During calibration it will only go up to 36.3 on the external meter. I have tried the ff: NTC 2,3 , all the boards, cable's , heater rod, hydroblock and power supply.

Will it go into heat disinfect? If so, does it heat up to 80 +/- degrees? Any flow errors or valve errors?

Yes, no flow errors or valve.

What is the screen reading? Maybe time for your external meter for a calibration.

What is the voltage to the heater rod?

I had the same problem about a year ago and I finally changed out the hydroblock and discovered the seal was leaking. The mach came up in Temp and was able to calibrate Heat Temp Control Post the hydroblock seal replacement not before. GOOD LUCK let us know what solved the problem PLEASE!!

It was the hydroblock, it took me a week to get this solve since first i got a hydroblock from a good machine but when i check back the record from the good machine i have replaced the hydroblock gasket before and i found out from Fresenius Tech support that if you have the old style hydroblock and change the gasket you are going to have a problem with the temperature. Thanks to all!

There are two different hydroblocks with two tops and two different seals. Pre-1998 Fresenius used a hydroblock that had the heater rod threaded into the thick top. Post 1998 they started using the plate that was screwed to the top, and held the heater rod in. Those two styles have different seals and tops, and if you mix them up you will have problems. The post 1998 hydroblocks had an immediate problem when they first came out, they warped badly and leaked, because they are thin and weak around the heater rod. We changed out about 20 hydroblocks in six or eight months on brand new machines back then because of this. The fix for this is the 1/2 inch thick stainless steel reinforcing block that fits around the air chamber beside the heater rod. Until those were installed on the thin top hydroblocks, you could not keep the top from leaking. In the older hydroblocks a problem that I am seeing is the bushings that the screws thread into are rusting, and by the time that you get the bushing out the threads for it in the plastic have been ruined and the hydroblock is junk.

Ktech, good information! You should be a tech support at Fresenius.

Ktech - Dumb question but I haven't replaced a hydroblock. Do you just replace the body or the entire assembly? If the body, what parts do you replace when you have it all apart. There are a lot of o-rings and gaskets and such that maybe should be replaced when it is torn apart, Right? or Wrong?

Ktech, in the 20 hydroblocks you replaced did you get a credit from Fresenius, just curious.

If the bushings rust out the hydroblock assembly is junk. I have seen rusted bushings for the heater rod screws, the pressure regulator screws, and sometimes the other screws that hold the top down. And yes, we were able to warranty those hydroblocks when we replaced them, although, true to their way too common practice, Fresenius may not have issued the RGA's for many of them and we may not have ever been issued the credit for the returned parts. We replaced the complete assembly bad thin top hydroblocks with the older style threaded heater rod style. After the stainless steel reinforcing block came out, we did not have any more problems. I think they issued a service bulletin about the reinforcing block back then, around late 1999 or 2000.

I had the same problem in my 1995 model H's. The top would start leaking and when I would take it apart to replace the gasket and warped cover, the threaded inserts would come out with the screw because of corrosion. I got to where I just ended up replacing the entire hydroblock anytime they leaked.

As far as the RGA goes, they will try to screw you on that. I was upgrading to digital heparin pumps and was told that I could get RGA credit for the old Actuator boards. Once I did the upgrade and sent them in, they denied me credit because they weren't the newer style boards. 20+ boards x RGA credit ($150 per board?)... we lost a LOT of money.