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replace slantfin w radiator

I am going to be remodeling my bathroom and would like to replace the 4' section of baseboard and replace it with a regular radiator that I will recess into the wall to gain space. the system is hot water baseboard. is there anything special I need to know. my plan follows:
step 1 drain system
step 2 remove section and plumb as needed
step 3 install new radiator
step 4 fill/bleed/ check for leaks.

is there any special radiator I need to ask for from the plumbimg supply or just let them know how many sections and that it is for a hot water system.

thank you

Re: replace slantfin w radiator

You would first have to determine how much heat in btu's/hour the bathroom needs to keep it warm and then order any convector that puts out that amount of heat.

If you have a 4' length of baseboard in there now (assuming it's standard output & not high output), the heat output for this is 580 btu/foot per hour X 4' = 2320 btu/hour.

Thus, it sounds like the bathroom is underheated, unless it's only 40 square feet, or so.

Determine the heat need of the bathroom by multiplying its length times its width (assuming 7' ceilings) and multiplying the result by a heat factor of 60.

Example: thus, an 8' X 10' bathroom = 8 X 10 = 80 sq.ft. X 60 (heat factor) = 4800 btu/hour needed to heat this bathroom.

Radiator sizing:

Radiators bought new will have the heat output included with the sales literature---you can buy one used for cheap at a demolition yard, used plumbing supply house, etc.

For a used radiator:

Assign 170 btu/hr for each sq.ft. of radiator area.

Thus, a 28 section rad 2' high & 1/2' wide = .5 X 2 = 1 sq.ft. X 28 = 28 sq.ft. X 170 = 4760 btu/hr heat output for this radiator.

If you have a very small bathroom you may be able to use a second hand cast iron rad, otherwise the large ones weigh over 400 lbs.

It would be lots easier to consider installing a kickspace heater (site below) at the base of the vanity cabinet, or built-in flush with the wall near the bottom---these units tie into the copper piping where the baseboard was, are very small (12" X 12" X 4" high), yet put out 4k to 5k btu/hr, even for the small ones & cost ~$60-$100---ideal for a confined space like a bathroom.

Aside from Beacon-Morris, kickspacers are also made by Burnham, Myson, Nutone, Broan & others---get one that has a quiet fan---while at the Beacon-Morris site, also click on to "products/residential" to view other options such as high heat units, convectors that can be side-mounted, etc.

Other options would be a stainless steel towel-warmer/radiator of the btu/hr rating mentioned--TOH plumber Richard Trethewey has a video showing an install of this item---use the site search to find the video.

Please post back with bathroom dimensions.


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