Air vent maintenance?

Lurker_2

You're right in that the vents should shut off. To check if the vents are leaking steam, you can try holding piece of tissue paper over the vent while it's hissing and checking to see if it gets wet.

If it does, you'll need to either clean (boil in water and vinegar) the vent, which may or may not work, or just replace it.

As an aside, this happened with one of my smaller vents last year, but it could only vent a small amount of air, which wasn't sufficient to keep the boiler from shutting off on pressure. Of course, my boiler is oversized and it was a small vent. . . it did of course cost more in fuel, too, since the boiler run times were longer than they ought to have been.

-Michael

Bernard Smith

When my rads get hot, the rad air vents continue to hiss,: they don't shut off when steam hits them. Main vent is the same. Consequently the presure never rises enough to engage presuretrol so boiler runs constantly until thermostat shuts boiler off. pressuretrol set at .5 cut in and 1.5 differential. Are these vents shot or can they be repaired? I have 20 rads so it will be costly to replace all of them. What kind of maintenance can i do with vents to ensure they dont seize up in the future?

Bernard Smith

Anybody out there, steamhead maybe?

Bob W._3

Are you sure the steam has hit them and they are still open? If that was the case there would be steam coming out of them, and you would be putting make-up water into the boiler. Sounds like they are just venting more air. You could simmer the vents in a little vinegar on the stove. If your boiler is not building pressure is that all bad? It may mean that your boiler is operating efficiently, is well vented and therefore will run without building pressure until the T stat is satisfied. Thats the way mine runs. When I hear the vents "pulse" it means the boiler is surging and its time to skim (its new). Good luck.

Bernard Smith

Rads are hot all the way across and vent is hot. Yes steam has hit them and they continue to hiss. Also, it is bad that the boiler runs all the time until t-stat shuts it down. What is pressuretrol for apart from being a hi limit? isnt boiler supposed to cycle in order to let it breathe?