Single pipe issues

Fizz

Just closed on daughters house which has single pipe system. Some rads slow to heat. The system has 2 mains from boiler with 4 rads on each. The front has attached radiation of 126, rear 95. The system has separate return for each main, vented at boiler by #1 Gortons on each. The left Gorton is slow to vent. Tried removing using regular wrench with no success. Want to increase venting there. Boiler is 1988 WM SGO3, believe 356 SF, attached rad is 221SF. Replaced 2 rad vents; one was shot, the other too small. Most are Maid O Mist, but one I found interesting was a Homeart air valve with siphon. See Pix. Boiler hasn't been serviced in 2 yrs(oil), site glass leak, dirty, and think pigtail either blocked or not registering because steam doesn't get to left vent til near end of cycle. Any ideas?
Fizz

neilc

can we get a pic from the right side, diagonal from paneled wall, showing the pipes out of and over the boiler? also from same position a diagonal of Ptrol, gage, and pigtail?
let's see a picture where the condensate returns to the boiler
Is the Ptrol turned down as low as It can go?
check with the cover off, don't let the nut drop off the bottom of the adjustment screw.
is the white wheel inside set to 1? (1 facing forward)
too much pressure can foul your vents.
what pressure do you see on the gage?
get your main venting working well, fast and somewhat timed evenly, first,
then balance or replace where needed the rad venting.
you know to blow down the low water cutoff, right?
in your last pic, is that coupling leaking? wood wet and stained?
other leaks??

Fred

You probably already know that the boiler is not piped correctly. No Header, doesn't look like there is an equalizer (I do see a pipe drop down in the middle of your first picture. Maybe that is suppose to act like an equalizer but, if so, it still isn't located where it can be effective. I don't see a pigtail on the Pressuretrol. It looks like just a couple nipples and an elbow/Tee. Can't see the scale very well but it looks like the Cut-in is set high. Set it at .5 PSI and make sure the white wheel inside is set to "1". Also, it looks like the LWCO blow down valve is open. Is it? If it is open and no water comes out, that's a real issue. It's an almost 30 year old boiler. Well over-sized as well. Probably not a good investment to spend much money to pipe it correctly until it's time to replace it. I'd have it serviced, especially since it is oil. It definitely needs to be drained and flushed out. It probably does need larger main vents. How long is each main?

Fizz

Ea picture can be clicked-on, then enlarged. The pipe drop in 1st picture is actually 2nd riser off drop-header. Cut-in on P-trol is at .5, didn't ck cut-out. Pressure on gauge(30oz) registered 1-2 oz at end of cycle, otherwise 0. Because the house had been vacant for 2 yrs(estate thing), I've blown-down several times in each of last few days to get water pretty clear. The LWCO lever is in reversed position-up is blow-down, down is close. The gauge and p-trol are actually connected to same pigtail. The mains are about 28' on left and 22 on rt. Yes, Neil that is leak on return, only one if found so far on piping. You may note that picture of rad supply valve has wet spot on carpet I saw this AM. Yes, boiler is oversized. Scheduled for service this coming wk, tho cold weather may push-it back. Thanks for feedback!

Fred

What are you calling a Drop Header? I don't see a header at all but maybe a picture from a different angle may show a header running from front to back of the boiler?? If so, then maybe the pipe I was referring to is actually an equalizer.

Fizz

Hope these help.

Fizz

Addendum to prior comment on length of mains. The left main is 34', rt is 28'. Now the drip on each is 30' and 25' respectively; being that steam must fill these would that be added to main. If so a total of 117' of piping which would add how much to requied steam capaciy?

BobC

Is there any signs of panting on the slow to heat radiators? If so it could indicate some water pooling in a pipe and quenching the steam. Check the slow main with a level to make sure it has some slope to it so water can find it's way back to the boiler. Also make sure there aren't any dips along the main.

Bob

Fred

These pics help a lot. Not a Drop header but there is a Header there! I would put a Barnes and Jones Bigmouth on each of those returns. It doesn't add anything to the required steam capacity but, because the vents are at the end of those returns, it does add some additional venting capacity as the steam will continue down those returns until it closes the vents and before it actually begins to fill the radiator run-outs/radiators. One Bigmouth on each return should work fine though.

neilc

That first head on boiler picture was a little deceiving, hiding
things we all like to see, doesn't look as bad now,
I think Fred and I saw all those 22s and 45 couplings and got lost.
Too bad the riser is reduced from the boiler, and the header could have / should be larger still, but better than what the 1st pic shows.
Get a bigger wrench, some penetrating oil, and a pipe wrench to back up the nipple the vents are on and get those main vents venting, being brass and dissimilar they should come out fairly easy, use some tape for the next time.
If the nipples do move it might be easier to take them out and loosen the vent on a bench or vice.
Get after the leaks too.
Then insulate all the steam carrying lines down there.

