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My tenant called to complain that their gas bill last month was way too high, and they thought the water in the boiler was too rusty/dirty. I lived in this unit for 10 years myself and sometimes had difficulty with surging. I always wanted to skim it but the skim tapping isn't installed and just drained it many times. Realized the tenants probably haven't drained it in a few years. I went over to look at it, opened the drain and nothing came out. Unscrewed the drain still nothing, could see a block. Put it back and ran a wire through it, got a good stream going, drained and filled until it ran clear. Added some boiler cleaner and had them fire it up. Wish I saw what it did before - it's totally short cycling now. Wonder if the cleaner made it worse? Runs for about a minute, water line plunges, a few bounces on the way down, until the LWCO cuts in. You can then hear water running back down through the header/equalizer until the level comes back and the boiler comes back on. Water quite rusty again after the first boil.
The skim tapping isn't easy to get to on the boiler, but there is a capped 1" long nipple coming off of the riser 4" above the furnace or so. Can I skim from that? I'd have to raise the water level quite a bit to make that work.
Hearing the water coming back through the equalizer made me think it might be a clogged wet return instead of a dirty water problem. The main vent also looks like it had dirty water explode out of it at some point, not sure if plugged. I tried to drain the return when I drained the boiler, but couldn't loosen the plug at the tee on the bottom. Probably could put more force into it, but I had a 30" cheater pipe over the 10" adjustable wrench and I was worried about breaking the fitting at that moment. I know I've cracked one of the cast fittings on the piping before, don't remember what I was doing/why though. But it made me gun shy.
I also thought it might be overfired? The flames are quite large, with a lot of orange over the blue. The Burnham manual makes it seem like there shouldn't be any orange? But my friend's boiler looks the same.
Looking for advice on what to try to tackle from these first, or something else entirely. I may need to do all of the above but hoping there's a clear first point of attack.