Poor Solar PV Installation ??? Expert Help Needed

[Bucks]

Hi guys,

I am new to the forum & am hoping for a bit of help & advice on the issue described below, before I get in touch with the installer.

Sorry but if you bare with me I will spread the situation over 6 posts, then add a few photos (I can't add photos until I have made 6 posts)

 

[Bucks]

We have just had a 3.92kw solar pv system installed on our SW facing roofs, 12 panels on the main roof which is two storey & 4 panels on our dining room roof which is one storey and is shaded by the main house in the morning.

The panels are Sharp NUR245J5 & inverter is a Fronius IG TL 3.6

 

[Bucks]

I am now concerned that the 4 panels on the dining room roof that are shaded in the morning will be affecting the efficiency of the 12 panels on the main roof,
Sorry I don't know all the technical jargon but as far as I know all the panels are wired together in one string.
Before the installation I asked about the shading issue & the installer said shading wasent an issue but he could wire the 4 on the dining roof in a separate string, but when they came to install the system his colleague said something on the lines of the four panels couldn't be wired separately as there wouldn't be enough power for the inverter and wiring them all together would be fine as the panels have diodes & mentioned something about the christmas tree light scenario.

over the last six days since installation we have generated a total of 18.7kw, but to be fair we have had hardly any sun.

 

[Bucks]

The installer is MCS approved & also a member of REAL

 

[Bucks]

Also someone has pointed out that I have shading issues on the upper roof from the boiler flue, soil pipe & ariel.

 

[Bucks]

Looking through a few of the other threads on this forum other alarm bells are ringing now about the state of the roof membrane, at first I thought this was collateral damage & couldn't be helped, but now I'm not so sure, this all a bit annoying as the whole top roof & membrane was brand new two years ago.

 

[Bucks]

 

[Bucks]

These images of the tears are just a few of many

 

[SolarCity]

Before the installation I asked about the shading issue & the installer said shading wasent an issue but he could wire the 4 on the dining roof in a separate string

Not with the Fronius IG TL 36, he couldn't. You'd need an inverter with dual MPP tracking to do what you are suggesting and you'd need one which had a voltage range low enough to accept a voltage that the panels would produce (without looking too much into it, I'd say the Power One range is a good bet)

but when they came to install the system his colleague said something on the lines of the four panels couldn't be wired separately as there wouldn't be enough power for the inverter and wiring them all together would be fine as the panels have diodes & mentioned something about the christmas tree light scenario. .

The reason they couldn't be wired seperately is due to the poor inverter choice and nothing else. Inverters with one MPP tracker can still have more than one string but they must be strings with an equal number of modules.

The Fronius IG TL 36 can have two strings connected to it but it is unlikely - this is because it cannot cope with higher amperages. This is one of the reasons why the IG TL 36 is generally only suitable for unshaded situations.

 

[Noshocks]

The fronius can be wired as one string as it has a high input voltage, and the other guy is right four modules couldent go on a single string, so it does look like its a single string, however shading is shading and not ideal, the bypass diodes arent going to solve the issue.
Have you got any pictures?

Have just seen the pictures, waste stack should have been sorted, this is a school boy error, as said the PVI-3.6 inverter would have been a better choice.

 

[SolarCity]

The aerials look like the will create shading judging by the fact that you are south west facing. The vent stack will be having a very significant amount of shading. The fact that the panels have been installed like that is, frankly, an utter joke.

All of the damage to the felt membrance is unnecessary and very, very bad workmanship.

 

[SolarCity]

Ask the installer for his opinion. Mention some of the points brought up on this forum and see what he says. Have you paid him yet?

 

[Bucks]

That is why I thought I would try & get some advice on here first before I get in touch with the installer
I have just paid him 20% deposit, I got the invoice for the balance today.

 

[SolarCity]

Not sure where you stand with the poor system design (after all, it's just my opinion)

I'd definitely get them to sort out the vent stack and sort out the weatherproofing on the felt. You ordered an MCS quality installation and shouldn't pay until you get one.

 

[SolarCity]

It is difficult to see how much shading the lower roof area is getting. If it is significant then I'd ask the installer to suggest an alternative inverter.

