I have three machines that take up to two or three rinse cycles to clear of bleach. Anyone seen this before. It just started recently.

The usual really simple cause of this is a bicarb O ring that has come off the wand and is lodged in the rinse port on the front of the machine. That causes the wand to disengage just enough to stop the flow, but not far enough out of the machine to deactivate the reed switch. Take a small flaslight and check the rinse ports and see if there's an O ring stuck inside of them.

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I've seen this many times. In my experience, the culprit is the acid spike not being plugged into the rinse port fully. In this way the reed switch is engaged, but the needle valve is not open all the way.

Thats also a good point, Longhair, if the plastic portion of the reed switch cracks it can allow the port to become loose and the port may not be sticking out in the front far enough to allow good, solid engagement. Many,if not most, of the reed switches have small cracks, but as they get bigger, the port will move around and may move back towards the inside. If you do not clean your reed switches with vinegar when you do PMs the acid that dribbles around when you unplug the wand will crystalize in the cracks and enlarge them more rapidly. Also, if your staff is not using the bleach disinfect bottles and they are just dropping the wands into an open container of bleach, that will cause the plastic and the glue that holds the magnet in to deteriorate. The magnet will begin to crack and come loose, and as it begins to stick out farther, it will also cause a bad fluid connection with the port. Straight bleach is really very hard on the plastic of the wand plugs, and if you check, the price of a new plug is about the same as buying a whole disinfect bottle. And all of the parts to repair the bottles are available seperately. And on older machines, sometimes the port is just worn out and will not properly lock the wand in, and after a minute or two it will disengage.

Ktech and FMCLongHair Thanks. I'll definitely check these suggestions out.

i have one if you are checking from the blue hanson? i have noticed that bleach gets "stuck" in the ball bearings. I put the mach back into rinse and the take the hanson off and pull the connector back and forth a few times and let the water rinse in between. and what the others have sugg

If you are checking from the drain, bleach can also come from the drain board.

Alot of times the rinse ports are not sticking through the cabinet far enough to let the snap ring on the spikes lock in. Fresenius has a stopper, part# 565682, on the front of the hydraulics that is shorter than the one from the factory that will help,it got rid of our problem.

What has Fresenius told you about using that shorter stop on the front of the hydraulic drawer? Have they told you that this is an authorized fix? And if so, I wish they would put out a Service Bulletin about it. Around 1998 they changed the machine case slightly, and I think they made it thinner. That meant that the stop had to be slightly longer to put the hydraulic drawer in the same position since some of the parts come through the case and the back covers. If you have ever changed a machine case or a whole hydraulic drawer this can be a problem, because you have to use the correct stop(s) for whichever parts you have interchanged. The old case/drawer had only one stop right above the circle that the acid and bicarb lines go through, and the new style has two stops beside the circle. We are talking about maybe an eighth of an inch difference, but that is all you need to make a good connection. If you do try to use the shorter stop on a new case, you may be causing your reed switches to rub against the case and that may cause them to break when pressure is put on them during connecting the wands. But you are also right, as the case gets older and warps a little sometimes it is difficult to get enough of the port to stick out so that a good connection can be made. And one other simple thing that can cause this problem is not putting the heater wiring in that little notch in the wiring manifold housing when you put the hydraulic drawer back in. The thick heater bar wiring harness that comes down from the power supply gets pinned between the plastic manifold housing and the case, and does not allow you to push the drawer in as far as it needs to be. You can save yourself a little trouble by just taping that wire in place in that notch the first time that you open up a new machine.

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Actually,Ktech, the service rep for this area was the one who showed me the difference in the original and the one you order from parts. In fact he gave me 4 or 5 to see if that fixed my problem. Sorta like the deair brushes being shorter, for whatever reason, some replacement parts are different from OEM.