Vents woke up on the wrong side

malex

<span style="font-size:12pt">I recently replaced my very old main vents and put a Gorton #2 on the 55’ main and a Gorton #1 on the 15’ main. I also replaced all rad vents with Gortons and it seemed to be working well. Up until this morning. In my upstairs study the radiator vent starts hissing and making a lot of noise but then goes quiet as the radiator got saturated (this one is on the 15’). I then hear a loud hissing and gurgeling from the second bedroom upstairs (on the 55’). This is one of those built in fin-tube convectors with a sheetmetal front. It’s so bad that I turn it off. Then the master bedroom rad (on the 55’) goes off into a frenzy. Down stairs all is pretty quiet except for the last radiator on the 55’ in the dining room which is making some noise, but not as much as the ones upstairs.</span>

<span style="font-size:12pt">In the basement, the Gorton #2 is dead quiet. I feel it and at the connection it is piping hot but the body is luke warm. Is on a short antler due to clearance issues. The Gorton #1 is releasing air intermittently and is hot all the way up to the top. </span>

<span style="font-size:12pt">I watch the boiler as it comes back on for the next wave. It is set to cut out at .5+1 but pressure goes just past 2psi  before shutting down. I have observed this before and assume it is the pressuretrol that is not calibrated correctly. During this cycle I check the Gorton #2 and I never hear a sound or feel any air. It is still luke warm on the body while the connection is hot. Gorton 1 is pushing out air and is hot. As the cycle ends the pressure goes negative.</span>

<span style="font-size:12pt">I know the first question I will get is: “it worked before, what changed?” The only thing I can think of is the temperature. Yesterday it started getting colder on Long Island and this morning it was freezing. Could that be causing the boiler to work harder and reveling an issue that was there before but not manifested because the milder whether didn’t push the system hard enough. It also seems relevant that it is mainly upstairs and I noticed that the raiser to those radiator are all smaller size than for the first floor (also less distance for the air in the raiser to travel). I am planning to insulate the mains and riser soon but has not gotten to it yet if that has anything to do with it. Lastly, I’m wondering if Pexsupply sent me a bum Gorton #2? It did have a couple of scratches on the body but the threads were clean so I’n not sure if it was a returned item. I did the blow test before installing it and it seemed to work.</span>

<span style="font-size:12pt">Any ideas are very appreciated.</span>

<span style="font-size:12pt"> </span>

nicholas bonham-carter

noisy vents

at 2 psi, your vents may be closing before the air has escaped, if you have a good low-pressure gauge [0-2 psi, gaugestore.com], then you should add main venting until the back-pressure at the start of the firing from cold is about 2 ounces or less. unfortunately, pressuretrols are not very accurate at the low pressures we need. a vaporstat i feel is well worth the cost, but i am sure you will need more main venting, otherwise you will have short-cycling.--nbc

Long Beach Ed

Let's take a stab at this...

Too much venting. 



I know this is contrary to what is preached here by many, but this is causing the problem. 



We can phrase this several ways, but the solution is to tolerate a problem on some days or vent more slowly. 



Here's what I believe happened and why it hasn't been an issue up till now.  Malex hit the nail on the head when he spoke of temperature.  The colder a radiator and piping is, the more quickly it condenses steam.  The more quickly condensate is produced, the more water that the pipes must handle against the flow of rushing steam.  The velocity of entering steam (which is moving really fast thanks to the huge holes in the vents) blocks the exit of the condensate and shoves it back into the radiators.   This is what causes the hissing, rushing and gurgling sounds.  Modern boilers steam FAST, and that steam gets out there fast when the near-boiler-piping is correct.  This exacerbates the problem.



If you vent radiators and mains FAST, you often get gurgling and wet steam noises on frigid days when the system is recovering from setback or just turned on -- when the radiators are really cold. 



On mild days or when the radiators are already warm, this may not every show it's ugly face. 



Your choices:  Live with it, or slow down the venting in the problem areas.  You can also increase the pitch or pipe diameter in the problem areas.   You have to either reduce the condensate load or increase the condensate handling capacity of the piping.  Some huge radiators simply cannot be helped.  They must be vented slowly.



Find the happy medium.   That's what balancing steam is all about.  If it was as easy as putting vents with nostril-sized holes everywhere, they wouldn't make vents with pinholes.

nicholas bonham-carter

too much venting

ed, are you referring to the radiator vents? i would think that where ever you have radiator vent noise, you have too much pressure, and not enough main venting.

if you have the right gauge, you can get a good idea of whether you have too much pressure, or inadequate main venting.

we must remember that it is not only the air in the pipes and rads which must be allowed to escape easily, but also all the air in the boiler steam chest.--nbc

malex

venting slower

LB Ed, to NBCs point, are you suggesting slowing down the mains or just the rads? I have Gorton #4s on most rads 2 #5s (on a large first floor rad at the end of the long main (north facing wall) and on a second floor rad) and 1 #6 on the master bedrom (2nd floor, second to last on the long main on a northern facing wall and still tend to last to heat up). What sizes should I be using? Are the #4s too fast even?



