I have three K machines that leak badly during the night.On one it's intermittent. When I open them up to locate the source It's already dry. Anyone seen this before?

chief generally it is the heat recovery unit might try tightening the bolts and or replace
I am figuring u are seeing this after a HC is performed

I have the same problem at one of my units. We leave the loop pumps running 24/7 due to bacteria issues here. But I have the clinic staff turn the water inlet valves to the machine off because it seems there is too much pressure when they're off and leak if left on overnight. Keep us informed.

heat exchanger

In my experience, it has been the heat exchanger itself or the tubing connecting to the heat exchanger.

touche dealer

Make sure inlet pressure regulator is set correctly (18-20psi). If it is more than that it will cause the heat exchanger to leak.

Also make sure the inlet pressure stays steady with the machine off 30 minutes. I have had several that the inlet pressure is good with the machine running but climb with it off

I have had the same problem. Like the other techs said. 90% of the time it's been the heat exchanger. I think the case expands during heat disinfect, leaks, then contracts when it cools down and stops leaking. Just more fresenius goofyness.

Heat Exchanger, valve #27, Check your incoming water pressure,to high will cause the Heat Excchanger to eventually leak. Acid or bicarb ports will also cause this. Turning off the incoming water valve is not solving the problem just covering it up!!!!!

Is your RO loop direct feed. We had a problem with the loop pressure being to high in the evening when the machines were not using any water. We installed a regulator to limit the loop pressure. This reduced the number of leaking machines. All the leaks were from the heat exchanges. Prior to the change, I would replace two to three heat exchangers a month. It has been at least six months since I replaced a heat exchanger.

Hey Hilo, pressure regulators work but you have to make sure your flow velocity meets AAMI's recommendations. If you are running 1" loop plumbing you need at least 7.34 gpm flow( 4.15 gpm for 3/4" plumbing) at the end of the loop to meet the minimum 3ft/second flow AAMI calls for. Just my 2 cents worth.

Also be careful that the pressure regulators that you install do not have springs in them that RO water will corrode. Seems to me I read a post recently that said something about aluminuum springs in pressure reulators that one of the better known water companies installed. The aluminum was corroding and causing high levels in the patients.