edr capacity of 1 in angle steam valve

Robertw

Ok so i have a spitting air vent on a steam radiator. Systems clean. 1 inch riser to it on the first floor and the radiator is 30 edr. Burnham heating helper book states 25 edr for a 1 inch riser so i know im over that. But if i remember right Dan mentioned in his lost art of steam heat book that there was an overlap on valve size. Referring a situation where the riser capacity of 1 inch is greater than a 1 inch angle steam valve can handle.

Any one have that capacity number handy? My lost art book isnt with me.

Thanks for any help

ethicalpaul

How much is it spitting?

I often wonder about these spitting situations…I think much of the time it is the vent's fault, where it is allowing steam to pass.

For your valve to be the problem, it would basically be the entire radiator filling with water and I think that would be more water than "spitting", but different people have different ideas of these terms, that's why I ask.

I'd be very shocked if your 1" valve couldn't handle 30 EDR. Everything in steam seems to be 2-4 times conservatively engineered. Which reminds me, is this something you see only when the radiator is fully hot?

Robertw

Starts spitting after roughly half the radiator is hot. Sems like the higher speed of the steam coming in wont allow for counter flow of condensate. I've dropped the air vent size to slow the venting but cant find a happy medium between not enough heat and leaking vent

Steamhead

Check the valve- sometimes the washer disc comes off the stem and blocks the hole, so condensate can't get back down the pipe. You'll need to disconnect the rad and look inside.

ethicalpaul

OK so the vent is not steam hot it sounds like. How much water is exiting the vent?

I can't picture how the incoming steam could be stopping the water from exiting unless you were experiencing the radiator actually filling up with water.

If the bottom third of the radiator were actually full of water from the steam preventing outflow, I would think there would be significant gurgling sounds, etc.

What model vent is spitting? Please don't say Vari-Valve 😅 If that's what you have, I'd say switch to a Gorton or Maid o Mist

Robertw

gordon valves. its banging a bit as well when she spits. spits enough water to be a nuisance until the valve closes completely. Then obviously no heat. The slower valves seem to help get more heat to the radiator but cant find a sweet spot. This is why i went to charts. Unfortunately Dans book isnt with me. I had this issue a few years ago on another job and had to change the 1 inch angle valve to an 1 1/4 valve and use a bushing to the 1 inch riser and it solved the problem. Using the charts in the lost art of steam heat i noticed that a 1 inch angle steam valves edr capacity was lower than the riser's capacity. That's where i think i am now.

I'll dig up the book when i get home i guess and figure it out.

EBEBRATT-Ed

Good luck trying to find valve capacity. I looked up a few valves including Hoffman and Watts and found no sizing information.

I think you had a good idea putting an 1 1/4" valve on with a bushing on the riser.