Steam radiator conversion

Pete_17

This is a good one. I have a customer, who was told by the G.C. on the job, that of course you can use your old steam radiators on your newly converted hydronic heating system. After being sand blasted and pianted, we are called in to install them. All three free standin cast iron radiators are strictly for steam. In other words, the sections are connected across the bottom of the radiator only. While explaining why this won't work, I make the point that you would have to have a bleeder on each individual section in order to bleed the radiator. For the record that's over 40 section. Well, the homeowner is so in love with these old radiators, that he wants to send them out to have each section drilled and tapped. The question therefore is, would it work? As the hot water flows across the bottom, will each section get hot through a gravity circulation or can the rising hot water trap the cold water at the top of each section? I have made the customer aware of manufactuters that make ornate radiators that fit this application and that I feel the whole concept to be absurd. However, the question of feasability has been impressed upon me.
Any and all answers, advice or general laughter is appreciated.

Peter Zanata
LMP NYC

Steamhead (in transit)

Typical know-nothing GC

This is why we don't work for GCs. They don't listen to us until AFTER their lack of knowledge has caused problems..... then they pay slowly if at all.

Tapping each section might work, but it would look pretty funny. And I doubt the water would circulate properly even if all the air was out. But what I really worry about here is leaks, from running those old rads at over 10 times the pressure they saw when running on steam. Same with the old piping if any of it was re-used. This is one reason why we don't convert steam to hot-water.

If they like ornate rads, Burnham makes new ones but they aren't cheap.