Drainable RO vs Non Drainable

[ecolbeck]

From what I understand, some ROs are drainable to prevent freeze damage. It is also my understanding that RO membranes should not be left dry. These two things seem to be in conflict with each other. How does this work in drainable models or am I wrong in my understanding?

[Russell Lampron]

My thought is that even on a drainable RO you would want or need to keep it heated because the moisture in the membrane will still freeze and that's when the damage occurs.

[Asa Matras]

We had a drainable cdl 250. It didnt really drain and it still froze. Keep your ro warm!

[bj's sugaring]

If feel like any RO allowed to freeze will eventually incur damage, at the worst time too. Some of it may even go undetected for some time. I wouldnt trust it.