Fizz

Thanks guys, good advice.

Fizz

Just measured main pipes size: left is 11/2", right 2", which could account for difference in heating. Was able to remove left vent nipple, but due to weather(24" snow), haven't been able to get to it.

Fizz

Put Gortont#2 on front return, no difference. Back return with #1 vent much quicker. Noticed last leg of return from 90 degree elbow to vent is level and few straps off. Could this be reason for venting issue?

Fred

If that level return is holding enough water, it could be blocking air from venting. Can you feel air venting from the Gorton when the boiler starts to make steam? Does the vent close on steam?

Fizz

I just installed today, and not much air coming-out. Prior vent(Gorton#1), never got to close on steam because it was so slow in venting. Other side vents fairly quickly and closes on steam.

Fred

I would say that level dry return is probably holding enough water that it is condensing the steam before it can get to the vent.

Fizz

Just got boiler cleaned, serviced, new pigtail, site glass. Stove pipe half-blocked, with plenty of crud on boiler walls and pigtail, plus nozzle which we replaced. Boiler operating at 82% eff, 2oz pressure. Dry return in ? got warm to vent, so Fred you are probably correct; issue could be resolving. We'll see in next few days, as tom is going to be cold hi 30, low 14. Holding-off on pipe leak til off-season. Thanks for feed-back.

Fred

Let's hope all runs well.

Fizz

Well, front main return still very slow with some rads not heating. Yesterday I ran system for 30", return got to vent and rads all heated. Left t-stat at setting from yesterday, returned and same issue. Thinking it should have resolved if by now.

Jamie Hall

If the main is properly sloped, and the runouts are properly sloped, and the main still is slow and some radiators aren't heating... it pretty well has to be a venting problem.

Fred

What kind of vents do you have on the rads that aren't heating? Is the pipe below the valve on those rads hot? Are they the furthest from the boiler? Are those rads on the return that is level? Did you re-pitch that return?

Dave0176

Fizz said:

Yes, boiler is oversized.

The boiler isn't exactly oversized. It's an SGO-3 the smallest oil fired steam boiler Weil McLain makes. That boiler can be fired quite a bit lower. I'd size the EDR properly then select the nozzle that suits both the steam side and the hot water.

As far as Gorton vents go, I've had nothing but bad luck lately with them, mostly as they don't seem to want to close when hot. So I've been using Maid O Mist. I won't buy nothing Gorton no more, got tired of the call backs including the No-1 main vents. For main vents I use Barnes $ Jones.

Fizz

Jamie, agree, that's why I replaced a Gorton#1, with #2 on slow side. Didn't help. Fred, have M O M's#6; pipe below rad's in question only get hot after system has been running about 15", and then rads get hot after return gets hot about 2/3. Two of rads on 2nd fl, other is at end of run. All rads on this side are seviced by same main and return which was properly pitch til last 90 degree run that was level. I have repitched it. The other side set-up for main and return is identical, but only rad is on 2nd floor. 3 of 4 heat very well and quickly, but nearest one on 1st fl is slow(valve is seized, don't know if fully open. Dave, both sides are steam; and boiler just serviced with .85 nozzle. EDR is noted in first comment.

Dave0176

Fizz said:

Dave, both sides are steam; and boiler just serviced with .85 nozzle. EDR is noted in first comment.

On one of those pics I see a domestic Hot Water coil.

Fizz

Correct, that's what you were referring. My aplogies.

Dave0176

A lot also depends on the pressure they set the pump to. If you set the pump to 140 psi and use a 100 psi .85 nozzle it'll acts like a one gallon nozzle. Typically 1 gallon inputs about 140,000 btu and .85 puts out about 119,000 btu. I'd run a .75 nozzle which will get you to 105,000 btu, or if your pump is set to 140 you can run a .65. Hope this all helps.

Fizz

It does. The # after nozzle is 70, assume that's pump psi? The system has been running at 1-2oz.

