Dillsue

+1 to what Joth is saying As the installer is offering to remedy all the defects, if you go down the legal route the only winner will be your solicitors. Hopefully if MCS get involved they can ensure that any remedial works are done to the best standards

In a previous post you quoted an email from the old installer where he inferred there was an RCD. Now he says they dont fit them. Bit confusing if not a complete u turn?? The wiring regs are BS7671. He's admitting theres a string not connected so you probably want to ask the new installer to find out how many panels are on the unconnected string and ask the old installer to pay you for a proportion of the lost generation! If the cables are just hanging without plugs then thats potentially a very hazardous issue as a potential for a shock or starting a fire. If he's keen to remedy that he's probably realised hes likely gonna get a reaming from MCS. If you can get some photos of the unconnected cables its probably worth passing those to MCS

From what youve told us youve got 2 experienced and presumed competant people that cant even agree if theres an RCD fitted to the solar circuit. An RCD is a readily identifiable common safety component so one of these two isnt competant. They can be built into an inverter but as solar installers they should both know that.

Youve got a number of contentious issues where both installers have differing views. Youve also got a few defects identified by the new installer that the original installer has accepted. There's no absolute guarantee that the new installer is competant/trustworthy but out of the pair of them he'd definitely be the one Id be inclined to trust over the other

Ask MCS if they want to inspect the suspected defects and/or supervise remedial works. If they do, then don't let anyone touch anything until MCS have taken the lead on what they want to do. If MCS arent interested then youve little option but to let the original supplier carry out remedial works of their choosing, and potentially loose any "evidence" of poor work. Alternatively you can pay someone else more trusted to determine any remedial works and then do the work. You're unlikely to be able to recover any extra cash you spend if youve denied the original installer the opportunity to fix things!! Do you know what the MCS complaints process says they will do??

A couple of years standing charge would cover the cost of a beefier SWA so a second supply might not be that economic??

You'll not know for sure if any grid upgrades are required, paid for or not, until you ask. Our DNO gave informal approval within a few days of contacting them with a G99 to formalise things. New transformer goes in on Thursday not far off a year after first contact!! I'm not paying so hard to complain. We're at the end of a few miles of 33kv overhead lines and it was our puny transformer that was the problem, not the cabled supply to it so being rural doesnt necessarily mean problems

Yes. I'm sure theres folk on here that have said their DNO has given permission for 5kw export without batting an eyelid??

G100 is in addition to G99 so you apply for G99 and if you or your DNO want to limit export you have a G100 application as a supplement to the G99. That's the way that our DNO does things which I beleive is the same across the UK. Certainly for us, G100 means you must use a professional installer who can set up the limitation with factory/engineer passwords to prevent the user altering the settings. It also means your DNO will want to witness the limitation at a cost of several hundred pounds. Not really DIYable with G100. If you want to add AC coupled batteries best speaking to your DNO to see if theyll accept 2 x 3.68kw. If not maybe replace your existing inverter with the hybrid unit so the inverter limits total export from batteties and PV to 3.68kw If your SWA is the right size/spec you can move the the inverter to wherever the batteries are and bring the DC from the PV through the SWA.

You can have as many immersions and heating coils as you can physically fit in the cylinder. You need to work out the sources of heat you want and how much hot water you need before you tell your installer which cylinder to go for. I beleive you can get 2 channel PV diverters that will power 1 immersion until that cuts out and then switch to second immersion until that cuts out. If you want to maximise PV self use for water heating then get a cylinder with an immersion near the top and a second immersion at the bottom. Have a fast recovery/high efficiency coil fitted somewhere in the middle that will be compatible with a heat pump but can be used with your gas boiler. Speak to a cylinder manufacturer and they will guide you on sizes/capacities/positions. If youve got the space get an extra inch or two of insulation to help keep the heat where you want it. There's a copper cylinder manufacturer in Newark that I found very helpful when we had a custom cylinder built

Ignore the pair of them and get MCS involved. I'd be fairly confident they will advise on any and all remedial work that needs to be done and likely ensure that Mr forceful gets things done to MCS instructions or pays for someone else to sort it out for you. The only place Mr Forceful should be living up to his name is with his staff IF they are taking the p. As a lay customer, you shouldn't even be aware thats his character.

I sympathise with the hassle youre having but don't waste your time with NICEIC as they're not the horse for this course. A complaint to MCS is the route you need to be taking as all the issues youve got will be dealt with by them. As youve now got 2 'professionals' arguing over whats right and whats wrong, you dont want to be piggy in the middle so a prompt complaint to MCS should get some expert help on your side

The architect is echoing whats in the Arostor manual!!!

