freeze protection

Henry Nichols

Does anyone have a freeze protection chart or a site reference that I can be directed to for PG freeze performance. I used to have one but cannot find it.

Thanks

Henry

hot_rod

propylene glycol?

the protection rates vary from brand to brand and also type of PG.

Here is an example of the Nobel NoBurst and Dow regular and heavy duty. It also explains the 3 different temperature ratings.

hr

Henry Nichols

Hotrod

Thanks
It has been a while
Will you be at ASHRAE?
I have a concept that you need to look at using jockey boilers and the Thermodynamic Process Control made by a company here in Indy. Drop me an email and I will fill you in on what it does and the success that I have had with jockey boilers.

Thanks for the chart
Henry

Bob Forand

Hot Rod

Can you explain freeze point, pump point, and burst point ? I checked a system today and my refractometer reads protection to 8 degrees. When I look on Crotek site at 50%, it shows 10 degrees freeze, 5 degrees pumpable, and -20 burst. With temps here getting getting below 10 degrees, and the system turned off for the winter, should I be concerned ? Should I be more concerned with the burst protection ? Please help me to understand.

Jim_64

Freeze protection

Freeze is where ice crystal first forms in a fluid.
Flow is when the fluid is still pumpable.
Burst is when the fluid has frozen completely and expanded, breaking its enclosed vessel.

Hope this helps

Drew/Noble Company

hot_rod

Drew

what number does the refractometer read? I assume the burst point?

Another trick is to put a sample in your freezer, with a theromemeter. If it freezes solid at 10F you may need a stronger solution.

Personally, for solar 30- 35% hd should work. I'm not concerned about pump-ability below 20, as the pump won't fire up until the panel is within 12F of the storage. Rare to find storage temperatures below 32F. Or you have other issues

Once the sun warms the panel, the fluid will pump. it's the burst protection you want to watch, critical to you lowest possible temperatures.

hr
I'll look for you at ASHRAE, Henry.

hr

Jim_64

HotRod

The refractometer reads the freeze point. Generally inexpensive refractometers are acurate to about +/- 3 degrees. Where a high quality unit is good to +/- .5 degrees.

Drew