skimming instructions

ed wallace

no thats not a proper skim tapping on the boiler above the water line you will find a tapping with a plug in it probably under the jacket look for a metal knockout that hasent been removed

JoeA

Hello, all. The wall seem to strongly recommend skimming as it can alleviate most issues. I found this website that suggest the following:

Procedure:
1. Turn off the boiler. Find the manual fill valve.
2. Find a plug you can remove from the boiler above the water level or remove the relief valve and use that tapping as long as it is on the side of the boiler. The tapping must be at least 3/4".
3. Install a nipple with a valve into the boiler tapping. This pipe nipple must be horizontal. it must come straight out. It cannot go up hill or elbow up. We are trying to skim the surface water so the water must come out a horizontal pipe.
4. Turn on the boiler and run the boiler until it gets hot but not making steam.
5. Turn the boiler off
6. Slowly open the valve you installed making sure you are not in front of the pipe in case there is steam pressure in the boiler. Stand off to the side.
7. There should not be water at this level yet.
8. Open the fill valve slightly until the water starts to flow out of the pipe nipple and valve you just installed.
9. When you start getting water close the fill valve. When the water stops flowing from the pipe nipple, open the manual fill valve slightly so the stream of water coming from the pipe nipple is no larger than a wooden pencil. The slower the better.
10. Continue to skim until the bucket is almost full and remove the full bucket and use the second bucket while you dump the first bucket.
11. Keep this up for 4 - 6 buckets or at least an hour. I know jobs that were skimmed 2 - 3 hours.
12. When done close manual water feed, remove pipe nipple and valve, reinstall plug or relief valve, drain water to proper fill level, turn boiler back on.


Can someone please elaborate more on steps 8 and 9? Isnt the fill valve the manual feed?

Thanks

Kool Rod

Hi Joe- Here's a link to an article of Dan's which includes a skimming procedure at the end of page 1 thru the beginning of page 2.

http://www.masterplumbers.com/plumbviews/2002/BasicSteam2.asp

Dan advocates "cold skimming" and what he says makes a lot of sense.

Instruction 8 & 9 are a bit odd ball (confusing). What you are doing is adding just enough make up water so that the boiler water, very slightly overflows, through the skimming nipple. As mentioned- the slower the better. I skimmed my boiler for 2 hours on each of 3 Saturday mornings, skimming maybe a 5 gal bucket each time. As the boiler port I used is just for skimming, I left the nipple and valve in place and just capped the end of the valve as an extra precaution against an accidental opening. I was advised that if you plan to remove the valve, leave the nipple in place and cap it, as other wise you may have a hard time getting a plug out of the boiler when you next want to skim. This of course could only be done on a dedicated skimming port.

- Rod

Frank_63

moisture in sight glass

The article points out that the area in the sight glass above the water line should be bone dry and, if not, it is a sign of oil in the water. I never knew that. I think my sight glass has moisture above in the sight glass above the water line. I guess I need to skim.

JoeA

Thanks Rod.
The installers made a skim port out of the pressuretrol tapping. they ran a nipple into a Tee and put the pressuretrol in the bushing on top of the pigtail.

the horizontal part of the tee was capped for purposes of skimming.
Burnham has a dedicated skim tap, but installer said it is too difficult to remove.They said it doesnt matter as long as the port is above normal water line.

Will this throw off my pressuretrol?

Unknown

which is why I love

Which is why I love those Weil McLain boilers, they come with 1.5 inch tapping and un plugged... put long enough nipple and capped when not in use.

Kool Rod

While not ideal it should work okay. The Burnham skim tapping is usually 1 inch and fairly high on the boiler. The tapping you are using for skimming is smaller and lower.

Theoretically the higher skim tapping has the advantage in that the rising water level floats off any oil on the boiler's sides. All that means is you might have to do more skims with the operation of the boiler between skims washing off any oil of the upper reaches of the boiler.

I don't think this will affect your pressuretrol.

FJL

Is This A Skim Tap

In the photo attached, you can see a close up of a part of my Burhnam. Can you tell if this is a skim tap?

ceksenior

automatic feed

How do you regulate the water to skim when you have an automatic feed and not a manual feed to the boiler?

Kool Rod

Frank - Not sure exactly what that is as the picture is so close up. Go to the Burnham site and look up the I&O manual for your boiler. In that, Burnham has a chart which identifies all the boiler ports in the end castings so you should be able to tell from that.

- Rod

FJL

Will Do

Thanks.

Kool Rod

I guess that depends on what brand your automatic feeder is and who set it up. Mine has a manual bypass plumbed in.
(See attached drawing) Look for something like this or a some sort of manual override feature.

JoeA

On the burnham Independent series boiler, the tapping is on the right side of boiler. The pressure relief vavle is also on the right side but towards the back, while the plugged skim tapping is towards the front.

this plug is extremely difficult to remove therefore my installers did it on the pressuretrol tapping.

good luck