A2A cant heat your DHW but you don't necessarily need a cylinder with A2A as you can have instantaneous water heaters. From the Architects comments you posted, I read it that the architect is saying the vents need to go outside, not the Arostor itself!!!

If you put the Arostor outside youll have big losses year round particularly in the winter as the cylinder isnt particularly well insulated. What's the Architects rationale for putting it outside when theres a ducting kit available for the heat pump?? Any cylinder with an immersion can work with an Eddi. If you are looking to ditch gas, how will you heat the house then?? Aside from A2AHP, whatever you heat with will likely be able to heat the hot water so are you sure you want the expense and complexity of a heat pump dedicated to just DHW??

How are heating the house?

If the heat and hot water cylinders 'work' with the agile tariff then that would be quite a complex controller that can access the published half hourly rates and run the heat pump whenever youve configured it to run. Is that what it does? If thats a 3rd party controller then it will likely work with any DHW cylinder The Arostor stores hot water like any DHW store. It would need a colossally big heat pump to supply hot water on demand without storing any hot water. When you talk about COP and the Arostor being within your house remember that if you dont duct the heat pump to outside, all the heat put into the store will have to come from within the house which will cool the house.

They stopped our FIT payments a few years ago due to an admin error when they lost the record of a FIT meter inspection. Despite the inspector confirming the inspection and SP verbally confirming the inspection had taken place, they didn't reinstate the payments until an OFGEM complaint hit their inbox. Unbelievably disorganised but I think they got a slap from OFGEM for it. Surprised theyre still s**t but if its the same office handling SEG as it is that handle FIT, I can understand theres still problems!

The ASHP and immersion will likely work separately from each other and it looks like your ASHP set point temp is 48 degrees and the thermostat in the immersion is set to around 55 degrees. If your ASHP heats the tank to 48 degrees the immersion will always try and heat to 55 degrees, if theres power available. If your priority has now changed to export rather than divert then you need to turn the immersion stat down to just under 48 degrees to stop divert into hot water, or bin the solic!

If youre not confident on a ladder, or dont have one, pay a roofer/handyman to cover them up in turn with a sheet of cardboard cable tied to a roofing batten while you check the generation. Assuming it's not a bungalow, its gonna be quite a challenge to hold a sail steady on the end of a long pole while the monitoring updates

With a typical PV diverter as soon as the thermostat in the immersion opens the diverter cant push any more electricity into the immersion and the excess starts to go to the grid. If you want more export at the expense of hot water then either turn the thermostat down or turn the diverter off. Just be concious of legionella considerations, if that concerns you.

Solaredge do 3 phase batteries and I'd hazard a guess others do too?? http://www.windandsun.co.uk/information/solutions/on-grid-solar-pv-battery-storage-solutions/solaredge-3-phase-storedge™-battery-storage-system.aspx#.Y_Er03SnxxA You might want to try other installers?? The hybrid inverter comment means the inverter can have PV connected and handle battery charging all in one unit.

I beleive the optimisers on each string regulate that strings voltage. You have to have compatible optimisers on each string so they can work together correctly and a minimum number of optimisers to ensure minimum voltages are reached. If youre planning on mixing optimisers, SE produce a compatibilty table that shows which models can go on the same string

Assuming you got an SE3680H or smaller inverter, if you take the cover off youll likely see 2 pairs of terminals for the DC connection. One pair is used and the other is spare. There's also space on the bottom of the inverter for a second pair of MC4 connectors to be fitted so its easy to add a second pair of connectors if you want. If you look at the larger inverters they have 2 pairs of MC4 connectors as standard. I think the rationale is that the smaller inverters can normally be installed with a single string of 25 x optimisers whereas larger inverters need dual strings to get to max capacity. Instead of adding extra connectors to the inverter you can parallel up the strings using an MC4 Y piece or a junction box. If you get a big enough DC isolator you can parallel up there which is how my original 2 string MCS install was done

Yes. Max cable length for a single string is 300m so you'll likely be able to wire a house and nearby garage within that length. You might find it easier to run two strings, one for the house and one for the garage. There's a minimum number of optimisers per string which is 8 or 6 depending on the optimisers youre using- see the optimiser data sheet. We used 6mm 2 core SWA for external wiring from garage to ground array, check the cables DC voltage rating is higher that the SE string max. There's a limit to the inverters DC input so worth checking you're not exceeding that, but I dont think it's double the AC power rating. I did read somewhere recently that the limit had been lifted so definitely worth checking.