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# heatloss calculation for a room

## heatloss calculation for a room

#1
07-21-05, 01:13 AM
Eddiebx
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heatloss calculation for a room

I am trying replace my old radiator in my bathroom with a new baseboard hot water radiator. It seems to be on old style copper finned element, with a big enclosure around it, which I think is to keep the heat in it or what not, which reduces heatloss?

I searched and found a rough formula of: width x length x 45, given a 8ft height.

My room is 6ft by 13ft and 8ft high. so I end up with 3510 btu/hr.

From the heatloss calculator website I found, I get the following results:

Total Heat Loss for 60O F Temp. Diff. = 2,955.68
Total Heat Loss for 70O F Temp. Diff. = 3,487.70
Total Heat Loss for 80O F Temp. Diff. = 3,960.61

which leads me to believe the formula is pretty close.

only thing I am unsure if is, if this is the correct way I am using the formula? because in the heatloss calculator it talks about measure the entire house dimensions, so I am unsure if i can apply it to a single room.

And lastly, when sizing the correct baseboard length, would it be better to under shoot the btu/hr or over shoot it a bit? basically have more btu/hr than I need or less than I need according to the calculator. or try to be dead on?

Thanks alot for your help!

Eddie

#2
07-21-05, 02:13 PM
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Location: Delaware, The First State
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What you have in there is called a convector. If you can give me the physical size (length, depth, & height) I can probably tell you the btu output of it. If I was going to install baseboard in place of the convector, I would probably add a little. Convectors, for the amount of floor space they take up give off a lot of heat. Personally I would not replace it unless I had to. The enclosure creates a chimney effect & increases heat transfer. BTW, they still make convectors.

#3
07-21-05, 02:26 PM
Eddiebx
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ah, i was browsing through home depot and lowes, and only saw baseboard style radiators so I thought the old style was discontinued.

basically the element inside is all beat up, fins are damaged, plus the casing is old and disgusting looking, so i was looking to replace it because I am remodeling the rest of the bathroom.

if i wasnt concerned with the floor space, would the two units produce equivalent heating? at the same efficiency, or is one more efficient than the other. meaning the old convector which is 2ft long, vs say a new 5ft long baseboard.

the dimensions of the convector are 24" x 24" x 6"

given my situation would you recommend I source out a new convector unit to replace it with, or would the baseboard be sufficient?

thanks alot!

#4
07-21-05, 07:37 PM
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Convector vs. baseboard

According to my reference materials, you would need about 6 feet of baseboard to yield the same amount of heat as you would get from a 24x24x6 convector. If you only have 5 feet of space, I doubt seriously if you would notice the difference. By staying with a convector there would ceratainly be less piping issues to deal with.

#5
07-21-05, 07:39 PM
Eddiebx
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ah, i have plenty of room along the wall, theres a good 7-8ft of free wall space i can put a baseboard unit on.

so basically convector = space saving?

#6
07-21-05, 07:47 PM
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Convectors

Yes, they save a good bit of floor space. Baseboard in a bathroom does tend to rust a lot faster than it does in the rest of the house because of all the moisture in the bath.

#7
07-21-05, 08:18 PM
Eddiebx
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ah, so it might be a good idea to that this other one i saw that was ment for use in the wet locations, i think it said it was for laundry rooms and bathrooms. cool! i am gonna go radiator shopping tomorrow

#8
07-21-05, 08:36 PM
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No need for special

If they have baseboard with a heavier paint that would be great, otherwise a coat of automotive wax about once every couple of months helps a lot too. Most people either forget about or don't want to be bothered with the wax.