I’m trying to improve the efficiency of my hot water boiler system. I have old fashion free standing radiators. Has anyone had any experience with placing reflective panels behind radiators? Are certain materials better than others? I found one web site that offers a perforated panel that direct the heat up.
Thanks

 

Placing a reflector behind a radiator may help redirect the heat to where you want it, but the total heat emitted to the room won't change nor will the boiler system efficiency.

You can try heavy-duty aluminum foil.
Doug

 

check HD they sell 2 X 4 1/4 thick panels with foiled aluminum one side and paper backing the other cut those to slide behind each radiator foil side facing out.cork they say is the best insulation but is expensive.

 

HD also sells 3/4 in thick 8x4 sheets of Styrofoam with foil on one side. I cut them to fit and then ran foil tape around the edges. It does reflect the heat a little further into the room. I can now feel the heat hitting my chair that is in close range of a radiator. Sheet was something like $8 bucks.

 

Hi MaintDude, an outside wall, with good insulation, will typically be 2 to 4 degrees below the room temperature. Remove the insulation and obviously it gets much worse. The calculated heat loss typically uses room temp, but if the surface temp is greater than the room temp, you must use the surface temp. So, as the surface temp of the wall behind and above that radiator increases, so does the heat loss. With baseboard radiators, I have measured surface temps over 100 degrees 4 feet above the baseboard, room temp was 65 and outside temp was 20. So in that case the differential temp went from 45 degrees to 8o degrees, almost doubling the heat loss, all-be-it, for a limited area.

Placing a radiant barrier behind and up the wall above a radiator, spaced out from the wall (just like the heat shields behind a wood stove) will greatly reduce the surface temp of that area of the wall and equally important, reflect that heat out into the room. The foam in the foil covered foam acts as the spacer and will work just fine, usually 1/2" or greater. In remember finding at the time of my test, a product made for this that was cardboard bent to free stand behind a radiator with a foil surface.

What will it save? If you do this in an inexpensive way, it will probably pay for itself two or more times each winter, but that is a guess as there are many other factors that must be considered. But a typical home, I would say give it a try and let us know.

Now, if you are really interested in tinkering with your heat loss, there are MANY way to save a little here and there around a house and when all added up, they will make a significant difference. Post back if you are interested and I will be happy to get you going.

HH
Bud

 

thanks to all. these are great suggestions. i think we'll be off to HD soon.