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Discussion Starter · #1 ·
My boiler was working up until last week when I noticed that the water pressure was getting too high. The psi was getting close to 40 so I opened the release valve on the expansion tank, which brought the psi down to 20. After I did this water no longer flows through the heating system.
The boiler heats up and the pipes and radiators are luke warm, but I don't hear the water flowing through them.
I can't imagine the circulator just went bad. Any ideas?
 

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You did it wrong if it is a steel torpedo exp tank. You need to shut off the supply to the expansion tank and then drain all the water from it. Then open the supply to the expansion tank so it has part air and part water in it. You then need to add water to the boiler after cooling it down and bring it to the proper pressure depending on whether the house is 1 or 2 or 3 story. Cannot remember what that pressure is but I am sure Beenthere knows and can talk you thru it. You probably lost too much water your way. If it is a blue diaphram tank then you just add air to the top of it to the proper pressure.
 

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The tank was probably full of water, and the rads were acting as the expansion tank. And after you drained water from the tank. The air in the rads has now expanded and you no longer have enough water in the rads.

As Yuri said. You need to close the isolation valve of the expansion tank. Then open the drain valve, after the water stops running out, open the vent to allow air into the tank so the rest of the water can drain out. After its completely drained. Close the vent, and drain valve, and then reopen the isolation valve. If your system has an auto water feed/AKA PRV, open the manual valve to it, if its closed. After its up to pressure. Go to the rads on the first floor and bleed all of the air out of them, and then go to your second floor, and do the same. the second floor will take longer to bleed then the first floor. Your heat will work again.

If your second floor rads are about 20 foot above your boiler. Your water pressure should be around 15 PSIG.
 

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Discussion Starter · #4 ·
This worked perfectly a couple of months ago, but now it's causing me problems again. I drained it the same way, but I get nothing. I do notice that with the expansion tank it no longer gives out air when I open the release valve. It gives a little bit off water and that's it. I bled the radiators but only water comes out, no air.
Any thoughts or can I just take a sledge hammer to it?
 

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This worked perfectly a couple of months ago, but now it's causing me problems again. I drained it the same way, but I get nothing. I do notice that with the expansion tank it no longer gives out air when I open the release valve. It gives a little bit off water and that's it. I bled the radiators but only water comes out, no air.
Any thoughts or can I just take a sledge hammer to it?
Ayuh,... Did you even read what Yuri, 'n Beenthere said,..??

If you'd answer their questions about your expansion tank, We can move along with your problem....

If you Don't wanta help Us, help you,..??....Good Luck with it....
 

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Discussion Starter · #6 ·
Thanks for the useless snotty reply, but they never actually asked me what kind of expansion I had. They offered advice on both and I used the one that was pertinent to me.
If you need to know it is an Amtrol diaphragm style boiler expansion tank.
 

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Replace the expansion tank, when you get the new one use a bike pump and bring it up to 18 psi. You can test it with a tire gauge. The working pressure of your system depends on the height the water has to travel to the top rad. The formula is .433 psi per foot of height. So if you go up 30' from you boiler you need 13 psi pressure to reach the top. Your expansion tank pressure should be with in 3psi of your working pressure. Most installers will use a 15-25 psi working pressure.

Hope this helps.
 

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Thanks for the useless snotty reply, but they never actually asked me what kind of expansion I had. They offered advice on both and I used the one that was pertinent to me.
If you need to know it is an Amtrol diaphragm style boiler expansion tank.
Watch your manners. Your getting free help from top notch experts.

Don't abuse them or you can be shown the door.
 
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