Convection vs. Hydronic Electric Baseboard Heater

Electric baseboard heaters provide an economical secondary heat source for primary HVAC systems. Or they can act as the primary heat for peripheral spaces like cabins, basements, or additions. Rarely are they used as the only heat source, except in some warmer climates where additional heat is rarely needed.

There are two different types of baseboard heaters: convection and hydronic. They have many similarities: Both provide a slow, gentle, and quiet trickle of heat through the room; both are built on the same type of long, metal framework; and both look exactly the same, at least on the outside.

Baseboard heaters do not blow air, dust, pollen, pet hair, dander, and other pollutants. This makes them a better option for persons who suffer from allergies or anyone affected by dust.

Convection vs. Hydronic Electric Baseboard Heater: Major Differences

Convection baseboard heaters do not stay warm for very long after the thermostat kicks off. The inside heating elements and the outer steel case quickly cool down, and this is the critical difference between convection and hydronic or oil-filled baseboard heaters.

Key Features

Convection Heater

A convection heater is the most basic type of baseboard heater. The functioning innards of this heater are comprised of a heating element. The interior electric coils heat up much like coils inside a toaster. This type of heater either has a thermostat located on the heater itself or on the wall.

Hydronic Heater

Instead of electrical heating elements directly heating the air, with hydronic or oil-filled heater systems, the heating element warms the water or oil, which in turn heats the air. The water or oil is sealed within the system and does not require recharging.

Sizes

Convection Heater

Convection baseboard heaters offer the greatest overall range of size options across all brands. Sizes can range from a short 20-inch length to a longer 96-inch length and everything in between.

Hydronic Heater

You'll have fewer options from which to choose across all brands if you opt for long hydronic heaters. Common lengths range from 35 inches to 94 inches and limited lengths in between.

Best for Sizes: Convection Heater

If you have various lengths you need to fill with baseboard heaters, you'll find more lengths from which to choose across all brands of convection heaters. Many convection heaters are sold in popular lengths measured by the foot.

Repair and Maintenance

Convection Heater

Not much can go wrong with convection heaters since there is no liquid to leak, no fan motor to burn out, and no ducts to clean. If there is a problem, you may be able to fix it yourself.

Hydronic Heater

Electric hydronic baseboard heaters seldom fail and need little to no maintenance. If you have a boiler-style heater, to keep it working efficiently, you will need to make certain your furnace or boiler is working at its best. That means watching out for corrosion, rust, or calcium deposits. Typically, you will need to call in a certified service person who is qualified to specially handle hydronic heating systems.

Best for Repair and Maintenance: Convection Heater

It is easier to repair and maintain a convection heater, especially if you want to tackle it yourself. You may hear some minor noises coming from the convection heater, but that is most likely just the heating element expanding and contracting, which is completely normal.

Noise

Because both types of heaters have no moving parts, their operation is usually completely silent, except for the "ticking" sound that happens after the thermostat turns off the heater and the electric casing expands and contracts for both types of heaters.

Energy Use

Convection Heater

A convection heater uses about the same amount of energy as a hydronic heater. However, a convection heater may not stay hot as long as a hydronic heater which could translate into using more energy to keep the room's temperature constant and comfortable.

Locating the thermostat on the wall is an energy-wise decision since that location gives a more accurate reading of the room's temperature.

Hydronic Heater

One disadvantage of hydronic systems, as compared to the electric coil convection systems, is that they take longer to heat up and reach a target temperature. However, the main value of these systems is that they have longer-lasting heat.

The liquid will remain warm for much longer after the thermostat goes off. You can think of these as being like steam or water radiators. In hydronic systems, they might be self-contained or they might be fed from a central boiler system. In the self-contained types (which most homeowners will purchase), the baseboard heaters are located intermittently throughout the room, as needed. 

Best for Energy Use: Hydronic

While the initial cost outlay of hydronic heaters is more than with convection heaters, they pay for themselves many times over in terms of energy savings. Baseboard heaters' economical nature stops after you leave the cash register. Inexpensive to purchase and equally inexpensive to install (when you do it yourself), baseboard heaters are notorious energy-wasters. One way to curb their appetite for electricity is to purchase a hydronic heater rather than a convection heater.

Both types of baseboard heaters can heat up quickly, but it takes a long time for the space itself to warm up since this is radiant, not fan-driven, heat. Heat time varies, but usually, you can expect to wait 30 minutes or even up to an hour for the room to feel comfortable. But it's this slow trickle of heat that homeowners prize, rather than the quick blast of hot air that you might get from HVAC forced-air heating. The higher voltage heaters not only put out more heat but are considered to be more efficient than the lower voltage ones.

Installation

Generally, baseboard heaters in this class are permanent additions to the home, so both types are hard-wired directly into an electrical line, not plugged into an outlet. For that reason, homeowners who are not confident about dealing with electrical work choose to have these products installed by electricians. Some plug-in models can be found, though.

Both types of heaters have voltage options. Some baseboard heaters run on either a 120- or 240-volt line. Other heaters only run on a 120-volt line but not a 240-volt line. If it is rated for 240 volts, most often it will only work properly if connected to a 240-volt circuit.

Cost

Convection Heater

An electric convection baseboard heater is the cheapest, but also least efficient, type of baseboard heater you can buy.

Hydronic Heater

Hydronic heaters will cost about four times more than the corresponding convection baseboard heater.

Lifespan

Convection Heater

Simple devices with no moving parts, convection heaters can last for decades.

Hydronic Heater

With yearly maintenance to prevent corrosion, a hydronic heating system will last between 10 and 20 years, or quite possibly longer.

Best for Lifespan: Convection Heater

Though you may pay a bit more for the energy a convection heater uses, it may last a bit longer and with fewer worries than a hydronic heater.

The Verdict

Hydronic heaters create even and consistent heat, but at a price. For less maintenance and ease of mind, convection heaters may be a better bet for most households.

Top Brands

Cadet is based in Vancouver, Washington, and has been in business since 1957. Cadet provides ample assistance on its website for do-it-yourselfers who wish to install their own heaters.

Fahrenheat, Lowe's favored brand is the one with the clever twist of words. Fahrenheat is owned by Marley Engineered Products. Fahrenheat baseboard heaters are comparable to Cadet in terms of sizing, features, and cost.

Qmark, also a subsidiary of Marley Engineered Products, is the line of competitively priced baseboard heaters, while Fahrenheat is the more upscale line.