inconsistent high boiler pressure


Hello Can someone help me with a gas fired boiler. I have an old American Standard boiler that has developed a problem with tank pessure exceeding 30 psi. which blows the 25 psi pop off valve. And then returns to 10 - 15 psi for hours at a time and then out of the blue it builds to much preesure and the safety valve goes off? Coincidence or not this problem started immediately after a "free" inspection? I have so far replaced the pop off valve and the water pressure reducing fill valve. I also notice my Aquastat was set to maximum temp of 200 degrees. Other than the pressure the boiler is working fine. Does anybody have any ideas?
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Silo

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Silo wrote:

Be 100% certain that *no* water is being fed to the boiler, even via a bypass/manual fill valve. One good tipoff is if the feed pipe feels cool.
If no water is being fed, the pressure should not go up dramatically, UNLESS the expansion tank is waterlogged. If it's a diaphragm tank, it may have failed internally.
Jim
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Speedy Jim wrote:

I should have added that control failures might cause high pressure. For example, if the circ pump(s) quit running and/or the aquastat stuck closed, the boiler could fire continuously and it would wind up steaming till the relief went.
Jim
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Speedy Jim Wrote:

Thanks Jim for the advice. I can tell you the boiler does not fire constantly. The circ pump seems to be running fine. I put a gauge on the expansion tank valve and got 0 psi? I tried to put air in the tank and it wouldn't take it. is there some kind of "special" adapter for this? I put my tire chuck on there with 160 psi from my air compressor and I couldn't get it take any air?
--
Silo

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Silo wrote:

The Schrader valve on the tank may be stuck. You could try to operate it with a small diam drill bit or the like.
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Check all valves maybe the tech shut off the valve to the expansion tank by mistake or something else. Turn off any water feed and get it to 10 cold and see what happens.
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I am looking for a top freezer refrigerator with the maximum capacity for the refrigerator at the lowest cost. I don't need any of the bells-and-whistles which seem to come, inevitably, with the larger sized, better quality refrigerators. The largest refrigerator I would find with the conventional top freezer style is the GE Profile Arctica refrigerator with a capacity of 24.6 Cu. Ft. It is model number: PTS25LHSWW. However, in reading posts to this group about GE refrigerators I have seen a lot of criticism of the quality of GE products. Does anyone know anything about this model? Or are all GE refrigerators of poor quality these days? And if so, what company, if any, has well made refrigerators? Thank you for your help. Dorian
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Dorian wrote:

Don't know much about top-freezer models. We just bought a GE Profile side-by-side to replace a _6 year old_ Amana that died on Thanksgiving day, compressor. I'm kinda down on Amanas right now. Prior to the compressor failure, we had lost the auger motor, and we were on the 4th icemaker unit. Meanwhile the 20-some year old GE in the garage just keeps chugging along, one of the reasons we decided to go with a GE to replace the Amana.
Jerry
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