Should I move the Gorton #1 to the long main and get a slower (Hoffman?) from the short main? (I see a Ebay add for a better used Gorton #2 in my future).

Would insulating mains and risers alleviate this problem? I still plan to do it but knowing it will help with this noise would increase the motivation factor.

So nobody thinks I have a bum Gorton #2 that is forcing all air to go through the rad vents? 



Sounds like my best bet is to wait for global warming.



NBC - I do have a Vika 3psi guage. What should I be looking for?

Appreciate the input!

nicholas bonham-carter

venting backpressure

i always choose the biggest main vents, with the smallest radiator vents first, and then go up a size or 2 if needed.

look at the gauge, when the boiler first begins to build steam, and the air is escaping, mine reads 2ounces at that stage.

as the boiler continues to steam, and the air has escaped, then the pressure will rise [almost never to my cutout-point of 10 ounces].

i only have large radiator vents at the top of risers which have tended to get steam later, but i have many gorton#2's on the dry returns [3 on each]. by the time the steam enters the tall risers, all the main air is out, and at low pressure i am not making much vent [hoffman 40] noise, unless it is sub-zero and dropping outside.  

so i would say that if you are hearing noise, then the pressure is too high [over-sized boiler], or not enough main venting. don't sell your old ones, just use them alongside the new gorton #2's you will buy.--nbc

malex

Must pick a side

NBC - the pressure stays below .5psi for the longest time but then (I assume when all air is out of the mains) the pressure starts climbing slowly. The cut-out is set to 1.5psi (lowest possible) but it does not cut out untill it passes 2psi but the vents were howling well before then. Maybe it is time to invest ina vapor stat because the pressuretrol does not seem very accurate. So in your oppinion I should add more venting to the mains but possibly slow down some rads?

BTW - I do not have any dry returns, both mains do a 90 down into the wet return after the last riser if that makes a difference.

Also, the first half of the long main is counterflow and the second half is parallell flow. I know this because the main makes a 45 up to get over the center hall beams (so any riser before that point flows back to the boiler) and then a 45 down (so any radiator after this is paralell flow) and end in a wet return.

OK - so there are two camps, the fast venters (NBC) and the slow venters (Long Beach Ed). Now I just have to figure out who's ideas is right for my application (they obviously both work in certain applications). 

crash2009

Night-Time Setback

If everything has been working OK until now, maybe it's time to simply adjust the thermostat.  If you have it set to cool the house off at night for sleeping and then program it to warm the place up in the morning, it is possible to create venting and pressure issues.  My own place for example, from time to time I shut down the boiler at 6 am to do service on the system.  Once the service is done I turn it back on at say 6 pm, and all hell breaks loose.  Good way to find all your leaks.  Anyway, just a suggestion, eliminate, or reduce, the night-time setback

crash2009

setback, pressure, venting

I just wanted to add, that adjusting the setback just buys you some time.  It sounds like you have a pressure problem also, and it never hurts to review your venting strategy.

nicholas bonham-carter

2 sides of the same coin

actually i think that ed and i are on the same page.

the best practice is to fill the mains completely at almost no back-pressure or resistance; and when the main vents close, then the steam pressure [whether 2 ounces, or 2 psi] will push on the air in all the risers equally.

if you had the opposite setup [slow main vents and fast radiator vents], then the air will be pushed up the nearest riser with a big radiator vent first, and next the 2nd nearest with a slower vent, and so on. the result will be uneven "steam arrival", and the only cure is bigger main vents, and slower radiator vents. if the thermostat is located near the nearest big-vented radiator, the rest of the house will be colder, because they are getting late steam.

later on, some fine-tuning can be done to increase the radiator venting in areas served by longer risers or runouts. plates of butter pats placed on the radiators should all melt at the same time.

having low-pressure will serve better to get the steam to each floor simultaneously, and lower the fuel consumption.--nbc

malex

Nightly setback

I have the tstat set to 64 at night and I have yet to hear the boiler kick in during that time (we blew in insulation on all exterior walls this spring after we bought the place so it keeps the heat pretty well). I will raise it up a bit for the night and see what happens and hurry with insulating the mains so that per Eds theory, there will be less condensation on start up.



Crash - what pressure problem are you referring to? The fact that it goes just past 2psi before shutting off. Is that attributable to something else than a not very accurate pressuretrol?

