Gushing Gorton

DNW

I just replaced Hoffman 4As with Gorton #2 vents on both mains and condensate return lines (2-pipe steam).  There are two loops in the house; on one of the condensate returns, water GUSHES out after the system is fully heated up.  I've turned the pressuretrol to minimum, but water still gushes out occasionally.  Probably about a gallon.  (The Hoffman's spit, but just in spurts, and not nearly as much water.

The gushing return is about 3 in lower elevation than the opposing line, and they join together near the floor; so I assume if I elevate the leaking vent to be as high as the opposite one, the leaking should stop. 

But - I thought the Gortons were supposed to stop water from "venting", as well as steam?

Mike Kusiak_2

Clogged wet return?

Is it possible that you wet return piping is clogged, restricting water flowing back to the boiler and causing it to back up to the height of the vents?



 Since you say that the gushing happens toward the end of a cycle, that would be the time when maximum water would have collected in a clogged return.

Jamie Hall

You should also...

check your cutout pressure.  If this is happening near the end of a run, then that's when the boiler is finally building some pressure.  It could be that it is simply that the pressure is getting high enough to back enough water up the wet returns so that it is getting to the elevation of the vent.

DNW

Leaking Traps?

Could leaking traps cause the return to be "pressurized", and forcing water out the vent faster than it can return to the boiler?

I'm trying to find a plumber who'll do any work on the steam system (in NC, this is tough!).  I doubt any cleanouts have been done since this boiler was installed in the 1980s (when it was converted from oil to gas). 

What about the Gortons, shouldn't they stop water?

Dave in QCA

Dimension B

The fact that the squirting water does not happen until the system is fully heated up certainly points to the likelihood that your pressure is too high.  Dimension B rules state that that your return piping,including the vent, must be 30" above the water line for every pound of pressure in the boiler.  Therefore, if your boiler pressure is allowed to climb to 2 psi, it will take a column of water 60" tall in the return piping to push the water into the boiler. 



It is very difficult, if not downright impossible to get a pressuretrol to work at pressures below 2 psi.  Therefore, you really need a Vaporstat on your system.  They effectively control the pressure at ounces.  6-12 oz is probably plenty of pressure for your system and then the return will work like a charm.



Regarding the Gorton vent, it is supposed to have a float device in it, but as others have indicated that their Gorton was squirting water, it must not work too well.  One option that you have is to put the Hoffmans back into the return side venting.  They venting needed there is much less than the mains because of the fact that the cast iron mass in the radiators has to be heated as the steam moves into the radiators and this greatly slows down the travel of steam.



Best option is to go for a Vaporstat.

nicholas bonham-carter

gushing gorton problem

definitely lower your pressure with a vaporstat, and verify it with a gauge [0-2 psi, gaugesrore.com].

some flushing off the wet returns would be good insurance too.--nbc

DNW

Vaporstat it is, then...

I'll try to get a Vaporstat and low pressure gauge installed, then.  The only plumber who'll actually return my calls, though, isn't sold on the low pressure steam concept, though. 

The returns are about 50 - 55" above the waterline, so I can see the problem with the 2 psi or above.

My Hoffman 4As are in pretty bad shape... any recommendation for a float vent appropriate for a condensate return line?

I've attached a diagram of the return piping, too.

DNW

Thanks...

for the flushing advice.  I'll need the plumber's help for that, he may need to install some drain valves.

Dave in QCA

Trane Direct Return Trap

You didn't tell us that you had a direct return trap.  If it were working properly, it would allow condensate to return to the boiler when the pressure climbed too high for it to return by gravity.

Here is a link to a publication that shows it quite well.  http://www.heatinghelp.com/files/articles/1392/26.pdf  



Your diagram of the piping does not show that there are pipes connected at the top of the Trane Direct Return trap.  There should be one line connected to the steam and another line connected to the return piping.  Of course, the bottom connection also connects to the return to the boiler and the check valves located in that part of the piping are critical to its proper operation.



If the direct return trap was working properly, your pressure of 2 psi would not be a problem at all.   A vaporstat would resolve the issue, and yes, residential 2 pipe steam systems were intended to operate at very low pressures and they do that just fine.



I can attest to the fact that low pressure works great.  I purchased a building that was origianlly a very large single family residence.  It has floor space of over 8,000 sq ft and a connected EDR load of roughly 1,300 sq ft of radiation, consisting of 30 radiators.   When I purchased the building, the boiler was controlled by a pressuretrol and the pressure was allowed to climb up to 2.5 psi.  There was also a condensate return tank and pump, necessary at this pressure to push the condensate back into the boiler.   Everything that had been done to the system in the last 30 years had been done by technicians that did not understand that the system was intended to operate at low pressures, commonly 20" Hg vacuum up to 12 ounces.   I have installed a vaporstat, it controls at 8 oz., and the system operates beautifully.  At this pressure the condensate will return by gravity and so the condensate tank set is scheduled to be removed.



If you observe your system, you will find that the steam fully distributes throughout and the radiators are starting to heat up before the boiler builds any pressure at all.  In fact, you will also observe that the pressure does not begin to build and start its climb up to 2 psi until all of the radiators are fully heated.  once this occurs, the rate of condensation slows, causing the pressure to climb.  So, if the pressure does not build until the system is fully heated, it obviously performs quite well at low pressures.

DNW

Trane Return Trap

Here's a picture of the Trane Direct Return Trap showing the connections.  In the background are the old Hoffman vents on the returns.  The vent on the right sits about 3" lower than the middle vent in the picture, which is on the return from the opposite loop.