GTO-F Duerr-Technik KK15 3L

[PrLogy]

Hello, I wanted to know how the original compressor cutoff system on a GTO-F works. We repaired the compressor that came with the machine; it was a Duerr-Technik KK15 3L. Should the motor cut off? Before the repair, the machine was running on a hardware store compressor, but it's very noisy. What pressure (in bars) does it need to operate the five humidification units?

 

[junker1984]

7 bar is prescribed for optimal operation. Depending on the age of your machine, there could be leaks throughout the directional control valves and pneumatic ram seals. Ive seen, many times on older machines of all configurations, the blue main trunk lines (PU9 fabric sheathed, plastic sleeved) degrades internally to a point that it no longer holds air pressure, and sometimes In places where you don't even hear or see the leak. So, yes, the pump should shut off around 7 bar and cycle back on when it reaches its preset low limit, which may be 6 bar.

 

[PrLogy]

7 bar is prescribed for optimal operation. Depending on the age of your machine, there could be leaks throughout the directional control valves and pneumatic ram seals. Ive seen, many times on older machines of all configurations, the blue main trunk lines (PU9 fabric sheathed, plastic sleeved) degrades internally to a point that it no longer holds air pressure, and sometimes In places where you don't even hear or see the leak. So, yes, the pump should shut off around 7 bar and cycle back on when it reaches its preset low limit, which may be 6 bar.

Hi Junker, the compressor technician replaced the pressure switch because the old one was broken and leaking air. Is it possible he didn't set it correctly to cut off at 7 bar? It reaches 4 bar and activates the solenoid, but air escapes.

We've replaced almost all the blue lines; we're missing a few from the fifth section, which we're not using because it needs a lot of maintenance. Perhaps there's a slight leak there.

 

[junker1984]

Even though you're not using unit 5, it still pressurizes and may leak. Did the tech replace the blow off solenoid? If that's not working properly, it will leak and cause the issue you described. What it does is blow off the contained pressure in the pump piston bore, so that on start up, the compressor doesn't have to overcome the pressure to begin its run cycle.

 

[PrLogy]

The technician replaced the pressure switch, specifically the section with the screw I'm pointing to. It's no longer leaking now. However, we can see that the solenoid valve (black box) activates at 4 bar, releases a bit of air through the nozzle, and then closes back up.

We will check the entire line again. But the compressor definitely should cut out, right?

 

[junker1984]

Yes, even with minimal air leaks. Look and listen for leaks when in static position and when manually throwing damps on.