Long Beach Ed

Slower

Your problem is that some part of the system isn't handling the condensate being made on a cold day or morning.  Your goal would be to either reduce the condensate going through that bottleneck or slow the stem velocity through that area if it were a counterflow pipe.  In theory, insulation would help as it would reduce condensation.



It doesn't matter if we're talking about a main, a raiser or a runout.  If the pipe can't handle the condensate, you have to give it less and the easiest way to do that is to slow the steam in that area. 



Most commonly, the problem lies in either an undersized runout to a radiator or a lack of pitch on the runout.  It could even be a backpitched radiator. 



Of course the problem could be in a main too, if it has poor pitch, is undersized or has a sag in it. 

crash2009

Pressure

I was just referring to the pressuretrol allowing more than 2psi.  I am just going from memory, and it was a year ago, but one of the reasons I went to the vaporstat was to save my vents.  I think it was about 1.4 psi that the Gorton 2's started hissing a lot.  I believe this hissing causes them to have to be cleaned more often.  Maybe that's true for all the vents, radiators too.  I think vents will last longer if you keep the pressure down in the ounces range rather than pounds.



Setback or not has a divided following here.  I subscribe to one temperature all the time.  In fact I put a lock box on the thermostat.  Mine has been at 70 F since forever, with the exception of troubleshooting.

Mark N

Set Back

It is my understanding that using set backs with a steam system can be problematic. I myself don't use one. If you are going to use one don't make it more than 2 degrees. Now on to other things. How many rads do you have and what is the total EDR of your system?

What size boiler do you have? I would think that if the gorton#2 isn't getting hot that it may be stuck closed. Take it out and check it. Is your pressure really getting as high as 2 PSI?

A small system such as yours should run at only a few ounces of pressure. Mine regularly runs at 1 ounce or less. If you are up at 2 psi I would think that your boiler is most likely oversized. The pressure being to high can cause hissing vents, condensate not to drain, high fuel consumption.

Steamhead

It's pretty much impossible

to vent a parallel-flow main too fast. As long as the main is pitched properly and the return isn't plugged, the condensate won't build up in it.



It may be possible to vent a counterflow main too fast, since the condensate may not be able to drain back against the steam. But I have yet to see this happen.



It is definitely possible to vent a one-pipe radiator too fast. This happens all the time.



Also check for missing pipe insulation. This means you will generate more condensate.

malex

Vents quiet this morning

Of course it is much milder today but I raised the set back to 66 so that the system is not dead cold when it starts up.



I am taking final measurements for the insulation and will put 1 inch on all mains and run outs. One of the problem radiators that has a riser on the north facing wall actually shares a wall with the garage so I will break through the garage wall to make sure the riser is insulated all the way up to the radiator.



I'm also considering getting a vapor stat so that I can do the fine tuning a la Ed and NBC. I read some posts about sucky Honeywell vapor stats so does anyone have a recomendation what to get. Do you need to consider any system parameters?



Thanks everyone for good input - now I have to turn into good output.

BobC

two stage temperature raise

Depending on the type of thermostat you have and the schedule for temperature changes, you might be able to raise the temperature in stages. I go from 60 to 63 at 7am and then up to 65 at 4pm. That might tide things over while you deal with the venting issues.



i also have a vaporstat and my cutout is set at 12oz with a 4oz cut in.



Bob 

Long Beach Ed

Vaporstat

A vaporstat's not necessary, but in a case where a boiler is oversized and continually builds pressure in the system, it can save you a few bucks.  Beware that in many installations they never pay for themselves, which is how we measure their worth.



If you want one, try to find an older one with a mercury switch.  The newer ones use a snap switch and we've seen several that fail to cut out at all.

crash2009

2 Stage warm up

Thats a great idea Bob.  Then Malex could have the best of both worlds.  Don't know if you need it or not but here it is.  I collected a whole pile of insulation info from both on and off the wall.  My entire insulation file is posted here  http://www.heatinghelp.com/forum-thread/137178/Insulation    Re-vaporstat.  There is a lot of different models, and they all look the same.  I have the Honeywell L408J1009.  It is a 0-16 oz.  Out of the box, it was set to off at 8 oz and back on at 5 oz.  According to my gauge it's actually off at 8 oz and back on at 3 oz.  Thats where I left it.  It has worked flawlessly for me.  My suggestion is: Get a good gauge and get good at reading it, then get a vaporstat later if you need it.

BobC

It all helps

I insulated all the piping in the basement and installed a NOS mercury vaporstat the same year. In my particular case it saved me about 20%. That vaporstat is the 0-4lb model and I don't know if it will go much lower than the 12oz cutout (4oz cut in) it's set for right now.



When the Burnham v75 comes out you can bet that vaporstat will be put on whatever boiler i get to replace it along with a low pressure gauge. I'll use the stock pressuretrol as a safety backup.



