Hello AllNewbie here.We have a Prestige Excellence Water Boiler (came with the newly bought house) and after a 3 day away trip we returned to a flahsing hard error code E12, and after a manual reset experienced a soft code b26Using the troubleshoot guide, we knew to check the tank pressure andWe noticed the pressure was reading 8PSIG, so I pulled on the "fill lever?" gently and heard water come in and watched the gauge increased pressure to 12.The boiler subsequently came on, but the water did not get very HOT. It remained lukewarm.I even ran a standby H firing test, and the water did not get very hot. I need some more steps on what to test/ check for, before calling in a pro. What pressure should the tank read, ideally (so I can fill to that level.)Is there a chance that there is air trapped in the system? and if so, how do I relieve that air? (Diagram would be useful)Any other common reason/ explanation why this may have happened, and how to remedy it?Most sincerely
That boiler locks out around 10 psi. The fill valve is usually set to about 15#. You likely have a leak somewhere in the system and a fill valve that is not working quite right.
You immediate problem sounds like air lock. You can check that the eliminator on top of the boiler is open. To get more specific advise, you would have to post a picture.
I am out of town this weekend. There are much smarter folks on here that can help you out.