Help Main Vent In Basement Spraying Water!!!!

HotChocolate1947

I'm freaking out! I woke up and found brown water in my basement. The water was from my heating system! There was a big pool of water. The heating cycle was running at the time. I saw water spray from my main vent. I quickly turned down the thermostat to stop the heating cycle. Here, the strange part. It happened the previous night. I cleaned up the mess and it ran fine during the day. When I woke up this morning, I found another mess. Why would it run fine during the day and spray water at night. It's colder at night of course. This would simply make the heating cycles more frequent, right? It wouldn't make a "more intense" heating cycle, right? I have a steam system powered by an oil furnace. I checked the radiators and their valves. They all seem fine. In fact, the leaky main vent seemed fine during the day. I can hear it hiss and letting out pressure. I'm at a lost. I don't think there's a clog in the system. I checked the pig tail on my furnace; I think it's reading the pressure correctly. The only thing I can think of is replacing the main vent. Here's another strange thing. I replaced a different main vent across the basement that was leaking a little bit of water?!? What are the odds of 2 main vents failing??? Thank you.

Intplm.

Main vents will sometimes spray a little water. From the sound of it, yours is spraying too much.

I would check the water level in the boiler. Is the boiler set up for auto-feed or do you manually feed make-up water to the boiler? Is the boiler surging? Might need to clean or replace the vent.

Waher

Clean your pigtail and check if the boiler is flooded.

HotChocolate1947

The water level is normal. It's a manual feed. After spraying water over night, more water actually had to be added to bring the water levels to normal. To be honest, all I can think of is replacing the main vent. Sadly, I couldn't buy a new one on Sunday, the 1st time it happened. I should be able to get one today. What are the odds of having two main vents going bad within a few days apart? Thank you for taking the time to reply.

dabrakeman

Yes the main vent could be failed open. Also did you make sure all the condensate had returned to the boiler before refilling to normal level in the sight glass? Send us some pictures of your boiler from a distance at a few different angles. Also send a picture of the main vents. Most vents you could test by taking them off turn them upside down and blow through it. You should not be able to blow through it when it is upside down. You should be able to right side up.

HotChocolate1947

Yes. I looked at the pigtail and it seemed fine. As for the water level, I waited for the system to cool down before I added water. I also checked the water level before I went to bed It seemed fine. Again, the system ran all day Sunday fine. The only real difference I can think of is that the weather was colder in the evening. It was 40-50 degrees during the day. It was 30 degrees in the late evening. Not sure why that would make a difference??? Maybe, the main vent is still working intermittently and running more often in the evening just increased the odds of seeing the failure????? The heating system is over a decade old and running fine up to this point. It's not a new "installation" with the usual hiccups. You had a good idea about checking the vents.

Steamhead

@HotChocolate1947 , when replacing a main vent, it helps to know the length and diameter of the steam main it serves. Many older vents were sized for coal-fired boilers and are too small for efficiency with oil or gas. Post the steam main's length and diameter here and we can tell you what you need. With a proper vent you can save a considerable amount of fuel.

ethicalpaul

If it was shooting brown water, that is 100% guaranteed to be water from the boiler (not from condensate).

I can say with a high level of certainty that your boiler is surging. Was anything changed with it recently? Any work done on it? Oil in the water, or too many weird dissolved solids in the water can cause it. Bad boiler piping can make it worse.

When your boiler is running, keep an eye on the gauge glass and if it dramatically drops (like more than 2") then that is the water in the boiler getting into the main lines.

It's 100% not your main vent's fault, although your main vent might now be full of rust and no longer work, so be aware of that.

HotChocolate1947

@ethicalpaul, I suspect you're correct. The only recent change is replacing the 1st main vent which was leaking some brown water. It then stopped venting. I knocked on it and it came loose. It seemed to work fine for a few days. Then, it leaked a bit of water again. I was feeling a little uneasy about the fact it got stuck in the closed state so I just went ahead and replaced it. Again, things seemed fine for a few days until a different main vent started to spray water over night. It ran fine during the day. Then, it sprayed again and I found it this morning. I did a tune up in the spring and I cleaned out the pig tail last winter. The heater wouldn't turn on. I don't know what could have gone wrong to cause the surging???!!??

HotChocolate1947

To be clear, the 1st main vent was only leaking a little bit of brown water. The second one, the current one I'm dealing with, is spraying a lot of water. I checked the 1st one and it seems ok; but, to be honest, I cant' really tell if it's venting. With all the noise of the furnace, I have a hard time hearing the venting. This whole thing is a big mess :( Maybe, I should have left well enough. Probably it would have happened regardless as the temperatures started to fall.

Jamie Hall

I quite agree with @ethicalpaul up there. Surging is much the most likely way that water can get into the mains and as far as the vents in enough quantity to spray out (assuming the vent is not a BigMouth — those have no float, so they can spray quite enthusiastically in some installations). The only other two possibilities I can think of is a boiler which is badly overfilled or real problems with the near boiler piping.

pedmec

I would lean more toward a plugged return. longer run cycles happen overnight due to the ambient temperature drop. The longer run cycles cause the condensate to stack up in the return until it gets the air vent. it's not a complete plug though. It would slowly creep back to the boiler. Watch your water level after the thermostat has satisfied and the boiler has shutdown. it will be low (not low enough or a delay in the water feeder) and slowly the condensate will come back.

