Convection vs. Hydronic Electric Baseboard Heaters

Baseboard Heater
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Electric baseboard heaters provide 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 emanating a slow, gentle trickle of heat through the room, both built on the same type of frame, both looking exactly the same on the outside.

 Let's look at common features first:

5 Features Common To Both Convection and Hydronic Heaters

  1. Voltage Options:  Some can run on either a 120 V line or a 240 V line; others only on 120 V but not 240 V.  Tip:  If it's rated for 240 V, it will almost always be able to run on 120 V. The higher voltage heaters don't just put out more heat but are considered to be more efficient than the lower voltage ones.
  2. No Plugs:  Generally, baseboard heaters are meant to be hard-wired directly into an electrical line, rather plugged in. 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.
  3. Slow To Heat Room:  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.
  1. Quiet:  Because these heaters have no moving parts, operation is usually completely silent, except for the "ticking" sound that happens after the thermostat turns off the heater and the electric casing cools down.
  2. No Dust:  These heaters do not blow air--and dust, pollen, and other pollutants--around the room, making them an better option for persons who suffer from allergies or anyone affected by dust.

    Electric Convection:  Cheap, Reliable, Do Not Retain Heat

    This basic type of baseboard heater is often called a convection heater. The functioning "guts" of this heater are comprised of a heating element: electric coils that heat up much like a coils of the inside of a toaster. It has a thermostat located either on the heater itself or, better yet, on the wall.

    • 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: cost. You can purchase a 72", 1,500 watt, 120/240 V heater for as little as $45 to $60 from home improvement stores.
    • Reliable:  Not much can go wrong with convection heaters.  No liquid to leak.  No fan motors to break.  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 this and the following types of heaters.

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

    Instead of electrical heating elements directly heating the air, in hydronic or oil-filled heater systems in the heating element warms the water or oil, which in turn heats the air.

    The water or oil is sealed within the system and do 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:  Hydronics cost more, much more.  A 1,500 watt, 120/240 V heater around 72" will cost 4 times more than the corresponding convection baseboard.
    • Fewer Options:  Convection baseboard heaters offer the greatest overall range of size options.  Fewer of the long (72" and 96") 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.

    Bottom Line

    Hydronic and oil-filled baseboard heaters are considered better than convection heaters solely in terms of energy efficiency.  

    Manufacturers

    1. Cadet:  Cadet is based in Vancouver, Washington and has been in business since 1957. It exclusively makes zonal heating products.  Cadet is the favored brand of Home Depot stores.
    2. Fahrenheat:  Lowe's favored brand is the one with the clever twist of words (Fahrenheit = Fahrenheat).  Fahrenheat is owned by Marley Engineered Products.
    3. Qmark:  This is also a subsidiary of Marley Engineered Products. Qmark is the line of "competitively priced" baseboard heaters, while Fahrenheat is the more upscale line.