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Robbie Member Posts: 41
Hi Guys-

I have been running my system now on the new boiler about a month- we have been living there about 3 weeks, maybe 4 so far... Seems to be working nicely, but two front rooms don't get as warm as the rest of the upstairs(their doors are kept closed to sequester three cats till the work downstairs is complete) Also, the bathroom radiator never seems to heat any more. However, since the weather has turned, it aint so bad. Oh- I had the Vari-valves on all four working radiators upstairs, but swapped one out with a regular. I think I may swap all, and put the vari valves downstairs, so it warms slower there, to allow more heating time upstairs before the thermostat shuts the boiler off: this may correct the cold room situation- seems the boiler only runs for a little while, and the place heats right up.

Anyway- I have not really worked out the proper skimming procedure, despite reading the manuals, Dan's book, etc... I have a 1 1/2" skim port, which comes out a 6" nipple, to a 45 down, and is reduced to a 3/4" ball valve. What I have been doing is, when the system is fired, or just come on, I open the valve, and let it run until the water comes out clean. Usually it is inky/tar black for a few seconds, then it shifts to clear water. I can't tell water level in the glass tube because it had crud in it for so long it needs cleaning.(At least not without a flashlight behind it.)

Any ideas how I may do this correctly? I always forget when I plan to do it according to the book...




  • JStar
    JStar Member Posts: 2,752

    This is how I skim...

    Open the skim port. Manually feed water in at a trickle, just til the water is streaming from the tap (so it looks like the boiler is peeing). Shut off the water feed, and run the boiler. The heat will keep the water pouring out on its own. If the water starts to shoot out violently, shut the boiler off. Repeat is necessary.
  • djthx
    djthx Member Posts: 52
    edited March 2010

    By skimming you are trying to get rid of the oily residue that is on the surface of the boler water.  You get rid of it with patience and by trickling the water out of the skimming port.  The water must be cold!  If the water is hot, then the heat will cause the water and oil to mix, and the oil will no longer be siiting at the water's surface. 

    If you want to clean the water from rust, dirt, sediment, etc, then you need to purge the boiler water.  You can also use the skimming port, or the boiler drain (follow your manufacturer's manual).  For this you should use a boiler cleaner (TSP, Scout) and follow the instructions.

    Both these things shoud be done on any new installation. and (at least) annually thereafter.  Even on a new installation, in the beginning, you may have to clean it more often because your dirty system will undoubtedly dirty your new boiler.

    Can you post some pictures?
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