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7 comments
Participant

Join Date: Feb 2007
Posts: 2

Baseboard vs oil filled radiant heat

02/20/2007 10:53 AM

Greetings from the land North of THE boarder;

I spent a few hours reading through your forum & am delighted with your proffessional interaction ~ at I gleaned that one gains more respect by registering & loging in to post.

In this light please do not assume that I have knowledge on the subject ~ rather that is what I am seeking.

Currently we have electric baseboard heat in some of our buildings & I was wondering if it would be more economical to install oil filled radiant heat instead. Upon reading through one of your forums ~ it did not seem to be more economical.

Which brings a question to mind ~ if there is no difference in electric radiant heat then would an incandescent light bulb give us light as well as heat? Or for that matter any electric appliance?

Thank you in advance,

John for Hortico ~ growing plants to offset the need for fossil fuel.

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Guru
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#1

Re: Baseboard vs oil filled radiant heat

02/20/2007 3:54 PM

Someone can correct me if I am wrong, but I don't think you will gain efficiency from an oil filled electric heater vs any other electric heater. The conversion of electricity to heat is the same no matter what type of element you use. Heater elements don't waste electricity in there conversion. The only real difference in electric heaters is distribution, safety and how dry they make the air. I am not sure but I think the advantage of an oil filled heater is that it is safer and doesn't dry out the air as much.

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Join Date: Dec 2006
Location: Buffalo, New York
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#6
In reply to #1

Re: Baseboard vs oil filled radiant heat

02/21/2007 10:39 AM

I think also the oil filled heater is cooler to touch vs. electric heater.

MidniteFighter

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Guru
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#7
In reply to #1

Re: Baseboard vs oil filled radiant heat

02/21/2007 7:59 PM

Frank,

You are absolutely right about electric heaters, except that none of them can dry out the air (where would the moisture go?). The process of heating the air, by any means lowers the relative humidity, which makes it "dryer". The common misconception about some heaters drying the air more than others has its origins in the case of bare element electric heaters, where the exposed red-hot elements singe dust particles in the air as it passes over them, and these singed particles are a respiratory irritant of sorts which makes the air seem dryer than it actually is.

Oil filled heaters are safer than heaters with "exposed" parts that are hot enough to ignite materials, or burn someone but other than that they are not. Many electric baseboard units distribute the heat well without the benefit of oil, by merely having a low enough wattage per unit length that the element doesn't get too hot that it would pose any hazard, or singe the dust particles. Then of course you have the oil filled or antifreeze filled baseboard units too besides the free standing ones.

Regards, Greg

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Guru

Join Date: Aug 2006
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#2

Re: Baseboard vs oil filled radiant heat

02/20/2007 5:58 PM

The incandescent light bulb is very similar to (but a tiny bit different than) other heating elements. Incandescent bulbs are about 5-10% efficient in creating visible light (with the rest going off as heat). So if it is cold out, then you might just as well use incandescent bulbs (instead of compact fluorescents) in an electrically-heated home. (In a gas-heated home, gas heat is so much more efficient than electrical heat -- only about 30% of the fuel's energy at the powerplant reaches your house -- that compact fluorescents are the way to go all the time). (And of course, in practical terms compact fluorescents are the way to go in any home.)

In any case, an incandescent bulb is a pretty efficient heater and an inefficient illuminator. But if your house has windows, then some of the energy from a light bulb goes out the window, in the form of visible light. The IR light gets reflected by the windows and remains in the room (heating it). The UV light gets absorbed by the window glass, warming the glass, which re radiates the heat both inward (more heat)and outward (lost).

So, is a light bulb as effective as other heaters (any of which can be considered 100% efficient: fan, no fan, oil, no oil, ceramic, tungsten wire...)? Not quite. But given that only about 7% of a light bulb's energy output is in the form of light, and given that most of the light is absorbed by things in the room, probably only 2%-3% of the total energy leaves through the windows -- maybe even less.

Boaters will sometimes leave a 100 watt bulb burning (sometimes protected from impact by a coffee can) inside the boat to heat it slightly to reduce the relative humidity enough to ward off mold.

Other appliances: your $9.95 toaster is precisely as efficient as a $150.00 space heater. (Granted the distribution of heat might not be to your liking -- so a fan would help -- and it, too, would add to the heat.) Interestingly enough, a 100 watt fan, running in a room with the doors closed, will also heat the room as well as a 100 light bulb.

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Power-User

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#3

Re: Baseboard vs oil filled radiant heat

02/20/2007 11:23 PM

The above posts are correct for the most part. However, if the oil filled heater is truly more "radiant" then there may be some advantage. Using the lightbulb as an example, if a heater is at a certain temperature, more of the energy is released as IR. In the end, this would not be more effective in terms of room temperature, but may make peaople feel warmer, because the IR is converted to heat on their clothes and body, rather than just heating the air. However, the ability to radiate occurs more at high temperatures, not at the lower temperatures seen with oil filled heaters. So, other than safety, I doubt that the oil filled heaters (which typically operate by convection) would have an advantage.

Heaters (of any type) do not effect humidity levels, so one type is not any more drying than another. As the temperature goes up, the relative humidity goes down, by definition, but it is the same for all heaters.

Tad

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#4

Re: Baseboard vs oil filled radiant heat

02/21/2007 6:21 AM

Hi plantseven

First of all welcome to CR4, I hope you find is as rewarding as I do.

Currently we have electric baseboard heat in some of our buildings & I was wondering if it would be more economical to install oil filled radiant heat instead. Upon reading through one of your forums ~ it did not seem to be more economical.

As everybody else has said electrical heaters are 100% efficient at converting electricity into heat but in your situation the oil filled heaters may be a better bet for a couple of reasons.

The main reason is that they are normally positioned so they only heat the air in the room where as the baseboard heaters may be heating a fair amount of wall and surrounding material. Ultimately this all ends up in the room but it will mean you are heating slightly more mass and slow the process down somewhat.

Another thing that is often used to make existing heating more effective is the installation of ceiling fans. Most people believe that ceiling fans are only use to keep you cool in hot weather but good ones are reversible. The way they can be used when heating is to circulate the hot air that collects near the ceiling back into the room giving you a more even heating. This will save you money by shortening the time that it takes to warm a room and by getting rid of the hot air at the top of the room it will reduce the amount of heat lost through the ceiling.

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Participant

Join Date: Feb 2007
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#5
In reply to #4

Re: Baseboard vs oil filled radiant heat

02/21/2007 8:19 AM

Greetings to all,

As before I am only to gain by reading your insights ~ thank you indeed. We have decided to leave the existing baseboards & focus on heat loss by reflective insulation & perhaps ceiling fans. And for new installation where electric heat is the only option we will invest in oil filled radiant heaters.

Until then we are looking at sources for low cost electricity. We are considering wind generators & solar panels ~ we use a tremendous amount of electricity as we need heat in the winter & refridgeration in the summer for our cold storage warehouses.

Once again thank you for your excellent response!

John for all of us here @ Hortico.

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Users who posted comments:

Blink (1); frankd20 (1); Greg G (1); masu (1); MidniteFighter (1); plantseven (1); Tad (1)

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