Repairing roof after removing dealer-installed solar panels (2018 Tab 400)

Jilong

I wasn't able to charge my battery from my dealer-installed solar panels on my last trip, so when I got home, I went up to the roof on a bright, sunny day, disconnected the panels, and tested the voltage of each panel individually using a multimeter -- zero voltage on each panel. I guess they went bad somehow, though I wish I knew why. I had just had the floor replaced under warranty and it was on that first trip after the warranty repair that the battery no longer charged from the panels.

Anyway, now I have the problem of how to repair the roof after removing the broken panels. The panels were screwed into the roof on each corner as well as bonded using an adhesive tape all around the edges of each panel. Removing the panels was quite labor-intensive using a scraper to break the adhesive tape all around each panel. Unfortunately, I have a few small scrapes on the roof where the scraper tore into the skin of the roof, and I have a lot of residual adhesive stuck to the roof.

Any suggestions for how to remove the adhesive? Is there a solvent I can safely use, or do I have to try to use a heat gun and slowly scrape the rest of it off?

What about repairing the holes and scrapes on the roof? I was thinking of just using a PVC rubber roof repair kit and cutting a section that fits over the damaged area and just gluing it in place. The replacement solar panel would then be applied onto the rubber roof section.

Any tips or suggestions would be welcome.

Thanks!

dragonsdofly

@Jilong sounds like you've got a real project ahead. Good luck with it.

NorthIsUp

You can replace the OEM panels with these, as I did: You'll need two.  https://www.amazon.com/Renogy-Extremely-Flexible-Monocrystalline-Solar/dp/B07BMNGVV3/ I had the same magic thing happen (2019 400) where the panels suddenly went bad. I know now that the polarity of the connections on the Victron solar controllers are the opposite of the no-name brand that came with mine and this magic happened at some point during my Victron upgrade. Also, my Tab wasn't used for the prior 18 months and it's stored in a public lot, so who knows?
Perhaps your floor replacement required the movement of the bed frame and thus the removal of the wiring under the bed and the tech replaced them reversed? I had my no-working panels replaced at my dealer and they said that the tops of the new panels match exactly, but the length of the news ones are slightly longer. In that manner, the new ones cover the holes. Patch them well, as my dealer did.
Can't help you on the adhesive removal, sorry. Good luck.

Horigan

To remove the adhesive, I would use 3M Adhesive remover, available at hardware or autoparts stores.  Wear rubber gloves and use a stiff plastic spatula.  I would install the replacement panels with just 1/2" 3M double sided VHB mounting tape.  No screws.  I installed the Renogy panels referenced above and am very happy with them.

Denny16

The OP had dealer installed solar panels, not OEM ones.  

“ Perhaps your floor replacement required the movement of the bed frame and thus the removal of the wiring under the bed and the tech replaced them reversed?”
The floor replacement on a TaB 400 repair does not require removing the rear bunk or frame, just the front panel, so the wiring is not disturbed or removed.
cheers

Jilong

As a minor update, after two days of scraping with a plastic scraper and liberally using half a can of 3M adhesive remover, I have managed to remove all of the old adhesive. Next I have to use a metal file to smooth down the old screw holes so that they are flush with the roof surface.

I'm actually not sure how to fill in the old screw holes. They were drilled straight through the roof and what I can see underneath is just insulation, so I'm not even sure why the screws were used in the first place as they didn't anchor into anything. I can't apply a tape on the underside of the hole, so whatever I use to fill in the hole will just drip through into the insulation. Any thoughts? Maybe I can just apply Eternabond tape over the holes directly.

Horigan

Are the screw holes located where the new VHB tape will go to secure the new panels.  You could just rely on that VHB tape to cover the holes.  Otherwise that tape you reference is what I would use, or anything UV resistant.

ReenieG

Horigan said:

To remove the adhesive, I would use 3M Adhesive remover, available at hardware or autoparts stores.  Wear rubber gloves and use a stiff plastic spatula.  I would install the replacement panels with just 1/2" 3M double sided VHB mounting tape.  No screws.  I installed the Renogy panels referenced above and am very happy with them.

I'm curious... how much VHB tape did you use? I've been having a discussion regarding adding a second panel on one of the FB groups and some have suggested using both sikaflex and VHB tape. The one I have up there was screwed in by a dealer AND sikaflex'd AND VHB tape was used, but I also see a bead of what appears to be a clear adhesive or silicon around the outer edge. The extra holes from a panel that was ripped off either in transit or when my trailer was broken into were also filled with the clear silicon. This was done about 2 yrs ago now and seems to be fine.

I don't want anymore screw holes in the roof where I plan to place the second panel so I have sikaflex and VHB tape but have been warned that the sikaflex can be pretty nasty if it ever has to be removed. What do you recommend on the amounts to use.

