Hello Everyone :

My 2008k from hell has a new problem. When temperature is commanded for 37.0 at an 800 flow, the temperature drops to 34.9 and stays there. The Fresenius tech I spoke to thinks that I may be losing temperature through the hydroblock. Does anyone else agree with this assessment? I replaced the hydroblock on this machine on 3/8/08. I did have to adjust the loading pressure regulator almost entirely clockwise to achieve 23 psi.

Thanks,
Lumpy

does the temp drop at 500 flow also
if it does check heater rod
if it does not check balance chamber

When using new loading pressure regulators you have to swap the spring in it.You should not have to screw it in all the way clockwise...It should be just about all the way out counter-clockwise.That is a sure sign you have a weak spring in it.If you have a dialsafe filter you have to have 24 to 26psi.

If you replaced the complete hydroblock assembly, Down south tech is right. You have the wrong spring in the regulator.

Im curious to know if you ever found out what the problem was. I am having the same problem with a home patient's machine

Hi Debz :

This particular machine had a bad sensor board that had been ordered over night from Fresenius. As I am sure everyone knows, their quality control is not always stellar. The first thing I noticed was that when I tried to calibrate temperature, I could not achieve a DAC value higher than 50 at 37.0. A normal DAC value for a temperature of 37.0 is 130 to 170. I swapped the sensor and functional boards from a known good machine and was then able to calibrate temperature to 37.0 with a DAC value of 150. We then ordered another sensor board from Fresenius and this time their quality control was stellar.