Painting Steam Radiators

Kjmass1

It seems like there is a lot of debate on the best paint to use on a steam radiator. I stripped and sanded one of mine and then sprayed Rustoleum white bare metal primer, followed by a coat of high heat white enamel. Only afterwards did I see that the primer was rated to 200 degrees, I've temp'd my rads out at over 215 degrees sometimes.



Only drawback with the high heat enamel is that it is more of a matte finish and I was looking for more of a glossy one.



- Do I need the high heat application for steam radiators?

- There was also a "high performance" spray application at HD..ever used it?



I'm thinking I could just spray a light coat of glossy on top...oil or latex based?



Thanks

Kevin

Paul48

Good Reading

http://www.heatinghelp.com/article/158/Radiators/1265/Does-the-Color-of-a-Radiator-Matter

Kjmass1

thanks

Thanks I read that as well. Sounds like non-metallic is the way to go.

icesailor

Interesting article:

Interesting article, but I don't think that the ability of the radiator to heat a room is the bigger issue in the life of today. I personally am more worried about the paint covering that will stay in place. Hot water radiators seem to keep their paint coating on. Steam and the hotter temperatures have a bigger problem. Customers get crabby when they spend big buckaroo's to have radiators cleaned, sandblasted and repainted. Only to have the paint fall off in sheets. I hate that, but I don't paint them. I've always left that to the paint people. The experts.

Is the question being asked is what is the best type of paint to paint cast iron radiators with? You probably have better luck with radiators where the temperature is kept cooler.

Which type of paint works best? Alkyd or Latex? Its getting harder and harder to get good quality Alkyd paints now because of the lo limits on VOC's.

vaporvac

flat

In other articles I've read it also says a flat dull coating is best. I've had terrible luck with oil and hi-heat paints and tremendous results with flat latex wall paint (good quality!) It's lasted great...many, many years. Plus, they sort of blend into the space which is nice since mine aren't at all fancy.

Kjmass1

-

Yeah I hear you...wish I could just pay to have them done but at $400 a piece it just isn't worth it (to me).



I guess I'd just like to hear of any real world experience from people painting them themselves, and if they had problems down the road. The last thing I want to do is paint them all and then have a problem with the way I did it.



Kevin

Kjmass1

well

that's not good to hear...did you roll or spray on the latex wall paint? Hot water or steam rads?

Jamie Hall

Like VaporVac

I have had very good luck with using the same acrylic paints (not like the old latex paints!) which I also use on the walls (mostly Benjamin Moore).  No problems with peeling or flaking.  Always flats.



Why do I do that?  Or perhaps more to the point, how did I get started?  Because if I match the radiator to the rest of the room, it just looks better!

ChrisJ

flat black

I'm curious about how a metallic coat on the wall side and a flat black coat on the room side would perform.

Dean_7

Painting Radiators

This is what I did. I had our radiators sandblasted then I painted them with Plasticote high temp engine enamel. Two were painted white and two were painted gray. This was almost 10 years ago and they look as good as the day they were painted. 

Kjmass1

great to know

I think this is the way we'll plan to process unless someone else has had different results. Thanks.

SWEI

Surface preparation

is 90% of a good paint job.

vaporvac

Reflective panels...

Chris, i don't know about reflective paint, but I imagine it would be at least as good as reflective sheeting. I put the double-sided reflective foam boards behind mine and it really helped.

icesailor

Old Dead Painters:

The old dead painters that I used to work with always painted them by hand. There was never a luxury to have then taken out, sandblasted and sprayed in a auto body shop..

They vacuumed and brushed all the fuzzies out between the sections and painted the radiators with "radiator Brushes", thin handled paint brushes that fit between the sections. They painted what they could get to and you could see. If you look at old painted radiators, painted by the Old Dead Painters, you will probably see that the backs aren't painted and every part of every sectional tube isn't painted.



Radiators that flaked and peeled because they got too hot got covers made for them.  Few had covers.

Harvey Ramer

Has anyone

tried Powder Coating any of these rads?



Harvey

jgonzalez1010

What's is the recommended method for painting rads without sandblasting.? Scrape loose paint, prime with antitrust primer and topcoat with white enamel paint. Does having a board of wood on top of radiator (hydronic) impede or enhance the heat output?

