Mon Jun 03 2024

EZ10K cannot complete cycles

Our EZ10K is set for 121C, 15 min, 00 dry time.  From a cold start it reaches temperature in good time (13-14 minutes), and maintains pretty steady temperature and pressure for the first 11-12 minutes.  It then begins losing pressure, and temperature along with it.  With 2 minutes left it aborts, giving a LOW TEMP message and failure on the printout.

I verified it is putting 600 mL of water in the chamber.  There are no apparent leaks anywhere.  The water enters the chamber properly when starting a cycle, and it all goes back to the reservoir at the end.  

We replaced the water level sensor today and raised the front feet.  It still cannot complete a cycle.

Any advice on settings or parts that might help?  



   RE: Sterilizers/Autoclaves Report Post
Tue Jun 04 2024Reply from AlaskaDan
avatar placemark

Mark the water tank with the water level once the sterilization cycle starts.  If it goes up, the steam is pushing water out the fill solenoid.  Once it can't make more steam, the alarm happens.


Report Post
Sun Jun 09 2024Reply from Chris-CBET
Chris-CBET

leaking solenoid, most likely air outlet solenoid, or safety release valve is leaking due to lack of maintenance. are you seeing a lot of steam in the rez?


Report Post
Mon Jun 10 2024Reply from CTL73
avatar placemark

Hello--thank you for the replies.  These notifications went to my spam folder, and I just saw them.  I appreciate your input!  I was thinking solenoids, as well.  


I just ordered rebuild kits for the water fill solenoid and air outlet solenoid, just to cover all bases.  The last time I ran a cycle I did notice how the reservoir seemed to be very full during the cycle.  So, AlaskaDan, I think I saw what you described.  


Chris-CBET, I have noticed steady hissing coming from the jet.  I feel like the jet usually sputters during a run, but this is just consistent noise.  I am seeing steam in the reservoir, but not sure it's too much.  I've exercised the release valve and air jet valve a lot.  Is there any other maintenance I can do for them?

Thanks a lot for your help.



Report Post
Mon Jun 10 2024Reply from Chris-CBET
Chris-CBET

If your safety release is leaking, it would be a lot of steam of you would know it, so we can probably rule thst out.  Air jet sounds fine too.  So I'd open theose valves and see what the plunger amd seat look like


Report Post
Wed Jun 12 2024Reply from JV
JV

It sounds like you have a leaking valve.  open up the valves, look at the seats iff they are not smooth replace the whole valve.


Report Post
Sat Jun 22 2024Reply from CTL73
avatar placemark

Update:

I finally got around to replacing the two solenoid pistons.  Both of them looked fine when opened up, but I still installed the new pistons.  After replacing, the cycle still would not finish.  I marked the side of the reservoir at the start of the cycle and could see water spurting back into it from the coiled copper tube inside the rez.


Could the solenoid be installed backwards?  This unit was in storage before I got here, so who knows what anyone did to it previously.  Which direction should this solenoid be pointing?


Maybe I should have purchased entire new solenoid assemblies instead of just the pistons.  


Report Post
Sat Jun 22 2024Reply from Chris-CBET
Chris-CBET

Hmm, my next step would be to verify that vent and fill were wired properly. Air outlet would be powered with both the fill and vent stage. But, during heat up, chamber water would be pushed back to the rez of the full solenoid was opened, thru the bottom of the rez.  The coil however is only connected to the vent(it's purpose is to help cool the returning steam back into liquid). If the vent solenoid were open, instead of the air outlet, during heat up. That would fit 

Fill= fill.and air outlet open

Heat up = air outlet open until 210f


Sterilize = all valves.closed

Exhaust = vent open


Report Post
Sun Jun 23 2024Reply from CTL73
avatar placemark

OK, I can check for that this week.  I really appreciate this advice and feedback.


Since the unit is able to reach temperature and pressure to begin a cycle, though, does that point to all of the solenoids operating properly--at least at the beginning?  It can run part of a sterilization cycle, so why would the vent open during the cycle at all?  Would this point to a faulty vent solenoid?  If all solenoids are supposed to be closed during the cycle, would it be strange for one of them to open at all?

If it is a wiring issue, do you think the solenoid coils somehow got switched?  Or, how would I verify the wire connections are correct?


Report Post
Mon Jun 24 2024Reply from Chris-CBET
Chris-CBET

it sounds like you're not getting past heat up, not even reaching sterilization. if you're n ot reaching temp/pressure, i.e. it's taking too long, it tell sme your vent solenoid isn't closing, or the air outlet isn't closing, also possible you don't even have enough water if the water got pushed back to the reservoir. 

the only reasons a valve would open is if there was a board issue, or if it's a pressure issue. If there is a crack in the manifold, plumbing fittings, etc. When under pressure it would appear. look for steam, water, air coming out of anywhere during heat up, specifically when it gets close to the fail point. If the spring in your stem is weakened, it's possible that the pressure is pushing it open. 


Report Post
Mon Jun 24 2024Reply from JV
JV

The air valve should close between 190 to 195 degrees, you should be able to hear it close.

If you have not opened the 3 valves connected to the manifold, I would recommend to do that.  Use a magnifier to inspect the seats, if there is any pitting on the seats replace all 4 valves.  You will need 3 3mm and 1 6mm valve assembly.


Report Post

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Please review our Privacy Policy for more details.
I Agree