Temp tolerances for AC refrigerant lines

D107

About 5 feet of our old 1980s refrigerant line as it descends downward will be covered by closed-cell spray foam, which, while curing, reaches temps of up to 200 degrees F and then drops off after about 15 minutes. What effect might this have on the two copper lines, the rubber tubing on one of them, and the refrigerant inside? Should refrigerant be drained first? See photo.

ratio

A bigger concern in my mind is gluing the lineset in place like that. I'd like to see some kind of sleeve around it to facilitate repair/replacement of it. Perhaps some of that black plastic corrugated drain pipe could be split and slid down around it? That would also serve to isolate the lineset from the curing heat.

D107

Thanks that's an interesting idea. Though I'm thinking if it had to be repaired at this point--it's over 25 years old--I'd probably replace it by going through the gable wall instead of the roof. I would hope the same lines could be used on a smaller AC unit. (this is 3-ton.) What you can't see in the photo is that far down it gets to within two inches of the roof deck, and I'm pretty sure there's no nail guards put on the top of the deck, so perhaps I could glue in a metal plate under the decking above the lines in the event of a future re-roofing.

ChrisJ

David107 said:

Thanks that's an interesting idea. Though I'm thinking if it had to be repaired at this point--it's over 25 years old--I'd probably replace it by going through the gable wall instead of the roof. I would hope the same lines could be used on a smaller AC unit. (this is 3-ton.) What you can't see in the photo is that far down it gets to within two inches of the roof deck, and I'm pretty sure there's no nail guards put on the top of the deck, so perhaps I could glue in a metal plate under the decking above the lines in the event of a future re-roofing.

Depends on how much smaller of a unit and what refrigerant it has.
Also keep in mind there's likely going to be a huge refrigerant change in a few years, who knows if your lineset would work.

Make it easy to change, you'll be thankful later.