RE: Taco Air Vent

jboissy16

When replacing the air vent, do you have to purge the whole system or can you just isolate it where the shut off values are. And also besides opening the vent 1 full turn do I have to do anything else to the system

billtwocase

have you

done something like this before? 

jboissy16

RE: Taco Air Vent

Just need to know if I can just isolate it, so I don't have to purge the whole system

billtwocase

yes

take the pressure off the boiler, isolate it, replace it, and turn the feeder back on. Make sure the pressure ends up 12-15

jboissy16

RE: Taco Air Vent

So shut the main off, shut all the values before and after the the air vent, replace and turn on all values? make sure after replace that pressure is 12-15, Nothing else? no purging

jboissy16

RE: Taco Air Vent

Just purge that section that I isolated for the air vent? correct 

billtwocase

is it

on top of an air scoop?

jboissy16

RE: Taco Air Vent

yes

jboissy16

RE: Taco Air Vent

yes

jboissy16

RE: Taco Air Vent

So just purge that section that I isolate, replace it, open the values and the main and that ir ?

jboissy16

RE: Taco Air Vent

Replaced, now Zone 1 heating acting funny.Supply line for that Zone really hot return line just barely warm. Heat in one room more then others, heating is still coming on in that room when t-stat is down/off??

jboissy16

RE: Taco Air Vent

Replaced, now Zone 1 heating acting funny.Supply line for that Zone really hot return line just barely warm. Heat in one room more then others, heating is still coming on in that room when t-stat is down/off??

kcopp

You may have....

disturbed some junk in the line. That may have lodged under a flow check valve. This sounds like phantom flow. If you can purge out the line in may get the junk off the seat.

jboissy16

RE: Taco Air Vent

So you mean it may be a freaky then, nothing to do with the air vent. So that junk is causing the heat to come on without the tstat on? So to purge that line do I isolate just zone 1 with the shut off and close the shut off right after thats zones circulaor and open the purge value?? anything else

billtwocase

2 things

first is can you post some picks of your system, and second, you never specified why you needed to replace the hivent. Is it leaking, not venting, or are you having a heating or pressure problem that you feel as though replacing this vent will solve?

icesailor

Air Vents:

I consider those air vents as an evil, as hateful as a product can be. I screw the caps down tight and leave them so they don't leak all over. And I've never had a system get air bound because of it. Only ones with the caps left loose and open.

You need to change the vents by "Catching it on the fly". By, putting a washing machine hose on the boiler drain, closing any vent on the system, and opening the drain on the boiler. When the system drops to zero, take new vent, which you have all ready with Teflon tape and paste already applied, and in one hand, unscrew the old vent. As it comes free, carefully insert the new one into the threads. As soon as you get it started a couple of turns, immediately close the drain valve on the boiler. Open the fill valve after you finish tightening the vent. If you do it quickly (and it doesn't need to be all that fast), you shouldn't need to purge the system.

If, when you are unscrewing the vent, water is squirting out of the threads, you haven't drained enough out. When the water stops squirting, Mother Nature is mad at you and trying to equalize the pressure inside the boiler/system by forcing her way into the system through the threads.