Gorton #C's vents not closing; Is there some 'prep' you are supposed to do?

AJ_Marks

I have 10 radiators in my home. Most vents are Gorton 6's, but I have tried 2 #C's on the 2nd floor. In both cases the C's do not seem to close. They get stuck partially open until slightly jostled. 6's don't seem to have the same problem. Is there some "prep" one is supposed to do to break-in a vent so that it seats or closes better? Thanks.

Mark N

I assume they are leaking steam. Have you tried rinsing them out. Might be some crud in the valve seat. What is your operating pressure? Gorton C's are a large valve, how big are the rads?

KC_Jones

Agreed that is a large vent. I experimented with large rad vents and had some minor issues because of the steam rushing into the rad so fast, caused some spitting and the vent had difficulty closing. Switching to a slightly smaller vent eliminated the problem. Are you seeing any water spitting?

AJ_Marks

Yes. Definite spitting. The radiator is not large, because they are just 'steam convector radiators', but this pipe run seemed far enough for a #C. Sounds like if the #C is too big, it might "sweep up" crud or moisture which then cause it not to close (?)

Mark N

Convectors need straight shank vents. Using a large vent like a C can cause imbalance in your steam distribution. The faster you vent a rad the higher the velocity of the steam in the riser. If the velocity is too high the condensate can't drain back causing all types of problems.

AJ_Marks

OK. Thanks for help. I'll downsize the C's to 6's.

Mark N

Are you using straight shank vents? Also, a convector doesn't contain much air, a 6 might even be too large.

AJ_Marks

Yes. Straight shank, 1/4". I have 7 #6's and 1 #5. They seem to be doing fine. The 2 #C's were problems: splitting, not closing. I had previously swapped out 1 of them with a #6. But before I swapped out the other one, I thought I should check with HeatingHelp community to see if there was some "prep" or "break in" that I should have done with the valves. (all 10 vents in the system are newly replaced.)

KC_Jones

Is all your main venting in proper order? You need to make sure the main venting is tuned before getting the radiation venting tuned in. In general you should start with small vents and then work up as necessary. Say #4 on first floor and then #5 for second floor as a baseline. After that if you find you need more heat in one room then you can increase the vent in that room. Did you happen to buy this? A lot of good information about venting in this eBook.
http://store.heatinghelp.com/product-p/300.htm

AJ_Marks

Yes. Thanks. I did review e-book on venting with calcs. The mains are doing well. Given the pipe runs to the 2nd floor, a couple #C's had seemed good (based on e-Book and supported by info from Gorton.)