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Leaky Steam Radiators

We have steam heat and a couple of the raditors leak at the bottom joints between the fins. I presume it was from contraction/expansion over the years (the house was built in the 1950's). Buying new radiators seems almost impossible. Is there a way to fix the leaks?

Ron remodeler
Re: Leaky Steam Radiators

Not easily.

Radiators are sectional and have tapered nipples in between each section, When they start leaking it will be from rusting through or loosening up.

If your radiators have through bolts they can be tightened, try that but the rusting may have already occurred to affect the tapered seal. If they are rusting through chances are even if you could mix some Porter Seal into each radiator, and run the heat that it probably would re occur later.

I have taken radiators apart and removed the leaky section but have never prevented leakage with an easy fix with much success.

Ron remodeler
Re: Leaky Steam Radiators

Oh and by the way radiators can still be found at some local metal scrap yards. Buying them new is very expensive.

Re: Leaky Steam Radiators

Thanks. I've bought a used radiator once, and was lucky in that the seals were OK. Bit of a gamble I thought. I'll try the Porter Seal first, then tightening the through bolt. Bit leary of taking it apart.

When taking one apart, how difficult a job was it? Did you replace all of the seals, or just where the leaks were? Torque wrenched, or just by feel ?

Ron remodeler
Re: Leaky Steam Radiators

The seal is a metal to metal tapered nipple no threads.

To take a radiator apart you must lie it on the floor on a rag or some plywood so you don't scar the floor and remove the retaining rod bolt that holds it together.

Get a small sledge hammer, engineers hammer or mallet and a good cold chisel. With a firm blow and the chisel placed at the division between the sections you should be able to POP the seem open.

Which side the nipple gets stuck on will be a chance occurrence. They are removed with the same loving touch and if they get scarred during the process must be filed smooth to work again. Be careful as cast iron can crack if hit wrong. Usually its the radiator section that rots through and not the nipple.

Do not use petroleum products as that will get into your boiler water and prevent steam from occurring correctly.

Porter seal is safe in a steam system but is more of a chance method at best but sometimes can work.

If you do have to clean your boiler water after any of this there are product sold at plumbing supplies that work well.

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