By my sums, the Sharp 245w panels are a little low on the voltage for the 4-panel string. However, the Power One inverters can be configured to fire at lower voltages so this might be an option (never actually tried it myself)

 

[Bucks]

The lower roof area is shaded from the main house until about midday
Other people have told me that with them being wired into the same string as the other 12 panels, the efficiancy of the 12 top pannels would be greatly reduced.

 

[JD6400]

I would go with what Biggs is saying !
As for the vent pipe we had two neighbouring houses only about three weeks ago with two on each roof , after a quick enquiry with a building a contractor we work closely with on other projects and a double check of what they said with our domestic roofers just to make sure , half hour latter we have four tile vents at about £40 each and the job is looking good !
I may be barking up the wrong tree but do you live in Bucks more specifically Steeple Claydon , your house design does look very similar to some in that area ?

 

[JD6400]

Just looked at the pictures again , now i may be wrong but the block of four are clamped on the their short side , not sure about the 245's but i know that used to void the warranty on the 235's ?

 

[nbown]

you can cut down the soil stack and fit a 4" air emittance valve, that would stop the shading of the top roof. i took mine out completely and removed to boxing in in the bathroom.

Just for reference and it may not help as i'm in Essex. I had my install done on Saturday (not running until Sunday, low light levels) 3.92Kw (all panels on the roof), SSW facing. Fronius IG-tl 3.6 and have produced 43KWh.

Question, what's the darkening on the panels, it appears in the area where the junction box could be on the panels, i'm not saying it's right or wrong, i was just trying to work it out.

 

[Bucks]

I may be barking up the wrong tree but do you live in Bucks more specifically Steeple Claydon , your house design does look very similar to some in that area ?

No I live in North Yorkshire

Question, what's the darkening on the panels, it appears in the area where the junction box could be on the panels, i'm not saying it's right or wrong, i was just trying to work it out.

I dont know what it is

 

[MorganPVI]

we've had 39kwh for the last 6 days, so suspect some shading issues. Very bad desgin as Biggs has said, easily fixed swap out for a Aurora 3.6.

I surveyed a house today, lots of social housing had 10 or 12 of the little Sharps, 15-20 properties, EVERY one had a the long vent pipe at the base of the panels merrily shading away.

 

[Bucks]

THANKS for all your comments so far Guys its much appreciated,
I will have another look through them tomorrow when I get in from work,
no doubt I will have a few more questions.

 

[SolarCity]

By the time you've done a bit more research on this, you'll know more than your installer. The system design and the fact that the vent stacks are left in (which will give almost day long shading) tells me that your installer is not very clued up.

The fact that he has torn holes in the felt (for reasons that escape me) suggests that he couldn't care less either.

 

[funboy57]

The soil vent at the front can be dealt with not sure the same applies to the boiler flue near the ridge.

 

[Scott H]

if I recall correctly, Air Admittance Valves can only be fitted if there is another vent on the stack and the top of the stack must be more than 900mm above the top of any window openings - to prevent the smell coming back into the house.

hope this helps

 

[JulianC]

Air admittance valves can only be fitted if there is an open vent on the same drain - this can be on another property. A (very) basic rule of thumb is if every 5th property has a soil stack, the rest can be fitted with an air admittance valve. In other words, if the next door neighbours have got one, lop it off!

The 900mm above a window opening only applies to soil stacks (that are located withing 3m of a window opening). AA valves, by their nature, can't let smells out. They must be located internally otherwise they freeze up - usually in the loft (or bathroom so long as it isn't boxed in).

 

[Scott H]

thanks for the clarification JulianC, I wasnt aware that you could get away with using a AAV and 'use' your neighbours open vent - I had wrongly assumed it had to be on your system.

 

[JulianC]

No probs. The wife's a plumber so comes in useful occasionally ;-)

 

[Bucks]

Thanks Guys, you have confirmed what I thought about the soil stack regulations,

I don't think I can put a AAV in as it would be so tight to get access with it being right in the eaves, also it would be surrounded in insulation, the soil pipe is all boxed in in the bathroom, so if it can't be boxed in thats not an option.