That insulation package you put together is a great resource for anyone thinking about saving some fuel!



Bob

malex

Crash course in insulation

I read your thread on insulation already several times. Very helpful. Doubt that mine will look as good when Im done. Before I put it up I have to make sure the pitch everywhere is good. Because the long main is counterflow in the first half and parallel flow in the second half I have some particular challenges. The first stretch of parallel flow is pitched the wrong way slightly. There are no rads here so there shouldn't be much condensate but still must fix it before insulation goes up. Changing the pitch on 2" black pipe is easier said then done.



Will probably hold off on the vapor stat until insulation is up. Curious to know how I should install it. I currently have the pressuretrol on a T with the low pressure gauge. If I want to keep the pressuretrol as back up do I build a T on the first T or do I extend the first T?

crash2009

Picture

How about a picture of the mains.  Maybe someone might have a good suggestion for you.

malex

Main pictures

1. Main comes off the header

2. Main makes a 45 to get over the beam

3. End of main dips (I have since put a hanger towards the end)

crash2009

No Takers Huh?

Might have to start a new thread, and repost the pics.

Steamhead

In the second pic

where the main 45s over the beam, is the steam moving toward the beam or away from it? And does the pipe slope away from the beam, or towards it?

jpf321

2 small comments ....

1) This is one of the reasons why I advocate NO or VERY SMALL SETBACKS .. this decreases the early morning cold equipment syndrome. The equipment stays pretty evenly tempered 24/7.



2) Increasing the pitch in a PARALLEL-FLOW situation may help, but in a counter-flow this may hurt -- especially when that big glug of water hits its first elbow. Increasing the pipe size in either would probably help. Installing a drip to a wet return is always going to be helpful, but not always practical

ttekushan_3

It may be worth

revisiting this thread:



http://www.heatinghelp.com/forum-thread/138703/Gorton-Vents-venting-slowly

jpf321

no wrong way....

as long as it's a HUMP rather than a SAG, there's no wrong way to pitch. the water will find its way back either through header/equalizer or by dry/wet return. don't go trying to fix what ain't broke.



as I mentioned way above before I read down this far. reduce your nightly setback .. since you say you've insulated, then running constant temp should not be an issue. did you ever time how long it takes to recover temp in the morning vs. how often the boiler runs at night to maintain temp .. I have :-) The recovery loses just about every time.



Keeping pressure low will do several things not just save fuel during fire-off times ..

1) reduces large system water level fluctuations/differentials

2) quiets hissing (either outbound air or vacuum sucking) vents.

3) saves fuel

4) less stress on the vents (some are only rated to 3psi. (Hoffman 1A's?))

5) saves inlet valve packing/hissing

6) speeds steam delivery (not really since all steam movement starts at 0.001 pressure)



All that being said, I run/ran at about 9oz with a 2oz diff... and with

a) constant temp 24/7 and

b) a properly sized boiler

c) with balanced system and

d) a well placed t-stat,

.....the t-stat will almost always (except for design day and its close neighbors) drop the call before I hit 9oz. Usually I hit pressure at about 35mins-45mins of fire.



When I ran testing with nightly setbacks .. I almost always hit/cycled on pressure during the last 3rd of the t-stat call.



These days, with my eTRVs I sometimes only make steam for 1,2,3 rads of 15 total at a time, especially at night/weekends when my steam is 2nd stage heating in most rooms.. so I thank my lucky stars for my Honeywell L408J1009 vaporstat. Since I fill em pretty quickly. But I also don't care since I then cycle comfortably on my v-stat. I also have a digital pressure transducer .. but it's their more for it's large LED readout and is NOT hooked into the system.

malex

Point well taken

But im not sure I will test the theory by staying up and checking nightly run time :-)



Given that I have the pressuretrol set to min .5psi and diff=1 and it is still not cutting out until 2+psi my only option would be to get a new one or upgrade to a vapor stat, correct? Any system will eventually have the pressure rise and the pressuretrol is the only thing that gets the system to take break and let the pressure subside before going again.

jpf321

have a look over...

here ... http://www.heatinghelp.com/forum-thread/139075/Correcting-pitch-before-insulating/success

MrDvorak

Temperature recorder

Technology stays up for you the whole night long: http://www.amazon.com/Lascar-EL-USB-TC-LCD-temperature-readings-thermocouple/dp/B003DRSFAO

If you record a temperature of the smoke pipe with this thing, you can get high precision measurements your boiler burn time.

jpf321

exactly .. couldn't have said it better ...

You may want to glance over this thread .. and have a look at my screenshots ..

http://www.heatinghelp.com/forum-thread/132987/let-the-data-begin