Converting cast iron steam radiators to hot water

Terrival

My husband and I own a 1929 Sears & Roebuck house on Long Island. We are embarking upon a major renovation which will double the square footage of our home and we have been advised that it would be best to replace our 1 zone steam system with a 4 zone hot water system. Yes I know radiant is nifty but money is an issue.

My problem is what to do with our existing radiators. The plumber we're working with would like to ditch them all and install conventional base board. I have 2 problems with this. First, I don't like the look of baseboard and second I hate the thought of throwing away something original to the house that could work really well. I've been told that to convert a radiator I'd have to have it flushed out (don't know where and don't know how much it would cost)which might not be successful and that the fittings could crack while attempting to attach a return line. Three of the radiators in question are Sunrads and I was told by one contractor that I should try to keep them. My goal is to have radiators on the first floor and baseboard upstairs.

So my questions are:

Is it worthwhile to try to reuse my radiators or am I just wasting my time and aggravating my husband?

If it is worthwhile, can you refer me to someone who flushes radiators and/or can give me more information about this?

If it is absolutely not worth the trouble, where can I give away/preferably sell my old radiators? I'd hate to see them tossed into a dumpster.

Please help me. I don't know much about this stuff and everyone else involved in the project disagrees with me. I'm starting to cave.

Terri V.

Mark Hunt

Call this guy


http://www.heatinghelp.com/getListed.cfm?id=210&Step=30

He is fantastic!

Mark H

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Steamhead

Why not

keep the original steam system, and install a second hot-water boiler for the addition? That way, if one conks out, the other will still run, and the entire house won't go cold.

You could also heat the addition with steam. It's easier than it sounds- ask me how I know that.

And I know you'll be able to find some beautiful radiators to go in the addition!

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

Terrival

Too Late

Thanks for the recommendations to keep or extend my steam system but the hot water is a done deal for a variety of reasons. The most important reason being that I'm under contract with my contractor and his brother the plumber who says hot water is the way to go. Additionally since we needed head room for our new basement bathroom a big chunk of the steam pipes has already been cut out. I should have posted to this site months ago. Perhaps I would have made different decisions.

So my previous question remains. What's best to do with the old radiators?

Terri V.

Mike T., Swampeast MO

Look carefully at your radiators. You will see that the sections are "attached" across the bottom. If they are attached across the top as well, they can be used for BOTH steam AND water.

If suited for water KEEP THEM and USE THEM!!! You will have to verify that their size is still suitable for water but in most circumstance it will still provide plenty of heat even with the [cooler] water.

Test under hose pressure (WAY higher than it will EVER see in an operating system), flush a few times changing the position of the radiator, plug the air vent and drill/tap for an air bleeder near the top (most rads have little "flat place" for such).

Lots of "man handling" and some heavy work requiring a good long pipe wrench (and likely "breaking" bar) to remove the old tappings, but considering it was an "engineered" system to begin with, it should still be reasonably well balanced when convered to water--provided of course it was reasonably well-balanced to begin with.

Investigate and use TRVs if budget will at all allow.

Boilerpro_3

An addition to Mike's post above...

On one pipe steam radiator conversions, I've found it unneccesary to remove the plug from another tapping in order to provide a second pipe connection. On smaller to medium sized radiators, I plumb a 1/2 inch copper return line up to the old air vent location and then use an 1/8 inch pipe nipple to go into the radiator at the old one pipe steam vent location. Then drill and tap the radiator at the location near the top, or drill and tap one of the plugs at the top, for the manual air vent. For larger rads, you can use both the old steam vent tapping for a return and the tee up to the new air vent tapping (the vent goes on top of the tee), or just tap the lower plug with 1/4 inch and use a 1/4 inch pipe nipple connected to you new 3/4 inch return line. Short 1/8 inch and 1/4 inch pipe nipples provide just the right flow (assuming a 20F drop in water temp across the radiator) for the rads with most new higher head residential pumps.... B& G nrf-22, TAco 007, etc. If your plumber doesn't believe, have them do the math. By teh way, its best to not just tap the top of the rad for both the return and vent, because the radiator will tend to heat at a diagonal, reducing heat output (see 2nd photo of large radiator).