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edited November 2018

Ever wonder why the Dead Men painted so many of those old, free-standing, steam- and hot-water radiators silver? Yeah, so did I. I did some digging and came up with a delicious story for you. It goes like this.

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its interesteing that radiator cover manufactors claim that the covers actually help push the heat out into the room
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And now we are trying to leverage the coolest water we can to cover the heat load. All that so our little Munchkin mod/cons spit out as much condensation as we can get.

It would be interesting to try a radiator freshly blasted, then paint it flat black, then our color of choice. See that the return water does with those 3 schemes with the exact same flow and temp supply.
Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
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Jim_R said:

> @Solid_Fuel_Man said:

> And now we are trying to leverage the coolest water we can to cover the heat load.

I'm not sure of what the connection is but if these were installed oversized Re: To be able to open your window and get fresh air on the coldest day of the year..Then years later had them painted silver to reduce their output as people weren't leaving their windows open and we're overheating their homes , why wouldn't doing a 360 on the old de-radiation by Silver paint and let them slowly release their heat instead of just turning to condensate before getting the most out the steam ?
Jim

Are you talking about condensate subcooling? If you are, I actually have an interesting set of calculations on that.

If you could take all of the condensate recovered on a boiler and pull 40F out of it, you could capture another 4% of the energy or about 4000BTU per 100,000BTU input. (82,000btu/hr / 794btu/lb / 60min/hr = 0.2GPM) 0.2GPM * 500 * 40F = 4147BTU

The net result is that you decrease NET boiler output slightly and marginally increase boiler efficiency by about 0.2%.

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I was talking about water systems, I guess the article really is dealing with steam. My mistake.
Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
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edited December 2018
Really interesting. You have this in your steam books. I wonder given the fact so many "heating men" insist on running single pipe steam at 5 psig should we paint the boiler too? Na, they would just think the pressure should be higher, you know the boiler room is not as hot as it was. This is of course all in jest. How many of these geniuses never learn single pipe steam is the simplist steam heating system and the hardest to make work correctly. I have told people until I am blue in the face you have to follow the rules! I think we would all be better off if the property managers had to have some technical education not just a lack of education and a snotty attitude. Hey, I have a thought ,since silver paint cuts down on heat transfer maybe if we painted the property managers we would get 30 percent less hot air? 😜
• Member Posts: 1
Great story. Thank you for sharing. Do you recommend any paint in particular for heat radiators?