Another skimming question

Emeliza

My new boiler is installed, a Burnham Megsteam 629. I have 2 antlers of three #2 Gortons on each main. The installer did the initial skim when he installed the boiler a few weeks back and he was here today to do another skim (which amounted to filling a five gallon bucket a couple of times until the water ran clear) and put the vents in. I have new air vents on all the radiators. #1A Hoffman's. The downstairs radiators are heating up and two of the upstairs ones are heating up. But two of the 2nd floor radiators on one main and the one radiator on the other main are still stone cold. I still see crud in the sight glass which means I probably need to skim again. I watched Gerry Gill's video on skimming and I understand what to do, sort of. The only thing is that my system is set up with an automatic water feeder, and I am not sure if there is a manual feeder like I saw Gerry use in his video. I am not exactly sure how I should proceed with the skimming.

KC_Jones

There should be a manual feed valve and isolation valves for the water feeder. If you post a couple pictures of the water feeder and it's associated piping that would help.

Emeliza

Okay. Here are some pictures of boiler, piping, water piping and vents. My insulation job isn't as slick as Gerry's but it does the job--when I finish it, that is; a little bit more to do on the near boiler piping and in the crawl space under the kitchen.

KC_Jones

You are correct I don't see a manual feed. That makes me wonder how the contractor skimmed it? How long did they spend skimming. Times vary, but to fill a 5 gallons bucket skimming is probably 1-2 hours. You really should have a manual feed. The only way (and I don't recommend it) would be to throttle the ball valve at the end of the feed pipe and hold the manual feed on the water feeder. I doubt that is good for the feeder or your finger. You really need to get a manual feed installed. In the manual for the feeder there are actually installation instructions showing this (see link).
http://www.hydrolevel.com/new/pages/pdf_files/ModelVXT24Instructions.pdf

Emeliza

He definitely not spend 1-2 hours skimming it today. I thought he ran the water too fast. He skimmed for an hour or so right after he installed it, put a compound in the water to make the oil stick together, I guess and then skimmed that off. What I have been doing today, is heating up the water (when the sight glass water is turgid and gunky looking and the heat goes off I run water into the bucket from the skim tap (it comes out really dirty) until it runs clear, then turn the tap off, empty the bucket, wait a bit for the water to fill back up or it the feed button, then heat the water back up again. I think doing it this way will take forever!

KC_Jones

Have you seen video of skimming? @ChrisJ can you post a link to that short clip of you skimming?

Emeliza

I did see Gerry Gill's video but would love to see another. The system is on right now and the radiator in the family room, it's downstairs at the end of the line (whomever put this radiator in way back when piped the run in copper, not good but I can't change it until spring. I have a wood stove in this room so I'm good for this winter. But the reason I mention this is it started to bang and rattle before starting to heat up which it is now doing quite nicely. I've got the heat cranked up to see if I can get all the radiators producing heat. What a way to spend a day off!

Oh, and the boiler is still short cycling, coming on for no more than five minutes then going off. (There is heat in the entire radiator now, a 6 tube-17 section one).

Emeliza

I just checked all the radiators and they all have heat, but then again I had the thermostat cranked to 80 just to see if I could get them all fired up. I'll dial the thermometer back down to 66 or so, where it is a little more comfortable, and then see how that keeps the heat coming.

Emeliza

Got another problem. The radiator we took down from the attic and installed back in the room it came out of is leaking at the air vent end, not the valve end. I noticed a stream of water going across the floor and thought the dog had decided he couldn't wait. But no, I towled it up and felt the bottom of the radiator for water, sure enough, water. So this means I should look to the salvage yards to find another radiator. But how do I know that the salvaged one doesn't leak too? Is there any way of testing or is the only test is to install it and see if it works?

KC_Jones

Another question, are you skimming through that red handled valve above the bucket in your picture? If so that is not the skim tapping on that boiler according to the manual it is the indirect water heater supply connection. The skim tapping is inside the large "knock out" above and to the left from where that pipe is. It looks like it was left plugged and never hooked up. The boiler does not come with fittings for this it's up to the contractor to put a pipe and valve or plug/cap, basically something to make it useable. And like I said without a manual water feed valve it really can't be properly skimmed anyway. I mentioned 1-2 hours for a 5 gallon bucket. On a new installation I wouldn't expect 1 bucket to do it. I have over 10 hours of skim time on mine so far and I am doing it one more time this weekend. I replaced a lot of piping on my install though so the amount of skimming can vary. You will hear this many times on this site, there is no replacement (chemicals or otherwise) for good skimming. Think of it this way imagine trying to get just the oil out of a bottle of salad dressing. If you pour really really slowly you get just the oil off the top. If you suddenly dump it upside down you just mix it all up. It needs to be slow.