BTW, prior to the current panel and after the ripping off of the first panel, another dealer that did floor replacement replaced the panel with what appeared to be small amounts of VHB tape that ripped off (again) in transit or in storage by someone. I say they only used small amounts as there were little rectangles of tape left on the roof after the panel was gone. I don't want that to happen again. TIA

Horigan

I placed the 1/2" VHB tape around the perimeter of the panel, with a one inch gap at the bottom corners for drainage.  Make sure both surfaces are clean, with 3M adhesive remover or mineral spirits.  Applying heat with a heat gun will also be beneficial of applying when cold. 

elbolillo

For anyone installing flexible solar panels to their roof, a highly recommended adhesive is HelioBond PVA-600BT-04. Many of the companies that sell flexible solar panels will provide this tape for installation.

ReenieG

Horigan said:

I placed the 1/2" VHB tape around the perimeter of the panel, with a one inch gap at the bottom corners for drainage.  Make sure both surfaces are clean, with 3M adhesive remover or mineral spirits.  Applying heat with a heat gun will also be beneficial of applying when cold. 

When you mention "gap," do you mean you did not create a complete rectangle with the tape but allowed for an air/water gap within the taping? Is this all you used? Did you put any sort of silicon or adhesive around the perimeter? If that's the case and that is all you used, what I ordered and have on hand "should" work great.

Black 3M Heavy Duty 1 Inch Double Sided Tape Mounting Waterproof Foam Tape VHB 5952

It's rated for 90lbs "tensile" vs 70lbs tensile that someone else mentioned with a different number tape number, below. At first, I thought it was because their tape was white and mine was black, but apparently the 5962 is supposedly stronger, and it cost less too. (from a different seller)

3M VHB Tape 5962 Permanent Bonding Tape Roll

I wonder what your tape is rated. You also used 1/2" so I "should be" good with the 1"

Do you by chance have the number of the tape or the rating? I ask because I want to do this right but not "so right" that I can't ever get it off if it needs replacing.TIA

Here's a pic of my current panel that will remain. The lower pic shows all of the tape that was left after the previous panel was ripped off along with the sewer vent cover that had to be replaced.

The new one which is slightly longer will go directly below the current one. They will be wired in parallel. I'm currently working on adding a new charge controller and updating my WFCO to support a new lithium battery as well.

Once I get all of this completed, I will create a new discussion and link to this one as well.

Horigan

@ReenieG
I used only 1/2" 3M 5952 tape with no other sealant or adhesive.  The gaps were only an inch wide at each lower corner in case water got under the panel so it could drain out.  1" wide 5952 should be plenty, provided it's prepped properly per my above comment. 

If I ever needed to remove it, I would use high test fishing line to cut through the tape, then roll off the residue.  I figured 1/2" wide tape would be strong enough, and be easier to remove should I have to.

boathealer

Yours sounds kind of easy.....

Horigan

Ouch!

boathealer

Horigan said:

Ouch!

Looks to be 100% coverage of the Butyl tape elbolillo referenced.  If you use it, I hope you NEVER have to take it off.  Having to pry this thing off, seems like a TON of overkill. 

I will be using 3-5 strips of 2" VHB tape for the new panels I am putting on.

ReenieG

Horigan said:

I placed the 1/2" VHB tape around the perimeter of the panel, with a one inch gap at the bottom corners for drainage.  Make sure both surfaces are clean, with 3M adhesive remover or mineral spirits.  Applying heat with a heat gun will also be beneficial of applying when cold. 

Is this all you used? Did you put any sort of silicon or adhesive around the perimeter? I believe you answered above but just want to confirm. I don't want to lose another panel like I did once before. 

If that's the case and that is all you used, (1/2" VHB tape) what I ordered and have on hand (1" VHB tape) "should" work great. It's rated for 90lbs "tensive" vs 70lbs tensive that someone else mentioned. I wonder what your tape is rated. Do you by chance have the number of the tape or the rating? I ask because I want to do this right but not "so right" that I can't ever get it off if it needs replacing.

ReenieG

Jilong said:

As a minor update, after two days of scraping with a plastic scraper and liberally using half a can of 3M adhesive remover, I have managed to remove all of the old adhesive. Next I have to use a metal file to smooth down the old screw holes so that they are flush with the roof surface.

I'm actually not sure how to fill in the old screw holes. They were drilled straight through the roof and what I can see underneath is just insulation, so I'm not even sure why the screws were used in the first place as they didn't anchor into anything. I can't apply a tape on the underside of the hole, so whatever I use to fill in the hole will just drip through into the insulation. Any thoughts? Maybe I can just apply Eternabond tape over the holes directly.

I had a panel ripped off either in transport or by someone during a break-in. The replacement panel that was professionally installed was a different size. The screw holes that matched the new panel were reused by the installer and the other ones were filled in with what looks like clear silicone, along with silicone over the screw holes that were used as well. This was done a couple of years ago and everything has been fine, thus far.