I'm starting a new thread because our issues have drifted from asbestos to a possible leak in our boiler. We have gotten a bunch of solid advice on this previous thread on asbestos removal/reinsulation and the beginning of our hot water troubles
. A quick update: We're a 24-apartment coop, oil-fired burner, single pipe steam. We have a fair amount of master venting at 3 locations. 60-70 radiators.
A couple days ago, a boiler technician found that we were losing about an inch of water per hour, by the gauge. His guess was that we have a leak in an buried return.
Today, we had a different company come out for a second opinion. They installed a water meter on the boiler so we could see how much we're adding. Our first reading showed 11 gallons in an hour. They looked throughout the basement, examined the pipe that is exposed and looked in other places where the pipe is just below the surface. Their opinion was that we don't have a major leak in the returns, because there is evidence that they have been replaced or patched recently, because pipes don't corrode in dirt, because the kind of concrete we have is not corrosive. They recommended we should start by going through each apartment and checking for hissing or spitting vents, or leaking shut off valves. He thinks we could be losing a lot of this water through the radiators rather than through a leak.
Does this seem like a reasonable theory?
It makes sense for us to go through the buildings' radiators. I just didn't think we would do it in the middle of an emergency hot water/heating crisis. It brings up other questions for me. For example, should I go out tomorrow and buy 50 radiator vents?! A mix of Gorton 4, 5, 6, ...?
I also just received an infrared camera attachment for my Iphone in the mail today. Over the weekend, my plan is to take photos of the returns in the basement, looking for leaks. We will also test the low water cutoff, on Jamie Hall's advice.
Our primary boiler technician is coming back on Monday to see about determining the source of the leak. His strategy would be to add a shut off valve to each branch of the steam mains, then open them one at a time with the boiler running to see which loop is losing water. I may be misunderstanding this strategy.
Any advice at this point?