Fred

How high is the water in that sight glass? I see in one of your pictures the McDonnell Miller #67 LWCO is mounted a couple inches above the bottom of the sight glass connection. They are typically mounted on a Tee on the bottom of that sight glass. That LWCO has a float in it that will drop and call for water when the boiler level get down to the very top line cast into the side of the LWCO housing (and that is a low water call) If it fills much more than that, there may not be enough room in the top of the boiler (steam chest) to make steam.

Fizz

Water is not quite 1/2 way. There is no automatic feed, and I haven't had to add.

Fred

Have you stood by the boiler for a full heating cycle? With the LWCO mounted where it is (at least the way it looks in the picture) It is possible the boiler is shutting down on a perception of low water and waiting for enough condensate to return to re-fire the boiler. If that is happening, you simply are not generating enough steam for a long enough period to allow it to move through the entire system. Is the thermostat being satisfied? If so, is it in a room nearest the boiler? Raise the water level to about 2/3's of the sight glass and see if that makes any difference.

Fizz

No, I haven't stood next to boiler, but I have been in room above where t-stat is which is also nearest to boiler for a complete cycle with t-stat satisfied. Yesterday I was there for a 30 min run with no shut down. The issue in my view is a smaller supply line(11/2") on front side vs 2" on back, or the front return is possibly blocked.

Fred

@Fizz , rereading one of your earlier posts, I think the problem may well be the fact that you are using M-O-M #6 radiator vents. They vent fast, at about .15 CFM and the nearest radiators are probably stealing all the steam before it can get to the radiators that don't heat. That M-O-M vents at twice the rate of a Ventrite set at its highest setting of "8" and a little faster than a a Hoffman 1A at its fastest setting of #6. Try a few ventrite #1 adjustable vents so you can tune them down to around #5 or #6 or a few Hoffman 1A's set at 3 or 4. I suspect that will resolve this issue.
http://www.hvacrsupplynow.com/VENT-RITE-1-STEAM-AIR-VALVES-ADJUSTABLE_p_1787.html

Fizz

Actually, 6's are on slower rads, have 5's on 4 others, and 2 varivents at half setting on 2 of faster rads. Perhaps Hoffman 1A. How about MOM 3 or 4's?

Fred

M-O-M 5's are better at .10 CFM @ 1 ounce of pressure, .20 CPM @ 3 ounces. and Varivents at 50% setting, are way too fast @ .34 CFM @ 1 ounce and .76 CFM @ 3 ounces @ 50% setting. Put the Varivents on minimum setting and see if that helps the other rads or switch the varivents to the rads that don't heat and see if they get good and hot while others remain cooler. That will pretty much tell you it's a balancing issue.

Fizz

That's good info, Fred. I picked-up 2 #4's to put-on quick heating rads. I put the #4's on back side rads that heated quickest, and they did reduce steam to them, but they had no effect on front side rads which I put #6 and D on. Steam is still slow moving.

Fred

Let's start over here. Are you 100% sure all the mains, dry returns and run-outs to those slow rads properly pitched? Are the slow/no heat rads all on the same main? Are you sure the main vents actually are open until steam hits them? Are you 100% sure the incoming gas pressure to the boiler is correct? There is something else going on here and I'm inclined to suspect the gas supply from the utility company may not be correct.

ChrisJ

Fred said:

Let's start over here. Are you 100% sure all the mains, dry returns and run-outs to those slow rads properly pitched? Are the slow/no heat rads all on the same main? Are you sure the main vents actually are open until steam hits them? Are you 100% sure the incoming gas pressure to the boiler is correct? There is something else going on here and I'm inclined to suspect the gas supply from the utility company may

It's an oil burner Fred.


@Fizz
Can you draw us a crude map of the piping, the lengths and size of the piping, and the size of the radiators?

Sort of like this, but I changed and improved this many times over the years. Spend 30 minutes or so doing it, it doesn't have to be perfect. If easier, draw it on a piece of paper and take a picture of it.

Fred

@ChrisJ said: It's an oil burner Fred.
After all this time, I should have looked at the pics again but I didn't. In any case, the fuel supply has to be right, oil or gas. and that needs to be checked.

ChrisJ

Fred said:

@ChrisJ said: It's an oil burner Fred.
After all this time, I should have looked at the pics again but I didn't. In any case, the fuel supply has to be right, oil or gas. and that needs to be checked.

Maybe.

Maybe not.

Fizz

Crude drawing attached. Hope it helps.

Fizz

last oil pump PSI 140.