SOLKOTE HI/SORB-II Selective Solar Coating has proven to be an extremely durable selective surface for the life of the collector – in this case, 30 years including 8 years of stagnation/neglect. A gentle cleaning of the surface combined with some seal replacement and these Gulf Thermal collectors will be serviceable for many years to come. The coating shows extreme resistance to UV and moisture degradation.
Dear Robert Aresty-
I spoke to you last October about cleaning some 30 year old solar collectors with the Solkote coating. Thank you for your kind advice – 30 year customer service is pretty rare and special. I said I would send you some pictures and here (belatedly) they are. I got the panels from a house where they had been on the roof for thirty years.
The system had not been running for eight years or so as the current owner had bought the house and did not know how to run it. So they had been baking in the sun for awhile. The panels had to be removed to repair hail damage to the roof and that’s when I bought them.
The rubber seals around the inlet and outlet pipes had shifted over the years and some dust had drifted into the collectors. I took the collectors apart and used a soft bench brush to loosen the dirt and then blew the dust away with a leaf blower.
I took some pictures and tried to capture the appearance of the coating. In the pictures, the cleaned coating looks grey, but it is such a flat black that I think the camera can’t capture it. In reality, it is a deep black. The small cleaned areas in the pictures are closer to the true color. I did not see any flaws in the coating.
Anyway, thank you for your advice and a great product.
John K. – Fort Collins, CO
Gulf Thermal collector, model KYSM-32
Installation date: “The current owner of the house they were at said he thought 1980 or so when the house was built. This is what the former owner told him. The plumbing and storage tank in the basement appeared to have been put in as the house was constructed.” – John K.
“The uncleaned collector.” – John K.
“Partially cleaned – The darker spot is where I brushed it with a shop brush. I ultimately got the surface cleaner than this with the technique of brushing with the shop brush while using the leaf blower to blow the dust away. That is pretty close to the actual color of the cleaned collectors.” – John K.
“The dark spot is where I wiped it with a wet rag.” – John K.
“Cleaned – It looks grey, but is actually a deep black. I wish I could have taken better pictures. The only way the black shows up is when there was a contrast with an uncleaned area. All my pictures of just the cleaned surface look grey, when it is really a very dark flat black.” – John K.