Emeliza

Yeah, that's what I figured. The place where the red handled valve and the pail is where I have been letting the water out of. The water that is coming out is really dirty and murky. I let it dribble out until it runs clear then shut it off, wait for awhile, then let some more water out. I think this is the only way to do it since that large knockout is plugged. The piping I had replaced was all the near boiler piping and a small section of one of the mains. The sight glass is looking a little clearer below the line of crud that is sticking to it but the water line still bounces a bit when the burner comes on. As for the leaky radiator, I am going to try to find one for a single pipe system at an architectural salvage yard, one that will put me right at or just under the 629 SF EDR that my boiler is rated.

Robert O'Connor_12

why not use a clothes washing machine type hose? Hook one end to the drain on boiler and the other end to a water source? fill it real slow though or hook up something you can regulate it with. Just don't leave it hooked up. It's technically a cross connection but will solve your feed issue for skimming temporarily.

KC_Jones

Or they could get the contractor to correct their install error. The water feed just isn't correct in any way shape or form. This is a brand new boiler correct? In addition I would have them put the correct skim port in, but that's just my opinion.

Emeliza

About using the washing machine hoses, is the boiler drain down at the bottom (the mud leg?)--see picture 2293 in the vicinity of the bucket? Do I attach it there and feed the water in very slowly while I skim from the red handled valve above (looks like the installer put the nipple and valve in the spot where the indirect water heater would go "K" according to my manual. The surface blowoff is labeled "J" (Fig. 7 p. 16). "K" is no more than 3 inches lower than "J". Heat water up, turn boiler off, hook up hoses (one to feed water into bottom of boiler, the other hose to drain to my sump). Of course I'd be watching it the whole time, babysitting it while doing other cellar projects. Does this sound right?

BobC

You can feed water through that low drain tad but I would drain water out of that tap till it's reasonably clear before feeding water into it; no sense in stirring up the mud.

As to using the upper tap to skim from, that is not going to work, you need a larger straight pipe to do effective skimming. Also that small port is too low, the oils on the side of the boiler will still be there no matter how many times you skim. Get someone in to install a pipe and full port ball valve in the skim port. When you skim do it slowly, it should take at least 2 hours to fill a 5 gallon bucket. Also have them install a valve so you can bypass the auto fill and a valve so you can shut the autofeeder off.

Autofeeders are responsible for a lot of premature boiler failures because the owners don't pay attention to how often they are feeding water. Your best off valving them off unless your going to be away from the house for several days, then you will be aware of water use and you will be prodded to find out WHY it's using water.

Bob

vaporvac

Here's an old link of mine that references a couple of great posts concerning skimming technique. While they don't address your current problem, they may come in handy when you have a proper skim port.
http://forum.heatinghelp.com/discussion/148579/proper-skimming-technique-the-details#latest

Emeliza

I just looked up the directions in my manual concerning initial operation of boiler and skimming. Here's what it says:

"Operate the boiler with steam in the entire
system for a few days allowing the condensate
to return to the boiler. If the condensate can
temporarily be wasted, operate boiler only for
the length of time it takes for condensate to run
clear. If the latter cannot be achieved or if the
condensate is returned to the boiler, boil out
the boiler using the SURFACE BLOW-OFF (this is where I should install the skim port)
connection, see Figure 7.
i. Drain boiler until 1” of water is visible in
gauge glass. Run temporary 1½” NPT pipe
line from the surface blow-off connection to
an open drain or some other location where
hot water may be discharged safely. Do not
install valve in this line."

So, if I have my installer put in a port like Bob showed in a previous comment, will that void my warranty. Technically I am doing something the manual says I should not do. There is a lot more in the instructions.

I tried the link for proper skimming techniques and got a "page not found" message.

Emeliza

I tried the other post from VickiS and that article on skimming also could not be found. I anyone has it in PDF form could you attach it to a comment? Thanks!

KC_Jones

I doubt you have issues if you have a valve installed it's done all the time by the pros on here. If you are worried you could just do a cap or a coupling with a plug, but if you do that I would suggest using a brass plug or cap. That way if you need to open it up later it won't be so hard to open up again. The brass tends to not seize up with corrosion like steel can. With the valve (already brass) that is automatically taken care of. I would add if you do go the valve route still put a plug in it when you are done skimming it's a good safety so you aren't depending on the valve entirely. If I had to guess this could be why Burnham says no valve, but I am just guessing.

BobC

I agree the skim port should be capped even if it does have a valve on it. My installer put the skim port and valve on as I asked, I was leery about someone opening that valve when the boiler was steaming. If you look at the picture of my Smith boiler that I posted above you will see a threaded brass plug that I put in when I'm done skimming.

