Dillsue

Assuming the HP came with a new build 2 years ago then it will likely have a controller or app that will display COP or SCOP. Have a look at the user manual and find the COP/SCOP. Once you've found that value look up the HPs data sheet and compare your value to the values in the data sheet. If you've got a value near the top of the range(higher value is better) then you're doing OK and you'll have to teach yourself alot to improve things for what may only ever be a small gain/saving. If youre lower down the range then the gains/savings may be greater and worth your while reading up on HP efficiency so you can assess your system and make changes. Finding out your COP/SCOP is the first step.

Have a read of the FIT guidance for generators so you get your set up correct. Adding an AC coupled battery between the generation meter and your consumer unit/incoming supply is likely acceptable. The guidance will also tell you if the change has to be notified to your FIt payer, which lots of things do have to be notified. If your FIL already has a 4kw system he'll need to get consent from his DNO to add any more potential export such as a battery. Don't be put off by the red tape as its all straight forward once you understand the constraints.......no one want to loose early FIT payments:)

What the installer feels is appropriate should be based on what you told them you want......did you get what you wanted originally and your lifestyle has changed that you need/want to change things 2 years down the road??

Thanks for the code and enjoy the ££:) Can't beleive they let you withdraw the credit as soon as it's there.

We're almost there......good things come to those who wait Anyone had any problems with Axle restoring original inverter settings after them taking control to force discharge?

£10 grand?? 16kwh fogstar battery £1850 on ebay Solis 5kw hybrid inverter incl meter, battery cables and WiFi dongle £700 Install £500-1000. Maybe less with cables already in place??

Our inverter has a backup feature and I'd like to keep a minimum SOC to cover a few hours backup use from the battery, but not alot if Axle want it:)

Is the Octopus payment via agile outgoing??

So do they pay for solar export on top of battery discharge if its running through the smart meter?? Their FAQs say they need access to your inverter for metering even if you are manually triggering battery export?

Your battery inverter will likely need a meter on the incoming house supply and you may need one to monitor solar generation if you want to charge your batteries off PV. A typical meter connects to the inverter over RS485 comms which will almost certainly work over your cat6 cable. Our meter is connected to the inverter over a 25m run of cat5. Power cabling has been discussed earlier but get your spark to confirm reuse of the SWA.

Sounds like a goer:) Can you limit or fix how much they take from the battery?

I took it that @andeh was looking to put the battery in the garage and inverter in the house hence the query over comms between the 2. Probably doable but would need some hefty cables between the 2

For anyone signed up to Axle, how's the service going?

The comms between our solis inverter and the fogstar batteries is over CAN bus. The cable came with the inverter. I'm sure you'll be able to run CAN over a cat 6 cable with the correct connectors, but.... If you want to use your cat 6 to link the battery and inverter then aren't you going to run into the issue discussed up thread of needing massive cables between the inverter and battery if you have them separate??

A follow up on this thread. I bought a fogstar 16kwh DIY kit and Solis 5kw hybrid inverter back in March. Inverter installed and set up fine but the inverter I bought needs a DC supply to operate so without a battery or generating PV it's dead. With a faulty battery that becomes a problem leading me on to..... Fogstar kit went together OK following 3rd party YouTube videos.....the Fogstar documentation isn't the best. I had problems balance charging and after a couple of weeks Fogstar tech agreed I could build and use the battery. Had problems with a couple of cells which Fogstar were reluctant to replace and accounted for the struggle to balance charge them. Not long after I started using the battery there were a couple of instances of the battery collapsing and dropping to 0% charge in front of my eyes. After weeks of back and forth with Fogstar tech and stripping the pack for balance charging a further 2 times, Fogstar took the battery back for 'test and proper set up'. 3 weeks later I got the battery back and 2 days later it collapsed again so went back for a refund. In the months I had the battery Fogstar stopped selling the kits and the cells that go in them so I guess I wasn't the only one with problems. Spoke an installer who sells Fogstar kit on ebay and he convinced me the product is good so I bought a factory assembled battery through him and it's run perfectly for the last 2 months. There's another one on the way to help with the winter load. I'm happy to recommend fogstar kit but just be aware that after sales can be lacking!

You've 2 options really......get the wireless kit and prove it works before you complete the wiring or install the cabling for wired sensors. It's likely gonna make a mess if you go with wireless, it doesn't work and you have to retro fit the cabling. You could leave the cable buried in the wall and try the wireless kit with the cable available as a backup

I assume the "50 degrees/auto adaptive" is 50 degree DHW set point and auto adaptive for the space heating(CH)?? So if it's not tripped for a few days, is the DHW up to 50 degrees and reheating as you use it ie things are normal??

The immersion may or may not be faulty but theres likely another fault as the HP should be able to heat the DHW way beyond 20 degrees without needing the immersion....there's no point in having the heat pump if it's going to default to using the immersion!

The 3 modes you mention can all likely run without a stat but your installer may still have put one or more in. Have you got multiple stats suggesting you've got zoned heating? This is unlikely to be relevant whilst you are trying to get the DHW sorted. In your first post you say the system started with this issue soon after installation?? Did the installer not sort it out then, or try to??

OP says "it doesn't heat the hot water either" so I assumed it's CH and DHW??

Can you alter the hot water schedule to come on during the day when you can watch what happens when it tries to heat the hot water? There Should be little need for space heating just now so I would focus on getting the hot water up and running. Do you know what the "stats" do as you shouldnt need them if running in auto adaptive mode. If you're really under pressure to get this sorted I would contact any local Heat Geek engineers and see if they have Ecodan experience and can help out.

Pretty sure that's not the case....desirable maybe but far from essential. I sold my late parents house a few years ago and the buyer(likely buyers solicitor) asked for gas cert, elec cert, this cert,that cert and all manner of things. I just said none were available and the sale went through.

Pump anti seize is enabled. I can't remember exactly how often it operates but the couple of minutes a week rings a bell.

After installing our HP a year ago and it running well throughout last winter, I thought Id run it up over the weekend after a few months shutdown. It started and ran fine and I shut it down after a few hours then went to check the magnetic filter. Found the filter with quite a bit of flaky debris stuck to the magnetic tube. I don't know whether the debris accumulated through last winter or came from the weekends test run. There was more debris this time than any of the half dozen filter cleans/checks I did in the weeks after installation last year, so glad I checked it. After getting only minimal debris in the weeks after install, I was quite surprised how much flaky grot was in there! Our system is 90% rads so maybe we're going to see more debris than an UFH system, even with inhibitor, but worth checking any filters in your system to make sure they're clear.

A quirk of the Vailant design/software then??