicks on.

If you’re interested in eco-friendly heating methods, but you don’t have the space or budget to install a geothermal system, a hydro-air system is a good alternative.

What to Keep in Mind

To run a hydro-air system, you’ll need a gas line large enough to supply your boiler, an electrical supply to power the boiler’s ignition and controls, and space to vent the boiler to the outdoors. For a condensing boiler, you’ll need either a floor drain or a condensate pump.

Installing a hydro-air system is most cost effective if you already have some type of boiler. Otherwise, a new forced air system will cost less than a new boiler plus a hydro-air air handler. If you’re building a new home, however, a hydro-air system with a conventional air conditioning system is likely to end up costing less than radiant flooring combined with a ductless A/C system.

These systems are ideal for small to mid-sized homes with efficient weatherization features such as tight air-sealing and sufficient insulation. In large, drafty homes, however, they can have difficulty providing enough warmth.

Although hydro-air heating systems haven’t gained widespread popularity yet, they’re a practical choice if you live in an energy-efficient home and want a heating system that’s both reliable and highly adaptable.

Posted on Categories HVAC