Re: problem with nozzle back flush

At low pressures (e.g. below 20psi) this occurs, although on my DiVa it is 
usually only below about 12psi. I believe it has to with the amount of vacuum 
applied at the waste tank. My house vacuum is about 9psi on a good day (I have 
extra ports on my tanks for measuring with a digital manometer -- long story).

Here is a convoluted work-around that I have which was actually the spurious 
effect of another fix: One day my DiVa decided to backflow waste through the 
collector when I was in nozzle flush. It started suddenly and I still haven't 
discovered the root cause. As a repair, I routed a second vacuum line from my 
waste tank to the nozzle flush vacuum line after it comes out of the solenoid 
behind the fluidics knobs (can't remember offhand what number solenoid, but 
I'll look it up for any interested parties). This is routed to a quick-connect 
at the tank, so I am now using all four ports on my tank (normal waste, nozzle 
wastem vacuum source, and measurement port). By doing this, I have completely 
divorced the collector waste from the nozzle flush waste so there is no 
possibility of backflow unless my entire waste tank fills up.

Now, the workaround that I discovered with the low pressure sorts is that when 
I nozzle flush, if i pinch the new waste hose just the right amount, it 
attenuates the vacuum applied and I get a proper fill stream.

Sounds easy, doesn't it?

-Christopher Bare
Senior Flow Cytometry Specialist
Sloan-Kettering Institute


>From: Simona Ronzoni <simona.ronzoni@ifom-ieo-campus.it>
>Date: Fri Dec 16 07:38:16 CST 2005
>To: Cytometry Mailing List <cytometry@flowcyt.cyto.purdue.edu>
>Subject: problem with nozzle back flush

>Hi all,
>I have a problem with	Fill and nozzle flush on Facs Vantage SE + 
>turbo optional
>I work at 20 PSI and when the nozzle is clogged I put on fill and I 
>push the bottom nozzle flush, but the stream go to back very slowly 
>and  is not enough to clean the nozzle.
>This happen also when the nozzle is not clogged!!
>
>Any comments are welcome
>Many thanks in advance
>
>Simona
>
>
>-- 
>Simona Ronzoni
>Flow Cytometry and Imaging Core
>Experimental Oncology Department
>European Institute of Oncology
>via Ripamonti, 435  20141  Milan   Italy
>Phone: ++39-02-57489880	Fax:	++39-02-57489851
>e-mail: simona.ronzoni@ifom-ieo-campus.it
>http://www.ifom-ieo-campus.it
>http://imaging.altervista.org