4 replies to this topic

[cjodonnell]

We are using Syltherm XLT for a low temp chiller system used to cool an engine test chamber. Has anyone had any experience in removing moisture from the system with Syltherm XLT? We have followed Dow’s recommendation in heating the solution to 250F to boil the water from the system. After doing this and running the loop down to -50F we created a blockage in the evaporator (I’m assuming this was do to moisture in the system).

We let the system set and warm-up and did the heating process two more times. The boiling process has been carried out each time until we get no steam from the vent pipe. I have not had a response back from Dow on how to test for the moisture level in the system. Has anyone had experience with this?

[pleckner]

You don't give enough details of your entire system so I may be telling you something you are already doing. You obviously are venting the water out but are you letting it back in? Once you achieve temperature and circulate the sylthem for the recommended time (DOW), you must seal the system up immediately and pad it with bone-dry nitrogen. If you let it sit with the vent line opened to atmosphere, you will suck back in air at whatever humidity it happens to be. I would even start the padding before sealing the system up so as to make sure no air gets back in.

[cjodonnell]

Thank you for your reply, the first time we boiled the water out of the system we did seal the system however; we did not add the nitrogen blanket. On Friday and Sat. of last week we once again boiled the system at 250 F and seem to get all the water vapor out. We did add the nitrogen blanket after the process this time and ran the chiller to -50 F yesterday withotu any apparent ice blockages.

How do you know if you get all the water from the system? Is there a test kit available and/or another process we should be considering?

[pleckner]

I'm glad to hear the padding worked for you.

As far as moisture detection goes, I can't help there. Keep on Dow's doorstep until they give you a satisfactory answer. This isn't the first time this has come up.

[cjodonnell]

I'm glad to hear the padding worked for you.

As far as moisture detection goes, I can't help there. Keep on Dow's doorstep until they give you a satisfactory answer. This isn't the first time this has come up.

I just received my return call from Dow regarding a moisture test. They are sending a test kit for us to return to them for evaluation. Apparently all you need to do is ask them for the kit. It would have been nice if they put that information in the Syltherm manuals. Thank you for your response.