rypkr937
New Member
I have a radiant floor heat system that runs off of a gas boiler.
I purged all of the air from the floor loop and closed the shutoffs assuring the floor loop is tight. I then hooked a drain hose to the boiler drain valve and flushed the boiler side of the system assuring it was water tight.
I left the boiler at 20psi with no air in the system, opened the shutoffs to the loop and turned it on. After it started heating up it blew the pressure relief valve and a mix of air and steam blasted out until it tripped the lower water cutoff and killed the system.
My initial thoughts were I had too much water PSI in the boiler so I repeated the above process, but this time turned the boiler back on with only 5psi in the boiler. I also left the garden hose connected to boiler drain valve and when the pressure began to rise I throttled it open letting some water out. This worked as it heated up for a few degrees and then suddenly a sharp rise in pressure and it blew the valve open again.
Why is my boiler getting overpressure? I'm guessing the second time that I may have let out too much water and created an air pocket that quickly heated and created a dangerous pressure situation? Yikes if so.
But the first time I fired it up what could have been the issue?
Thanks for any help.
I purged all of the air from the floor loop and closed the shutoffs assuring the floor loop is tight. I then hooked a drain hose to the boiler drain valve and flushed the boiler side of the system assuring it was water tight.
I left the boiler at 20psi with no air in the system, opened the shutoffs to the loop and turned it on. After it started heating up it blew the pressure relief valve and a mix of air and steam blasted out until it tripped the lower water cutoff and killed the system.
My initial thoughts were I had too much water PSI in the boiler so I repeated the above process, but this time turned the boiler back on with only 5psi in the boiler. I also left the garden hose connected to boiler drain valve and when the pressure began to rise I throttled it open letting some water out. This worked as it heated up for a few degrees and then suddenly a sharp rise in pressure and it blew the valve open again.
Why is my boiler getting overpressure? I'm guessing the second time that I may have let out too much water and created an air pocket that quickly heated and created a dangerous pressure situation? Yikes if so.
But the first time I fired it up what could have been the issue?
Thanks for any help.
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