LOUD air vent!

Pete123

I am slowly replacing air vents on my radiators as the old ones are failing. I just replaced the Main vents with 3 new Vari-Rite 35s.



In addition, I have been installing Vent-Rite 1As on the radiators. One of these new 1As causes the radiator to make a very loud "clank" when it opens and closes, which seems to be frequently.



This particular radiator is on the third floor.



I have the pressuretrol set to 2 with a negative differential of .75.



Thx for any thoughts!



Ps - how can I best CONFIRM that my pressuretrol is functioning?.

BobC

Venting and presuretrol testing

Try a Gorton vent, they are quiter than the Hoffmans, the trick is to select the hight one because they are not adjustable. You could try and find the maid o mist that comes with 5 screw in orifices (great for experimentation) just be aware there was a batch that had the threads cut wrong so watch out for that.



Ventrite 35's are a pretty slow vent, how long are the steam mains and what diameter is the pipe? You might be better off with larger vents, that would lessen the amount of air the radiators vents have to handle.



Can you adjust that pressuretrol any lower? How long does the boiler run when it first turns on for a heating cycle and does it cycle on and off at the end of the heating cycle? If you are lucky the boiler and system are well matched and it never builds any real pressure, stem can work at ounces of pressure. Does your pressure gauge read anything?



Pressuretrols are not very accurate, you can verify the switch portion by moving the silver arm above the piston up and listening for the click of the switch or for the boiler to shut down. That confirms the switch it does not mean all is well. The next step is to unwire the pressuretrol and remove it (circuit breaker OFF), then see if you can blow into the open pigtail. If you can blow into it easily the pigtail is fine, if you can't blow into it the pigtail is blocked and has to be cleaned or replaced. Even then you don't know if the diaphragm on the pressuretrol is good.



The problem with the stock 30 PSI gauge on a boiler is they don't work worth a damn down at 1 or 2 PSI where these systems operate. It would be a good idea to add an auxilliary 0-3PSI gauge so you know whats really going on.