Gas Panel

I have a 316 ST/ST gas panel that is supplying nitrogen to a mechanical seal. In the panel there is the supply (3 bar) which then travels through a filter, regulator with pressure gauge so we can see our supply pressure then through 2 flow meters and on to a pressure switch before going to a non-return valve then to the seal. My problem is that when there is a leak created at the seal we lose our pressure and get alarmed by the pressure switch which is set at 2 bar falling but when we re-pressurise is takes up to 3 hours for the 3 bar supply to get to the pressure switch to stop the alarm. The pipework is 1/4" and there are lots of bends and 90 degree angles that the gas would have to travel through but surely this wouldn't take so long. Initally we thought it was a faulty switch but after testing it off the system found this was not the case. I put a gauge in place of the pressyre switch and watched from the 3 bar supply to the secondary gauge and it took forever to treach the required pressure of 2.8 bar we need at the seal. The seal is used on an agitator mixing powder for a pharmaceutical plant.

Any feedback welcome.

Dev