Kjmass1

> @jgonzalez1010 said:
> What's is the recommended method for painting rads without sandblasting.? Scrape loose paint, prime with antitrust primer and topcoat with white enamel paint. Does having a board of wood on top of radiator (hydronic) impede or enhance the heat output?

I just scraped with a thick wire brush, sprayed metal primer and then a white high heat spray paint.

I have wooden radiator covers and I think it helps direct the heat out. Heat only comes out the top slots not the vertical slits.

https://imgur.com/a/KW2sg

The heat has to go somewhere you're not going too post much

Koan

We had ours done this season with automotive 3 part epoxy. so far so good, but they smelled for a long time when heated.

Problem with powder coating is baking them in a furnace.

@ChrisJ silver on one side would cut down on the radiation on that side where as black or white would allow full radiation. The effect would still be less radiation out, so I think better all black or all white then a reflective back plate. The metallic paints do cut output but only the radiation part, not the convection part.

Koan

@jgonzalez1010 we had our removed and dipped in a commercial chemical stripper, then wire brushed before painting. They look like porcelain now.

Koan

@Jim_R I agree completely my approach was full blown at the top end. Being sensitive to the "no costs" policy of the site makes it tough to share that factor. I'll be happy to share other specifics. We have 11 radiators totaling 399 Sq Ft EDR spread between 3 floors.

We had 10 refinished for a total of 294 Sq Ft EDR. The eleventh was a 30 section 5 tube, and the company was afraid it would go in the dip tank and never come out. We figure its around 875 lbs. Still trying to figure out how to handle that one once heating season is over. Thinking I'll build a cart for it and soda blast in the garage and spray it on site. At least it is on the first floor. I think moving that beast as little as possible makes sense.
I did disconnect it and flush it out with two hoses. I also replaced all the steam trap cages (Hoffman 18 for the most part) and the crossovers thanks to @Sailah. He is top notch, very happy with the products.

I removed the 10 and moved them to the front porch for pickup. 3 on the third floor, 5 on the second floor. One on the second floor was 14 sections, 49 Sq Ft EDR. had a tough time getting that one up the stairs - guessing around 400lb. Some were flaking horribly and really needed work, some were not so bad but I did not know what was on them and they were all different shades of off-white. I took this opportunity to flush them out, which they seemed to really need, lost of rust water. One was actually a bit clogged with scale so I think it really helped that one. A company that specializes in this - Baltimore Finishing Works - picked up the ten rads, took them to their shop, stripped them in several chemical baths, rinsed them, wire brushed them, rinsed them again, sprayed primer and PPG hi gloss automotive 3 part epoxy off white paint - except the bathrooms were painted white. It took six weeks - got em back right after Thanksgiving - but they did a great job. He said he's been doing steam rads this way a long time and never had a complaint. They smelled bad for a long time - particularly when heated - but that's gone now.

Let me know if any other info would be helpful.

Henry

My father had two types of radiator paint: one was gold coloured and the other silver. He bought it from the radiator supply shop. In the early 80s, I still could buy some from only one place Shafter Bros. It a metallic flake oil based paint. If one looks at some really old radiators pre 1930, they were all painted this way. The backs were not painted.

Koan

@Henry - one important note is that metal flake paint actually blocks radiant heat transfer. From an efficiency standpoint, using non-metallic paint provides a higher level of radiant heat transfer.

Jamie Hall

Since this thread got revived... an update. It's now been almost 15 years since some of the radiators I painted were done. They were wire brushed -- where i could reach -- and scraped. Then they were painted with the same wall paints used in the rooms in which they are located (I used Benjamin Moore, but other major brands are fine) -- acrylic latex. The formulations have changed -- and improved some -- over the years. None of the radiators have peeled or chipped or discoloured anything evil of the sort.

I see no need to go to fancy high temp paints or epoxies -- or sand or bead blasting or powder coating.

Koan

I agree completely with your approach. It depends on what you want, the shape they are in, what is already on them, and how much time you have available.

I wanted a smooth long lasting finish, and as is they had some lead paint, some oil based pain and some latex paint. I could not trust the underlying finish and didn't want to wire brush lead paint. Most were in really bad shape and all needed to be flushed out anyway. I figured that even paying what I did it would have cost me more in time than I paid. I went with the epoxy because that's what the refinisher uses and would stand behind. But all that said... They do really look nice. I'll attach some pics.