Hi all, new to the forum and I am posting in hopes that someone could help me out with my boiler problems. So back in December I went to turn on my boiler for the first time in this winter and found that after the pipes made some noises the boiler shut down. After investigating a bit I determined that the issue was that the boiler was reaching the high limit on the aquastat very quickly and then shutting off as it's supposed to. I didn't think that was the normal function of the boiler since the house will never get warm like that. I PSEG tech came to check the boiler and for $196 told me that the problem was lack of flow and the culprit was a bad circulator pump. Instead of paying the $600 for replacing this item I bought a new pump for $100 and replaced it myself. I thought that would solve the issue but when I turned on the boiler again nothing had changed. The temp and pressure shoot up and reach the safety limit within minutes and everything shuts down. I can tell that the new pump is working (low humming) so I think that eliminates that possibility. However, I guess there is still some circulation problem somewhere. To tackle that possibility I tried bleeding the system of air since I read air lock could be the cause. In the attached diagram, you can see that there is only 1 place 1 can bleed the system by opening the spicket with hose in my diagram. None of my baseboard heaters have bleeder valves so I can't bleed those individually. So here is what happens when I open the spicket: if the red valve in my diagram is closed no water comes out, if that same valve is open, hot water comes out, and if the valve is closed but I manually open the auto fill valve then cold water comes out and the boiler temp and pressure go down. This to me seems like there is no circulation when the system is closed but I just changed the pump so how can that not be working? Air lock is also not likely since when I open the autofill valve i get water going completely through the system and coming out of the bleeder hose. What am I missing and what can be the issue? Many thanks for your help!!![]()
