Clogged Pigtail: 1; Big Mouth Air Vent: 0

JohnNY

So, my pressuretrol was set for 1.5 PSI max.

But my pigtail was clogged, and so we went up to 4 PSI. This gauge picture was taken about a minute after I turned off the boiler:


Evidently the Big Mouth, though it's a loveable air vent, is unable to hold back some water the way some vents do:

Danny Scully

Don’t feel so bad @JohnNY, despite what anyone says, you can bet the gorton # 2 would be a shower at those pressures too.

Steamhead

Danny Scully said:

Don’t feel so bad @JohnNY, despite what anyone says, you can bet the gorton # 2 would be a shower at those pressures too.

Maybe if some dirt got caught in it. But this is why we don't spec Big Mouth vents on "B" dimensions.

STEAM DOCTOR

Don't shoot the messenger. They're really should not be that much water in the system. The solution is not to install an air vent that traps the water in the system. The solution is to eliminate the water and its causes. Customer is almost better off having water spray out this way. It ensure that they will eliminate the underlying problem.

Jamie Hall

Well, yes, @STEAM DOCTOR -- which underlying problem, in this case, was the clogged pigtail, which @JohnNY caught right away (no surprise there!). I'm with @Steamhead on this one.

gfrbrookline

Steamhead, are you saying we would be better off going with gorton's over big mouth's? My system works off of a vaporstat and cuts off at 14oz.

gerry gill

i personally like a main vent that would let water spill out in basement in the event of mishap verse sending upstairs. I've seen 30k damage to hardwood floors caused by flooded systems that leaked upstairs.

Steamhead

How about in a finished basement with no floor drain or sump pump? We see plenty of those...........

Jamie Hall

There is no such thing as 100% safe. However, there is much that can be done to increase one's margins.

On basement main vents, I'm going to have to agree with @Steamhead -- despite the much higher capacity of the Big Mouth, if there is a reasonable possibility that the pressure in the system may rise high enough to send water into the dry returns or mains where the vents are, I'd rather see vents with floats -- that is Gortons or big Hoffmans.

But -- it would be very good if water couldn't rise that high. Therefore, if you are not blessed with an operating vapour system control device (such as a Hoffman Differential Loop) which eliminates that problem (there are others which it doesn't eliminate) you really should have a second pressure control set low enough so that while water might get into the basement dry returns, it won't get any higher. Such as a pressuretrol set at say 1.5 psi. Which, as this thread points out rather well, should be on a different pigtail from the primary pressure control. If you are really paranoid, you can have a third manual reset control set at something clever like psi (12 feet)...

Shalom

The output of that thing is threaded, right? Maybe you could put an elbow facing down, and leave a bucket under it.