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Old man sleeping by the ocean pt.2

I had the boiler installer out yesterday and we made some changes.

1) Removed the 2-1/2" to 2" bushing from the boiler. We piped a 2-1/2" nipple to a reducer coupling into the first elbow above the boiler.
2) Checked the heights of the first elbow and ensured the point above the boiler was the highest point of the header.
3) We did not change the size of the header pipes. The installer did remind me that we discussed leaving the header the size that it was when agreeing on the Scope of Work. I also spoke to Slant Fin and they said using a bushing could cause issues, but if we use a coupling to 2" pipe, it should be fine. 2-1/2" is obviously preferred, but he said 2" should not be an issue. So, for now, it is going to stay 2".
4) Skimmed the boiler. I don't think he did this as part of the initial install. He put in some cleaning stuff that he said would break everything down and usually he said the sight glass is clear the next day.

System seems to be working much better now. I think the steam is much dryer. Due to some poor previous owner decisions, I think wet steam creates an issue where they tied in the new addition.

So, my next step is to find a Steam pro to help sort out the main venting. (My boiler installer said he was not interested)

There is one other question that his resources were suggesting I need to get resolved.........
We observed that water seems to be siphoned up one of the return pipes while the boiler is heating up. The return gets hot before the steam pipe. Also, hotter at the boiler and cooler near the tie in to the main. My installer's contacts for steam suggested we need to increase the size of the return pipe near the boiler to increase the volume of water to prevent water siphoning up. Thoughts? Has anyone seen this issue?


  • nicholas bonham-carter
    For each ounce of steam pressure, the water level in the returns will rise 1.75 inches. This is a normal occurrence, and is the reason we keep the pressure down in the ounces of pressure, as opposed to pounds.
    Can't remember your previous details, so post some pictures of the modifications you are now making.--NBC
  • gennady
    gennady Member Posts: 839
    edited December 2014
    You must not reduce pipe size of steam outlet of the boiler. Follow boiler manual to the letter on near boiler piping. I personally on Slant Fin ( my favorite steam boiler) when go to horizontal even increase pipe size to 3" or even 4"
  • Fred
    Fred Member Posts: 8,542
    We need to see some pictures of what the contractor did as well as full views of the return that seems to be syphoning water.