Bob

KC_Jones

BobC said:

I agree the skim port should be capped even if it does have a valve on it. My installer put the skim port and valve on as I asked, I was leery about someone opening that valve when the boiler was steaming. If you look at the picture of my Smith boiler that I posted above you will see a threaded brass plug that I put in when I'm done skimming.

Bob

I have seen stupid things like this done with uncapped valves before...it never ends well. Wait no don't.....and then the mess comes. As you say under full steam it becomes a safety issue then. My sister worked in a seafood place one summer. She didn't understand how to tell if a ball valve was open or closed (why they never trained her is beyond me). So the timer went off on some shrimp and someone else closed the valve and she didn't realized. She walked over and instinctively closed (really opened) the steam valve. She opened the steamer door and burned herself badly. It wasn't pretty. Luckily it was only her wrist and hand. All valves should be respected and understood. Sorry off topic a bit.

Emeliza

So, the suggestion is to install a 1-1/2" full port valve and plug (threaded, I presume) and a 1-1/2" nipple. Would a 6" long nipple be long enough for a skim port? I could buy it at my local plumbing supply store and have it on hand for the installer (when I can get him). And, of course have him add a manual over-ride to the automatic water feed. I probably need to do this before it gets really cold, right? Or can I let it wait until later. I do have a drop header that is larger than the risers and I had the installer eliminate the bullheaded tee. The system is running and the house is reasonably warm.

BTW, the pipe and valve that is currently installed is at the normal water line (matches up with the line in the sight glass) and every time I open it up to drain it into the pail it comes out black and dirty. Since this pipe is right in line with the normal waterline, am I getting off some of that oil?

To reiterate, you are saying that the skim port needs to be larger diameter and above the normal water line and I need to manually fill the tank to that level, heat it up to almost boiling, turn the boiler off, then start my slow skim and slow water feed for 4-5 hours and repeat as necessary or until water comes out clear. Right?

Sorry if I keep belaboring the point, but I don't want to do something that will screw my boiler up and I want to be able to explain to my installer (who seems to know steam pretty well but I think there are gaps in his knowledge) why I am asking him to do whatever it is that I am asking him to do.

Fred

Yes, a 6 inch nipple is long enough and the pulg sould be treaded (Brass plug). You do want to use a nipple the full diameter of the port and a full port ball valve the same diameter. It doesn't need to be done before the weather gets cold but the sooner the better. It can be done anytime between boiler cycles as long as you are sure the steam has subsided. That port is above the water line so there is no need to drain any water to install the skim port. I heat my boiler first, then add water to bring it up to the skim port and let it trickle for several hours. If you fill the boiler up to that port and then run a heat cycle you may get some banging as your water level will be so close to the risers that it will probably suck some water into the header. Not a huge problem but somewhat un-nerving. I suppose if you can just get the water to almost a boil, but not steaming, that will work fine. Im not sure why he put that valve (with the red handle) at that spot. If it is at the normal water level, it serves no real purpose unless he intended that to be used as your skim port which isn't an ideal setup for skimming. You may want to ask him why its there and when he puts the proper skim port in, maybe he can remove and plug that tapping. No need to have a useless valve there that will eventually leak/need washers installed. You may be removing some of the dirty water whan you open that but at this point you are depending on your auto water feeded to refill the boiler and that simply doesn't lend itself to skimming. You need a manual bypass that you can throttle down to a very slow trickle.

Emeliza

I think that valve is there to blow down the system once a week. Or is that not something I have to do? Is the reason why the boiler comes on for 5 minutes or so, goes off and then maybe 10 minutes later comes back on again because it is not really cold enough yet to go for any longer as the thermostat is satisfied. Is this short cycling still (thought that would be cured once I put the new air vents in--3 #2 Gorton's on each main?

Fred

The blow down valve is on the bottom of the boiler, not at the water line. That looks like it by the bucket in the picture. What type Thermostat do you have? Is it set up for steam at 1 CPH (cycle per hour)? If there is a lot of bounce in the water level (oil) that could be shutting the boiler down prematurely and the burner probably has a delay on it. That won't go away until you skim and skim and skim. It's not because the Thermostat is satisfied or it wouldn't come back on in 10 minutes especially if the thermostat is set up right. Check the thermostat programing and if thats correct, wait till you skim to see if that resolves the problem.

Emeliza

My thermostat is an old Honeywell, round, probably from the 70's and here when I bought the house. So I should probably buy a new one that I can set up for steam. Got any suggestions?

And I'll check to see if the waterline is bouncing when the boiler comes on. (I'm following all your suggestions for getting a good skim port installed--maybe my regular plumber, who I need to come out and fix the tub, can install it and put on a manual valve to override the automatic water feeder. Or should I have the original installer do it just to be consistent? He's the one I call to clean my system once a year.

