Long life sealant for solar panels

[russ_drinkwater]

Hi, What is the best quality product (silicone sealant) brand for sealing the edges of the solar panels to help prevent water/moisture incursion into the panels?
Sikaflex is a mainstay here in australia.

[dgd]

PVs tend to be already well sealed at their edges. It would be highly unlikely that user applied additional sealant would be necessary.
Although, I have seen junction boxes come off or loose where the siicone sealant has dried up/broken away/opossum chewed and then resealed/glued on using normal external quality builders anti-fungal silicone sealant/gap filler.
NZ/OZ manufactured sealants tend towards good quality but some of the asian offerings have a higher chalk content IMO

dgd

[CDN-VT]

I use fast curing urethane , for my auto windshield  also . I first use the primer & let sit for 5 min . then a small bead & let dry 24 hrs . cleanup sucks on this stuff.

VT

[BioPower]

The Marine grade version of Sikaflex is the ducks nuts, sticks like s#!t to a blanket. Seals boat hulls permanently and never leaks.

[russ_drinkwater]

Thanks for the replies. I know it is probably over kill, but it can not hurt to seal around the top edges of the frames and covering panels.
Easier for me to do it now than to have a potential problem in 10-15 years time. We do have a few panels here which are over 25 years old and have not suffered on the water/moisture ingression front as yet. Better safe than sorry!
Yeah we do not have the kia chewing machines in australia!
I would not want solar panels at a higher altitude in nu zuland!
Our possums were a good export though!

[Vic]

Hi russ..,

Would avoid Silicone sealant/caulk.  It has relatively poor adhesion,  and most cured Silicone sealants do not adhere to cured Silicone sealants.   This makes trying to do any touch-ups after the initial sealant cures,  impossible.

Agree,  that single-part Urethane caulks and sealants are the way to go (if you really feel that you must do this).   Am not a big fan of Sika,  though.

In the USA,  the BASF NP1 sealant/caulk (used to be Sonnebourn NP1).  In the past couple of years,  the name has changed to "Masterbuilders MasterSeal NP1"  by BASF.

All of the Urethane sealants have terrific adhesion,  and if need be,  an additional pass can be made onto the cured sealant.

BUT,  also agree,  that if the PVs are of good quality,  you really should not need to add any sealant.

One risk of leakage can come from removing and handling PVs that have been in service for some years,  as this can disturb the seals between the glass and the frames.

Just opinions.   Vic

[CDN-VT]

I agree what VIC posted .
If I have to remove panels for a new re-roofing , then all panels need to be checked for seal breakdown & resealed . I use hard Nylon razors to remove the old pealing silicone & use fast cure single-part Urethane caulking , duel parts sets hard a rock.

This is better than Shite 2 a blanket , its Shite - 2 - Shite  upstuck .

VT

[russ_drinkwater]

My only concern is water incursion from the top (covering panel) where moisture sits alone the bottom of the frame after rain or heavy fogs we sometimes get here. Not so much in summer when the heat is intense after rain storms, but during periods of up to week when we get the occasional rain depression!

[CDN-VT]

I have used light liquid silicone , after a real good cleaning as the best as I could .
It's like vinegar and starts to jell up in 2 mins , so you add some , wait 5 min and carry on till you get your bead .
I used this on a leaking Window port on my sailboat . I had tried to reseal it a few times , so the last time was strip it & clean ,reseal & the add liquid silicone , worked for 25years .

VT

[russ_drinkwater]

I think a clean well prepared surface is the key to success. One of my friends brother worked in bus maintenance and they used sikaflex when re-attaching panels to commercial buses after their inspections at certain intervals! After 5 years and next inspection the panels were still
securely attached and required the adhesive to be cut away to allow panel removal.
All surfaces were of course under cover and no UV exposure except for heat.

[clockmanFrance]

Heres the stuff I use in Europe. I couldn't get white!.

Excellent shelf life.......Takes 3 to 7 days to really set,....... excellent with electrics, ........and has very good adhesion with plastics, metal, glass etc.

Recommended by a Sharpe panel manufacturer assembler 7 years ago.

I got hold off some Sharpe seconds at the assembler, tested and picked the best, then got busy with the silicone. As you say Russ, its a clean joint that is the key. I did these panels when they were new, if I wasn't sure then a Isopropanol alcohol wipe got rid of any grease.

The seconds were bad QC on assembly.

The number 2 photo shows the rear of my No 2 tracker 6 years later with the silicone repairing scratches in the rear film and the junction box areas. The 2kW tracker in the background has Yingli Panda panels.

[clockmanFrance]

This 3rd photo shows the front of the panels, just surface marks on the glass as I never wash them.

As I was unsure if the QC of the interior sealing was done properly so I used a good tidy bead of silicone ensuring it went down between the frame and the glass.

6 Years later the silicone has withstood the Sun/UV and still working, and the vegetation is improving, its a wet climate here in Normandy.

[russ_drinkwater]

Thanks for that clockman.
And greetings from the descendant of a vet who died near normandy.
I was not too concerned about water invasion, but after reading and seeing a few panels suffering from it I thought it best to be safe!
And better to fall off my roof while I am a bit younger, lol.

[CDN-VT]

https://www.youtube.com/watch?v=4rQewDKkEG4
Looking for the item you posted Clockman

http://www.baxgroup.co.nz/Siroflex.html

https://www.amazon.co.uk/SX-Trade-Strength-Pvcu-Silcone/dp/B00X5XV2MY/ref=sr_1_9/277-5910483-5775123?s=diy&ie=UTF8&qid=1464573364&sr=1-9&keywords=SX+Siroflex


Last one look correct ?
Canuk dude now , But Born just off the coast from you , Jerseyman I is .
VT

[clockmanFrance]

Hi CDN-VT.

No, none of your links...... Deffenitly not a grab or fill adhesive.

The Guys at Sharpe insisted that only 'Siroflex LMN 2001' Low Modulus silicone should be used as this has the correct chemicals that will not damage or seep/leech into the PV Silicone panel laminate joins.

I feel sure there are now more specialised Low Modulus silicones available, it was 7 years ago when I got my box full.

'Siroflex LMN 2001', still being made and are still for sale.......  http://sealants-direct.co.uk/product_info.php/siroflex-lmn-2001-silicone-p-58        ebay has some for sale.