HotChocolate1947

@pedmec I like your hypothesis. It explains why the system seems to work fine in the day. If it is a plugged return, do I call in a plumber to fix this?

pedmec

I would recommend it. Sometimes you can lightly tap on the offending return to get it loose but you would need to do so cautiously as you don't know the condition of the return. Plus you haven't posted pics so we cacan'tt tell you where to tap.

ethicalpaul

the plugged return is possible. To tell the difference, watch your boiler during a long call for heat

Does the level go down steadily over time? Or is it a fast drop?

After the call ends, does the level go back to normal relatively quickly or does it take more than a few minutes?

neilc

oh for a picture of the boiler, and of the sightglass,

HotChocolate1947

Sorry. I've been dealing with a family medical emergency. When it rains, it pours!!! I actually caught it spewing water last night. I heard the heating cycle start and went to the furnace to watch the sight glass. The water level was clear and within normal levels when it first started. It eventually turned brown as the heating cycle continued. I watched it bounce 1/2 an inch to start. Then, it worked it's way to 1 inch and then to 2 inch. I didn't have a timer but I would say the process took a few minutes maybe five. Then, it started spraying water. Brown water. I ran upstairs to turn down the heat to stop the heating cycle. I looked at the sight glass and by the time the furnace stopped. It quickly went back to the water level that it was at the start, as far as I can tell. Thank you for all the good information; you guys really know your stuff. You've been very helpful during this stressful time. I'm calling in a pro to help me. This is way beyond me and with all the other pooh I have to deal with, I simply can't handle it. Wish me luck guys. I really need it.

ethicalpaul

It sounds like just surging. It's very easy to correct, don't sweat it. Have someone skim it to remove the oils from the surface of the water, then after skimming you will have to drain several gallons anyway which will clear out a lot of the remaining dirty water.

HotChocolate1947

@ethicalpaul I hope you're right. Thank you for your help.

HotChocolate1947

Drained all the water from the entire system and replaced the main vent, I don't trust it anymore. The surging is gone and so far no water spraying. Thank you for all of your help. Maybe I can get a good night's sleep. I turned the heat down to 58 degrees last night. Crossing my fingers and hoping the problem is finally fixed.

AdmiralYoda

@HotChocolate1947 a few thoughts come to mind:

1. Surging can be caused by a number of things….but usually the culprit is oils/contaminants introduced after some work has been done, like new black piping/fittings/etc. The other, though less common is a filthy/sludgy boiler. Mine will do this if the water gets too nasty.
2. Draining and flushing the boiler is a good first step to get rid of the gunky water, if that was the cause. Mind sharing a picture of your sight glass?

Also, time and time again we've seen that setbacks don't always work so well when it comes to steam. When you increase the temp, lets say from 58 to 66….the boiler produces steam and in short order the radiators are filled and won't get any hotter. Your boiler will continue to run but will just be wasting btu's.

I have an old house and I've found that it costs less money to maintain the house at 68 than it does to essentially turn it off at night and let it work its butt off to get warm again. And I'm more comfortable too.

HotChocolate1947

The sight glass is crystal clear. Then, again it was crystal clear before the draining. It was clear after sitting without running. Oddly a few years ago, the sight glass was dirty, even after cooling down. I used to drain the furnace water on a regular basis whenever I saw the water dirty. Lately, the water looked clear. Go figure? As for setting the thermostat to 58, I did it to prevent the basement from flooding with brown water over night. I wanted the fewest heating cycles as possible. It got down to 35 last night. I used a space heater.

ethicalpaul

Don't drain on a regular basis. You will just create more brown water by introducing fresh, oxygen-rich water.

If it keeps surging, you may have to skim it, not just drain it.

HotChocolate1947

Wow! Thanks letting me know. How do skim oil from a furnace? What do you do with the byproduct? It seems like something more suited for a pro.

ethicalpaul

Just a small note, it's a boiler, not a furnace. If you call it a furnace, contractors will think you are clueless 😅

Skimming is rather simple, there are lots of videos about it, here is one

HotChocolate1947

😧I am clueless. I don't know how I got into the habit saying furnace. All the diagrams I reference say boiler. I'm going to be clueless again. Should I go ahead and wipe down pipes with paper towels and water to remove all the dried brown water? The stuff isn't going to corrode my pipes or anything, right? Yeah.. I am clueless.

Jamie Hall

I wouldn't bother — but then, I'm not down in the basement enough to notice… and all the mains are insulated anyway. But no, it won't cause further corrosion.

ethicalpaul

https://forum.heatinghelp.com/discussion/comment/1822859#Comment_1822859

It's fine to be clueless, you just don't want the folks you invite into your home to work on your boiler to know that you are, at least not immediately 😄

STEAM DOCTOR

And even more important, you don't want the people that you invite into your basement to do the work, to be clueless. It happens you know

HotChocolate1947

Thank you everyone for being so understanding. I'm glad this isn't Reddit. People would be throwing so much pooh my way.