Solar panel _functional appearance looks faulty?

bro'

Hi
I have 4 flat panel solar collectors on my south facing roof. Whilst the solar system seems to be functioning OK I think that one of my panels may not be correct as its appearance is alot different from the other three.

What do people think of the visible appearance of this panel [see picture below]. This is the same appearance no matter what the weather is i.e full sun or not and to me it lools like it may be faulty and I am not getting full benifit of the panels?

Thanks

bertie1

Looks like condensation inside the glass, the one next to it is kind of starting as well. When I was deciding on which ones to buy that was one of the problems with some of the flat panels which was pointed out to me so I went for tubes.

MickLimk

Agree with Bertie1, looks like your two middle panels are not right. I'd get the installer back as they must provide a minimum warranty with the panels.

What brand of panels are they? Do you have any pictures from the inside of the roof?

bro'

Thanks for the feedback...

I have contacted the supplier and await response, there is meant to be 10yr warranty on flat panels and system is in under two years.

Panels are ''Sunset Energietecknik, CC -A/ FBlue''

Micklmk, I can get pictures of inside the roof but what will this show?

I assume condensation in the panels is not good and would effect performance -right?

MickLimk

Photos of the inside might show up something obvious as to why they're condensating. Mightn't be worth the effort as quite likely there mightn't be anything to see from that side either.

Yes, the condensation will be affecting the performance of the panel. It's effectively like having your own private cloud over two of the panels!

Do you know if you have any heat dump arrangement or what size your expansion vessel is? Just wondering if damage has been caused by repeated stagnation of the panels or just a faulty pair of panels.

MickLimk

Just realised that you have 11.2m2 of panels (4x 2.8m2 if their website is right)! What size cylinder have you??

bro'

Got talking to solar supplier and he told me that 'this is normal' and is caused with temperature and humidity. He says he has passed it onto the panel supplier where he has asked them to contact me to explain this?

I have a 'tank in tank' setup with 200l domestic and 600l buffer tank.- 11m2 solar collectors. I do not think i have a heat dump. My 'white' expansion tank is 25l I believe.

Is there a quick way of checking the effectiveness of 4 panels as opposed to 2 i.e under full sun at midday what temp would you expect on solar collector flow for 11m2?

thanks

I'd have thought that the condensation would quickly evaporate away when (if) the sun ever decides to come out again.

bro'

been away ....

dolanbaker,
the panels do not change [i.e condensation evaporate] with full sun

I am not convinced that as panel installer says that this is normal!

I am trying to contact the manufacturer directly but wonder on other flat panels users with similar symptoms?

CJhaughey

I have FP and they do not look like this.
Tell installer that you want them changed as they are not fit for purpose or of merchantable quality.

bro'

CJ, and MickLimk see the response I received direct from the collector manufacturer

''this is a phenomenon which is existing already a long time in this industry. The problem has to do with the ventilation of the collector.

Your case is now a very typical case because as you can see on the pictures, that the ventilation on the outside collectors is good enough which is clear because they have better ventilation when they are mounted at the border, while the ventilation of the collectors which are mounted in the middle is not so good.

The effect, that condensation will appear can be avoided by drilling more ventilation holes in the collector, which I would not recommend because you would loose efficiency afterwords.

The explanation, why the third collector has more condensation than the second one, is that the condensation gets usually more the higher the temperature difference and the temperature difference is the highest at the end (last collector). Due to the fact that the last one is again mounted at the border this is not becoming as obvious as with the third collector.''

They have offered vent caps to be installed if i want to increase ventilation but this would impact efficiency otherwise i leave as is!

I need to supply them the flow and return temperatures on a good sunny day [rare at moment] so they can review system operating efficiency.