I am thinking the best option might be to cut the soil pipe right down to just a couple of inches above roof level so it didn't shadow the panels, I know that it wouldn't comply with building regs, but who's to know and I cant realy imagine smells getting in through the windows. I think that would be better than leaving it to shadow the panels.

The ariel could if it had to, be moved to the left hand side of the house, but it would be overhanging next doors flat roof.

Not sure but would it be possible to shorten the boiler flue a bit?

Any comments to these suggestions would be much appreciated.

 

[Bucks]

Just looked at the pictures again , now i may be wrong but the block of four are clamped on the their short side , not sure about the 245's but i know that used to void the warranty on the 235's ?

Just checked the manual & it looks like your right, it pretty much says the panels must be clamped on the long edges with minimum distances from the edges.

It's a pity the installer didn't read the manual!

 

[Bucks]

All of the damage to the felt membrance is unnecessary and very, very bad workmanship.

I'd definitely get them to sort out the vent stack and sort out the weatherproofing on the felt. You ordered an MCS quality installation and shouldn't pay until you get one.

How do you sort out the weatherproofing?
As far as I can see it is a matter of removing the ridge & all the tiles, then re felting & battening it all then re tiling?

 

[Bucks]

You'd need an inverter with dual MPP tracking to do what you are suggesting and you'd need one which had a voltage range low enough to accept a voltage that the panels would produce (without looking too much into it, I'd say the Power One range is a good bet)

Roughly how much more expensive would these dual MPP inverters have been compared to the Fronius IG TL 36, are you talking £10s or £100s or a lot of £100s differance?

All your help is much appreciated

 

[JD6400]

I would get them back and remove some of the bottom row then strip back the tiles and mount a tile vent further up the roof where you can get to it from in the loft , that is if it is OK to use a tile vent ? Which you will need to check with a builder / roofer.
Out of curiosity was it their first install ?

 

[Bucks]

I am wondering if we had a dual MPP inverter, & eliminated the soil pipe & the ariel, is it possible/a good idea to wire the two panels that would be shaded from the boiler flue to the same string as the four lower panels, so that we had the 10 panels with no shading on one string & the 6 panels that are shaded/part shaded in the morning on a separate string?

 

[Bucks]

Out of curiosity was it their first install ?

No they are supposed to have done loads of installs, they have been MCS registered since Aug 2010.

The awkward thing is he actually lives about 10 doors away from us & I pass his house every day, he has installed panels on his own roof, but there are no obstacles on his roof.

I thought I would keep it local, also he has done some work for us over the last couple of years (advice & testing for part P) That's whats realy annoying, I thought I could trust him to do a good job & this is what thanks I get.

 

[Bucks]

I would get them back and remove some of the bottom row then strip back the tiles and mount a tile vent further up the roof where you can get to it from in the loft , that is if it is OK to use a tile vent ? Which you will need to check with a builder / roofer.

Sorry not quite sure what you mean, would that mean that the vent tile would be under the panels, I'm pretty sure that wouldn't be acceptable.

 

[solarsavings]

From your photo's it's quite clear that the nib on the back of the tiles was hard up against the membrane ( the battens are too thin) that would have held the tiles almost as tight as a nail and yet he clearly continued to kick the tile up tearing the membrane is no easy feat :-(

A flat nail bar or a couple of wooden wedges and the tiles would have slid up as he needed them to without catching the membrane.

 

[SolarCity]

How do you sort out the weatherproofing?
As far as I can see it is a matter of removing the ridge & all the tiles, then re felting & battening it all then re tiling?

One of our installers put his foot through a tile and straight through the membrance. We removed a large section of tiles and eased the battens up to remove the nails. We then run a new section of felting across the top of the existing felt (yet under the felt above) covering the damaged area. It took about an hour to put right and we always keep a roll of membrane on the van for this reason. It's not a big job but it should have been done before the panels were installed.

 

[SolarCity]

Roughly how much more expensive would these dual MPP inverters have been compared to the Fronius IG TL 36, are you talking £10s or £100s or a lot of £100s differance?

All your help is much appreciated

It depends. There are dual MPP inverters with a price comparable to the IG TL 36. The Power One 3.6 is in fact slightly cheaper and it has dual MPP tracking.

