Q: My STERIS-Amsco Century V116 unit is taking nearly double the time since the last visit of the service team. Our facility has since decided to cancel that contract and keep the money in house. It is now mine to troubleshoot. I have looked at all seals and valves and the steam trap, and have not been able to come up with why the cycles are taking so long. I checked the printout, and it appears that it is reaching pressure and temperature but it is taking quite a while to do so. I checked service inputs, steam it at 60 psi, 287 degrees Fahrenheit, vapor quality is unknown. Water is at 60 psi, 70 degrees Fahrenheit. I am pretty new to the biomed world, any help would be greatly appreciated.
A: Sounds like the boiler is not producing enough steam. First, I would check that the elements are all working. A boiler can produce the necessary pressure and temperature but slow to get to that point, I recently had a similar situation and troubleshooting revealed that only one element out of three was working. Replacement of the elements cured that. Another problem is that depending on your water quality, boilers have a tendency to build up a lot of sediment and mineral deposits, which decrease the useable volume of steam in the vessel. The only way to correct this is to remove the elements and scrape out the sediment in the boiler and replace all the elements at the same time. It’s a good idea to replace the contactors too while you’re at it. This will make the unit more efficient.
A: Heat exchanger and check valves, drain valve and trap of chamber should help.
A: I assume when you say you’ve checked the steam trap, you mean the trap that is part of the manifold under the chamber? Not the stand-alone jacket trap. Also, for Steris gauges, you need to know an accurate chamber and jacket pressure to determine correct function. Always keep a couple good gauges on hand. Could be as simple as a steam regulator adjustment.
A: If your steam trap is plugged with debris you might want to check if there is a screen in the chamber drain.
A: Have you verified that S2 and S9 are opening fully and the seat for each valve is clean? Or does the pressure drop below 40 PSI during conditioning? If the pressure drops that low, you either have a bad heating element or lost power to one of the elements. Test the voltage at the input of the elements’ contactor and measure the continuity of the elements “with power off.” Heating elements should be ~ 22-28 Ohms.
Follow Up
I figured it out, the steam trap was plugged, and the pressure regulator was adjusted down farther than it should have been. After cleaning the steam trap, and proper adjustment of the pressure regulator, the unit ran an average of 7 seconds over projected cycle times.
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