EDR QUESTION .

misterheat

What is the formula to find out what EDR a room requires if the room is 12' x15 ' 8 foot ceiling with 2 windows that are 24" x 50" currently has old radiator 25 H 11 section 5 column with an EDR of 33 i believe . I have a brand new 19 H 16 section 4 column rad not in use which i believe its EDR is 25.6 . This room gets pretty hot . Also with a brand new rad would i notice a different quality of heat compared to a 90 year old rad ? TIA

Jamie Hall

First, no difference in the quality of steam,

Second, you can do a standard heat loss calculation on the room -- just because it is just one room makes no difference. Any number of heat loss calculators available.

Fred

Is this a one pipe or two pipe system? I'm not sure it is worth the effort to change out a radiator for a 7 EDR difference. You can get the same effect by simple putting a slower vent on the existing rad (if one pipe) or throttling down the supply valve (if two pipe). I assume this is a steam system since you posted in "Strictly Steam".

vibert_c

@misterheat If you know how to use a spreadsheet, here is my example. Change your parameters.
vibert_c

vibert_c

oops, too quick on the trigger!

misterheat

Yes one pipe steam system . I have a small vent on it. The way my piping is off the boiler , this particular radiator is run directly from the header. The rest branch off the 2 inch main that runs across the basement. This was added many years after original construction in 1927 . I see your point about not being worth the effort. Just trying to find a place for this beautiful new radiator. I have a smaller room that has a 25 high 12 section 5 column which would be better in my bigger living room which 20 x 20 and only has a 25 h 10 section 5 colomn rad. So maybe I put new one I the other bed room and take The 12 section down to swap with 10section in The living room. The house was renovated years ago they removed all the radiators. I don't think they knew where each one came from . Thanks for chart and the knowledge.

Fred

Just keep in mind that changing or moving radiators isn't just physically moving the radiator. The spud in the radiator is matched to the supply valve. When you move or replace a radiator, you either need to move the valve or in the case of a replacement, you need to replace the spud and valve with a matched set, otherwise you will get a leak at the union.

misterheat

thanks . Yes the valves i bought are a matched set for each radiator i move . Got my spud wrench today . Have a sawzall and some cold chisels ready just in case . Hard part will be bribing my neighbor to help me move them Thanks again

MilanD

Agreeing with Jamie and Fred on everything, here's last week's "Ask This Old House" where Rich Thretewey keeps the spud while changing only the valve. Whaaaat??!!

https://youtu.be/HNnUO3-fj8Q

JUGHNE

As luck would have it, sometimes it must work out that way.

Years ago on ATOH, he was cracking a 2" union on a boiler.
My teenage son and I were watching this show, (kids would always remind me that This old house was coming on TV and we would go home early, they would rather watch this show than work late on Sat nite...go figure).

As he had a 3 & 4' wrenches on the union I told the son that he was turning backwards, as he started to grunt, the scene changed and the union was suddenly apart. My kid said I was probably the only one that noticed that before the scene change.
We all have done that, but not being PBS master pipefitter on national TV. I wonder if Richard T. ever got any feedback on that one.

RomanGK_26986764589

@MilanD I've swapped my bathroom rad for a bigger one and did not change the spud either. Just used the existing old valve and the spud that was in that radiator. Never had a leak or any problem with that rad.

MilanD

@JUGHNE , brainfarts happen... I can't tell you how many times I had to shadow-turn a nut on the bottom of the fitting or a bolt mouthing "lefty-loosy"...

@RomanGK_26986764589 , I get it. We keep telling people out here that spuds and valves don't match. I suppose the answer is more in line with try it and if it leaks, change the spud to match.

BobC

Sometimes you get lucky, if that was me I would have cracked the elbow of the nipple coming through the floor. But then the last thing I won was my draft notice in '67 where I was selected for the fickle finger of fate award.

Bob

Fred

I have moved a radiator too, using the old spud in the radiator with the existing valve and had no problem. Sometimes you get lucky but I think it has a lot to do with if the old valve and spud "match" the same manufacturer and period. I think we all know today's manufacturers don't custom match a valve to a spud. They make the valves on one line, make the spud on another and someone or something (robot) picks a valve, picks a spud, screws them together and boxes it. At least that's the way I picture it.

New England SteamWorks

Just went to a house where the previous owner tried exactly that. They swapped out both bathroom radiators. But there was no match. So they turned the valves off. Only way to remedy is new valve and spud.