The only time the boiler stays on for longer than five minutes is when I have the thermostat kicked up to 75, that's also when I notice that all the radiators in the house come on.

KC_Jones

I have never messed with one, but those old round ones should have a device called an anticipator. This device basically makes the thermostat think it's satisfied ahead of time because steam systems have so much mass they will continue heating even after the thermostat is satisfied. I am of course assuming yours has this device. It would be good if someone more knowledgeable on the topic chimed in. I don't think you need to change the thermostat unless that is you want a new digital one. If you do a search on the wall you will probably come across some more information about it.

Fred

The old round ones do have an anticipator but that is different than controlling the number of cycles and you can only anticipate within a limited range. I switched my old round one out for a Honeywell RTH-7000 series but any programable thermostat that allows you to program for steam/number of cycles per hour is usable. Most will say that on the packaging. It just depends on how many other bells and whistles you want to add beyond that.

SWEI

If that's an original T87 with a mercury bulb and it's working, the anticipator should work just fine if it's properly adjusted http://www.inspectapedia.com/heat/Heat_Anticipator_Operation.htm

Fred

With what SWEI just said (and the fact it worked with your old boiler) , I think I would leave that thermostat alone for the time being until you get the skimming done. I suspect the boiler is shutting down because the water level is bouncing enough to cause the LWCO to think it is low on water and the burner has a delay on it before re-firing and that it refires in 10 minutes because the Thermostat was never satisfied (given the setting on the anticipator).

Emeliza

I haven't been able to get the installer out to put in the proper skim port or a bypass valve so that I can manually adjust the automatic water feeder-- that said, I haven't skimmed it correctly. To me the sight glass looks like there is all sorts of swimming brownish oily particulates and some are glommed onto the upper part of the glass. Could my not having it properly skimmed be the cause of the way the new boiler is running? I have the thermostat set at about 65F. I went downstairs and timed how long the boiler ran (2.5 minutes) and how long it was off (6.5 minutes). Only approximate as I have no time piece with a second hand . So I guess that means that in an hours time the boiler cycles roughly 6 times (6x9=54 with 6 minutes left over). I started counting when the boiler went off. It's not that cold out right now (29 or 30 F) and the house feels okay (I like it on the cool side because I have a wood stove in the family room. The thermostat is on the wall between the kitchen (which is the room adjacent to the family room) and the dining room and the radiators in the kitchen feel warm (the cat sits in front of one). It seems like the boiler is cycling too much to me. When I skim, will this alleviate the problem, and will not skimming sooner rather than later affect my oil consumption? Of course there is all sorts of snow on the ground--been that way since before Thanksgiving--and Christmas is coming.

I read in Dan's book that the radiators may not get hot all the way across when the temp outside is not that cold, so I guess that question is answered. What about turning off radiators in rooms I am not using, not advised? I did size the new boiler to the amount of radiation I had in the house. I have the 629 Megasteam and I have 635 SF if all the radiators are open and installed. One has a leak so it is currently disconnected and that valve is closed while we are repairing the crack--trying an epoxy caulk that supposed to get hard as a rock. It has but I haven't hooked it back up to see if that did the trick.

Guys (and gals too!) you always have great advice and I will follow through. Thanks so much! This has been an interesting learning curve.

Fred

If the boiler water is dirty and has oil in it, you are probably short cycling on the Low water Cut-off, more so than pressure. Running excessively because it can't fully produce the steam in the way it was designed to will affect your fuel consumption. How much is anyone's guess. Check to make sure your Thermostat is set up for 1 cycle per hour or the anticipator isn't adjusted correctly. Something is going on there if the boiler runs for 2.5 minutes and shuts down for 6.5 minutes. Shutting off one radiator should not affect the boiler significantly. Shutting off many certainly will. Are you sure the boiler was properly sized to your radiator EDR?

Emeliza

Yes, I am sure that the boiler was sized according to my radiator EDR. I measured all thirteen radiators and came up with an EDR of 635.68 (with only 12 installed the EDR was 618.64). The boiler is a Megasteam 629. So I am either a little over or a little under depending if I have all the radiators hooked up. If need be, with all thirteen radiators on line, I can shut one down in one of my spare rooms to keep the EDR under the 629 SF of the rated boiler. I will see about adjusting the anticipator. Or maybe I should just get a new thermostat that I can set up for one cycle per hour.

I have a call into the installer. Attached are pictures of the plumbing fixtures I wish to buy to get my boiler properly set up for skimming. Will this work? Just making sure.

Fred

You won't have any problem heating that 13th radiator with the 629SF available on that Megasteam. What size are those fittings? They will work but try to make sure they are the size of the Skim Tapping on the boiler. I'd use a Brass Plug if it were me but, like I said, it will work.