Hello, I a gas boiler Saunier Duval 28E TWIN 1996. I had to change the expansion tank (expansion tank standard commercial inflated to 1.5 bar of nitrogen) and after startup I see the pressure rises to about 3.8 bars (60 Â°) and therefore the security group lets out the water which naturally causes a pressure drop below 0.5 bar and stop the boiler. At what pressure can mount the circuit when the boiler heater? The pressure does not vary when the boiler is not heating. When stopped for 8 hours, no change in pressure after it lowered again until completely cooled (20 Â°)!..
If the pressure of 3.8 bars is normal, what does this mean? This boiler is also equipped with a vase "air pressure/overheat thermostat. This equipment can be questioned?.
Hello, Pat38 Thank you for your help but everything is perfectly drained. It seems that part of the expansion tank containing water pressure cold water system of the house. Is this normal or should there be a limiter to limit the pressure in the expansion tank when filling the circuitry to replace the boiler in operation? Thanks in advance for your help
Hello, To work, your boiler needs the circuit or cold pressed, 1 to 1.5b. Before putting into service, ensure that this condition is met. To do this, blow the circuit at each radiator until it no longer contains air. If additional water is needed, open the finish very lightly. Only then turn on your boiler. If the circuit contains no air pressure difference, circuit cold/hot circuit, is between 0.5 and 1b