Convection vs. Hydronic Electric Baseboard Heaters

Baseboard heater


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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 providing a slow, gentle, and quiet trickle of heat through the room; both built on the same type of long, metal framework; and both looking exactly the same, at least on the outside.

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.

Features Common to Both Convection and Hydronic Heaters

  • 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, it will almost always be able to run on a 120-volt line. The higher voltage heaters not only put out more heat but are considered to be more efficient than the lower voltage ones.
  • No plugs: Generally, baseboard heaters in this class are permanent additions to the home, so they 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.
  • Slow to heat roomBaseboard 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.
  • Quiet: Because these 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.
  • No Dust: 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.

Electric Convection: Cheap, Reliable, Does Not Retain Heat

This is the most basic type of baseboard heater and it is usually called a convection heater. The functioning innards of this heater are comprised of a heating element: electric coils that 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. Locating the thermostat on the wall is an energy-wise decision since that location gives a more accurate reading of the room's temperature.

  • Inexpensive: An electric convection baseboard heater is the cheapest, but also least efficient, type of baseboard heater you can buy. One great advantage of baseboard heaters: low purchase cost.
  • Reliable: 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. Simple devices with no moving parts, convection heaters can last for decades.
  • Heat dissipates quickly: 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.

Hydronic and Oil-Filled: Better Heat, More Expensive, Slower

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.

  • Longer lasting heat: The main value of these systems is that 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. 
  • More expensive to purchase: Hydronic heaters will cost about four times more than the corresponding convection baseboard heater. While the initial outlay is more than with convection heaters, they pay for themselves many times over in terms of energy savings.
  • Fewer options: Convection baseboard heaters offer the greatest overall range of size options. Fewer of the long hydronic heaters are available across all brands.
  • Slower to reach target temperature: One disadvantage of hydronic systems, as compared to the electric coil convection systems, is that they take longer to heat up.
convection vs. hydronic electric baseboard heaters illustration
Illustration: The Spruce / Kelly Miller

Baseboard Heater Manufacturers

  • Cadet: Cadet is based in Vancouver, Washington and has been in business since 1957. It exclusively makes zonal heating products. An exclusive brand of Home Depot stores, 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: A subsidiary of Marley Engineered Products, Qmark is the line of competitively priced baseboard heaters, while Fahrenheat is the more upscale line.