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New oil introduced to system, I think...
I have a fairly new crown BSI boiler.
Soon after the install it was very noisy, and the contractor came and skimmed it. Then it was working fine for a while.
Recently I had done a little bit of work in the system, and it seems that new oil is introduced.
1) I took out a radiator and re-connected it.
2) I tightened a couple of valves (thank you for the help with this issue!)
3) installed some new vents
4) there was a leak in the gas line and one union was tightened and another was replaced.
Could any of these introduce oil to the system?
The system has become very noisy so I went to check the water and I can see a layer of oil on top, and more brown color in the water than before.
I changed a bunch of the water and it worked temporarily, but I know it is not the solution and not very recommended. Also, the noises did come back, and I can still see the oil.
Short of getting the plumber back here to skim again...
what can I do?
And, what do you think caused it? (so I can try to avoid this in the future)