 

[SolarCity]

I am wondering if we had a dual MPP inverter, & eliminated the soil pipe & the ariel, is it possible/a good idea to wire the two panels that would be shaded from the boiler flue to the same string as the four lower panels, so that we had the 10 panels with no shading on one string & the 6 panels that are shaded/part shaded in the morning on a separate string?

Personally, I would have kept the lower panels on an entirely seperate string and sorted the vent stack out. If you can get the aerial moved then it would be an idea to do so. I don't think the boiler flue will be much of an issue but if it is then you could ask a plumber to move it to the front roof area. Whether this can be done depends on the manufacturers guidelines (the more bends you have in a flue, the shorter the allowed run) and the distance that the flu has already run.

 

[SolarCity]

You should get your installer to sort out the panels which have been mounted on the short sides. This will invalidate the warranty and it will you that is out of pocket if anything goes wrong.

 

[Bucks]

One of our installers put his foot through a tile and straight through the membrance. We removed a large section of tiles and eased the battens up to remove the nails. We then run a new section of felting across the top of the existing felt (yet under the felt above) covering the damaged area. It took about an hour to put right and we always keep a roll of membrane on the van for this reason. It's not a big job but it should have been done before the panels were installed.

This is the whole of the SW facing roofs that have the membrane damaged, not just one area so as far as I can see to put it right, it involves removing all the solar panels removing the ridge & all the tiles, then re felting & battening it all then re tiling then reinstalling the panels, properly this time, A major Job.

 

[Echo]

I wouldn't pay until he has sorted everything out. If he doesn't sort it report to REAL (might be a waste of time) and also his MCS governing body, whether it be NIC, Napit etc.

 

[Bucks]

You should get your installer to sort out the panels which have been mounted on the short sides. This will invalidate the warranty and it will you that is out of pocket if anything goes wrong.

I am hoping to get him to sort everything out, I am just trying to get all the facts & draw up a list of what needs doing before I get in touch with him, as I don't have much confidence in what he would have to say after the way he has done the installation so far.

 

[Bucks]

I wouldn't pay until he has sorted everything out. If he doesn't sort it report to REAL (might be a waste of time) and also his MCS governing body, whether it be NIC, Napit etc.

I'm hoping it won't come to that, but that will be down to whether he is willing to put it all right or not.

 

[Bucks]

I emailed the installer this morning, he & his colleague came round a short while ago full of apologies, they say they will change the inverter so we can have the 4 lower panels on a separate string & sort out the other issues, including getting a roofer in to sort out the roof, so hopefully it will all be sorted soon.

THANKS for all your help & advice its much appreciated, I will keep you informed.

 

[JD6400]

We are only as good as our last job , and putting aside why your one ended up with the issues that it did ?
It is their chance to redeem their selfs , i have to admit i tend to judge a company not on how they preform day to day but more so on how they preform when faced with a cock up / problem , how ever it was created !
So here's hoping it goes well ?

 

[TrickyDicky101]

... i tend to judge a company not on how they preform day to day but more so on how they preform when faced with a cock up / problem , how ever it was created !

Well said and I agree completely! Let's hope the OP's installer will now give the OP the installation he wanted.

 

[Bucks]

The installer has dropped off some info about the new inverter he plans to supply, it is a Eversolar TL4000 which the specs states is single MPP tracking, I note from some of the earlier posts that you state it needs to be dual MPP, so I am still a bit confused / unsure, can anyone please offer any advice on the inverter issue.

 

[Bucks]

I have just had the following email from the installer,

"I have just been onto technical help regarding your inverter as the last thing I want to do is install a inverter that does not perform as predicted. They have informed that there is not currently an inverter that will be suitable by any manufacture. The reason for this is the low voltage that 4 panels produce they would not start the 2nd string.even with a dual tracker. In their opinion and my own it would be a much efficient system if the 4 panels were removed completely as these as you are aware are having a significant reduction in system output. With these removed the 12 panels on the main roof would be running at full efficiency and the system would generate a produce a faster feed in tariff return. We had proposed a eversolar which has a low start up voltage and had 2 strings but double checking with them it will not be suitable either.


So to conclude the best option would be to remove the 4 panels and just have the 12 on the main roof. I understand it is not the 4 kw system you wanted but this has is just not possible with your roof."