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Single to two pipe steam radiator conversion?

I recently purchased an '20s vintage mock tudor with a single pipe steam system. The house has settled quite a bit in several places, and as a result we've been told that we're stuck with the knocking radiators unless we replumb the whole system, as the pipes no longer drain at the proper angle. What I'm wondering is would it be possible to use my current radiators in a two pipe system? Would it even be worth bothering to do the conversion, since I have to replumb anyway?

Re: Single to two pipe steam radiator conversion?

How many rooms/total square footage are we talking about???

You wouldn't be able to use the present rads on a 2-pipe steam system, and with the cost involved, I think you would be better off with a forced hot water system---there would be more flexibility, less maintenance, and no worries about out-of-pitch flooring.

Check out the recent post below for similar issues and resources, and the "illustrated home" for diagrams of steam heat systems and forced hot water systems----click onto the + icon to get a bigger picture, or the "page" icon to get the next page of illustrations.

Forced hot water refit can be done with plastic PEX piping, which is a lot easier to snake thru wall cavities & makes for a quick install at less cost.


Re: Single to two pipe steam radiator conversion?

I've seen on TOH a single pipe to two pipe converstion. you can use your current radiators. the previous post in incorrect. to convert the radiators you simple have to Tap the return valve on teh other side of the radiator. most single pipe radiators are easily converted to two pipe radiators.

your problem will be installing the return pipe throughout the house. the TOH episode showed a unique solution to this problem. you should search for that episode. if i come across it i'll post it here.

we have a single pipe system in our house. we had to get a new boiler our first winter in the house. so we are sticking with the investiment for a while. if I had my choice and pulling up the floor to repipe the heating system i'm convert to baseboard and get rid of the cast iron radiators all together. they are space eaters and baby proofing nightmare.

good luck

Re: Single to two pipe steam radiator conversion?

I strongly disagree with the previous poster regarding coversion of a one-pipe steam system to two pipe.

Tanked must be quite confused if he doesn't know the difference between one-pipe and two-pipe.

There is no "return" on a one-pipe steam system, the same pipe is used to supply the live steam to the radiator and then direct the condensate back to the boiler when it cools via the same pipe.

To modify such a one-pipe system with rusted-in pipes and sections would hardly be worth the expense.

Re: Single to two pipe steam radiator conversion?

I beleive Tanked is correct - it sounds like the OP stated that the he wanted to convert from a one-pipe steam, to a two-pipe system. Though a two-pipe system cannot be steam, it can certianly be done as a forced hot water system quite easily.


Re: Single to two pipe steam radiator conversion?

Good luck removing the plugs on the other sine of the radiators They have been baked on there for over 90 yrs.


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