Removing flexible solar panel

[sheakev]

I just got three new rigid monocrystalline solar panels (300 watts) to mount on my roof. Two will go behind the A/C unit, the third will go where the existing flexible solar panel is mounted.

I believe the exiting panel is screwed into the roof and then there is the grey sealant over and around those mounting positions. That sealant is quite good and will not easily come off.

If you have removed the flexible solar panel, how did you do it? any surprises?

Has anyone abandoned it in place (my current plan)? It seems that I could easily cut off the leads, notch out where my 4 mounting brackets would go and place my new panel right over the old one.

I have had excellent results using 3M's VHB tape to mount my amateur radio antenna to the roof and intend to use the same tape to mount the solar panels. Have others used just the tape? Seems screws are both unnecessary and are just inviting, leaks and possible rust in the long run. I will also use some of the same Sikaflex sealant/adhesive around the brackets as well.

I am really looking forward to having the ability to charge my batteries with these three new panels

[toskeysam]

I have 4 100watt panels that were mounted with 3M VHB tape 3 years ago. They have held up very well. I check them, along with the rest of the roof, once a year.

[PB_NB]

I am looking at getting some 100W GoPower flexible panels and based on the weight that you would be keeping with the old panel carcass, I would think that ~5 lbs wouldn't be a big deal. The tape and sealant makes sense to me! I would use something like Sika or Dicor and supplement the connection with the 3m tape. You will probably still need to secure the brackets to the roof to prevent the traveling air from pulling the panel off the roof.

Please keep us posted on your results.

[Heckler56]

Originally Posted by sheakev

I just got three new rigid monocrystalline solar panels (300 watts) to mount on my roof. Two will go behind the A/C unit, the third will go where the existing flexible solar panel is mounted.

I believe the exiting panel is screwed into the roof and then there is the grey sealant over and around those mounting positions. That sealant is quite good and will not easily come off.

If you have removed the flexible solar panel, how did you do it? any surprises?

Has anyone abandoned it in place (my current plan)? It seems that I could easily cut off the leads, notch out where my 4 mounting brackets would go and place my new panel right over the old one.

I have had excellent results using 3M's VHB tape to mount my amateur radio antenna to the roof and intend to use the same tape to mount the solar panels. Have others used just the tape? Seems screws are both unnecessary and are just inviting, leaks and possible rust in the long run. I will also use some of the same Sikaflex sealant/adhesive around the brackets as well.

I am really looking forward to having the ability to charge my batteries with these three new panels

Kevin,
I am heading down the same path this week. Based on all of the research here at Airstream Forum my expectations are removing the old panel. I have AM Solar’s mounts coming in which have the 3M tape along with a tube of Sikaflex. AM Solar has a video on removing the old Sikaflex with a putty knife (plastic) and mineral spirts. I would rather risk having some scratch marks and covering with fresh Sikaflex versus the old panel which can/could still capture sun and radiate heat into the Interstate.

David

[ROBERT CROSS]

I have removed 3M mounting tape by sawing it off with 20-30lb test mono fishing line. Clean residue with mineral spirits.

POI... my experience with flexible panels on the roof of our AS.
They didn't last or perform very well. No air circulation to help cool.
Sailing cruisers have had better luck with them when mounted on a fabric Bimini top.

Bob
🇺🇸

[vlaming]

Replaced my flexies with AM Solar stuff a few months back, using 3M tape/Sika 221 covering the feet per AM Solar info. Old panels were riveted/sealed in place. Old sealant came off with minimal fight using a plastic chisel. Drilled out the rivets to get panel off, filled holes with new rivets covered with Sika 221.

[sheakev]

Originally Posted by vlaming

Old sealant came off with minimal fight using a plastic chisel. Drilled out the rivets to get panel off, filled holes with new rivets covered with Sika 221.

Never heard of plastic chisels before -- I have now ordered a set.

Disappointed that they used rivets, seems like airstreams use rivets everywhere... But glad to know what to expect.

Thanks

[vlaming]

Plastic razor blades also come in handy working with old sealant on the aluminum skin

[JohnTF]

" gray sealant " that is a lack of info - if you do not know what it is , and cannot tells us , we can not tell you ?
Do you want to save , or do not care to if you damage the flex panel ?
Take pictures , more info .

[PB_NB]

Originally Posted by ROBERT CROSS

I have removed 3M mounting tape by sawing it off with 20-30lb test mono fishing line. Clean residue with mineral spirits.

POI... my experience with flexible panels on the roof of our AS.
They didn't last or perform very well. No air circulation to help cool.
Sailing cruisers have had better luck with them when mounted on a fabric Bimini top.

Bob
🇺🇸

Hi Bob,

I can always stick with my portable panels. I just didn't want to drill any holes in the roof.

[Rocinante]

Originally Posted by PB_NB

Hi Bob,

I can always stick with my portable panels. I just didn't want to drill any holes in the roof.

The right variety of VHB and Sikaflex are your friends. That's how AM Solar attached 7 panels to the roof of our trailer.

[ghaynes755]

Airstream uses Adseal Production silicone caulk for the edges.

[sheakev]

Originally Posted by JohnTF

" gray sealant " that is a lack of info - if you do not know what it is , and cannot tells us , we can not tell you ?
Do you want to save , or do not care to if you damage the flex panel ?
Take pictures , more info .

John, I think I found out what I needed. Lacking info directly from Airstream and not having a mass spectrometer, I was relying on the collective wisdom of this Airstream Interstate Forum. It certainty acts as if it is Sikaflex 221, which works well for attaching/sealing plastic to painted surfaces such as the roof of a Sprinter Van.

I am not interested in saving the flexible solar panel and have found that my tin sheers does a great job of cutting through the plastic of the solar panel. Thus, if I can remove what is left (the area around the riveted section) I will otherwise I will leave it in place.

[JohnTF]

Just because it's the 1st time I've heard it , doesn't mean it's not true ,
Never heard of AS attaching flexible panels ?

I mainly was looking for the answer to your question because I have a bunch of what I consider [ been doing solar for over 40 yrs. ] the best and oldest flexible panels - Uni-Solar made in Michigan but company is no longer around .
These were made for standing-seam-metal-roofs , and have a peeloff plastic to expose there adhesive , which I am not sure but appears to be a polybutene / or like .
I have not used the adhesive yet , just laid out .

[sheakev]

Originally Posted by JohnTF

Just because it's the 1st time I've heard it , doesn't mean it's not true ,
Never heard of AS attaching flexible panels ?

Now that i got a set of plastic chisels I was able to get the caulk off the fastener used to attached the flexible solar panel to the roof of the Sprinter van. The fasteners turn out to be phillips head screws with a rubber gasket.

I will remove the caulk, screw out the fasteners, apply some zinc paint (to ensure that the penetration doesn't corrode, and then seal the hole with Sikaflex. I can then proceed to attach my new panels with #M VHB and seal around the brackets with more Sikaflex. Plug everything in and enjoy capturing all those extra photons to charge my batteries.

Thanks to everyone here who helped me through this.