Hi Mars, once received the visit and once received the quotation I will surely update you.

Air to water systems are surely kinda popular in Italy right now , however I've got to highlight that after a big growth depending on a, too big, state bonus now w will see a decrease in number of installations. Anyway new homes always have air to water heat pumps installed and if a renovation is planned in fifty percent of the cases a heat pump will be planned to subsistute the existing methane system.

@alecsej They are installing their own Aira machine. I questioned why they had the odd Valliant image on their website as it was a little confusing. They said they used to fit more Valliant units, they still fit them but now only if a customer specifically requests one. 

Thanks Mike. As I said they are my biggest hope cause of the dimensions of the internal unit. What kind of internal unit are they going to install the 100 liters or 250?

@alecsej it's the 250 litre cylinder with the 40 litre buffer. I'll upload some photos next week all being well.

Update from install day 1. The Aira team arrived promptly at 8am with 2 heating engineers, an electrician and the delivery truck full of all the hardware. All were in nice yellow Aira vans and branded uniforms. They unloaded as quickly as they could after we moved a few cars around on our tight Victorian street. I took the morning off just to make sure I could answer any questions we both may have. I think this was really useful and might be a good recommendation they could make to future customers. The team have been very friendly and professional. At the end of day one, some of the team headed off at 4 but one stayed until 7pm working and tidying up. They have hung 5 of the 6 Radiators but 2 are not quite fulling connected yet. 1 radiator required sections of carpet and floorboards to be lifted and have been replace neatly. Other radiator have tricky pipes coming through existing floor tiles, so external pipes were needed to extend the pipe to the new width of the radiators. The Heating circuit of the boiler has been disconnected which is fine as it nice and warm and we still have hot water from the boiler. The Electrician has fitted a new dedicated consumer unit for the heat pump in the cellar and has spent the day chasing cables and conduit from the cellar, out along my outside wall on my neighbours side. He will be ready to drill through into the utility room at other end of the house, where the cylinder will be located tomorrow. The team were back at the house 8am this morning before I set off for work, I will give you a progress report from the end of day 2 soon.           

Update from end of install day 2. Lots of holes drilled today. large pipework holes drilled through the outside wall and through the internal wall of the downstairs toilet that the pipe will run through on the way to the utility room/cylinder location. Electrician has drilled trough to finish getting cables into the utility room to complete his cable run. Looking neat and tidy down the side of the building. He even tidied up existing conduit that was inferior to his, so they all run parallel. A concrete base has been laid and a grey slate soakaway created to match the colour of the heat pump, which is a nice touch. The concrete is touch dry so may be ready to sit the heat pump on by the morning.  A fair amount of primary pipework has been completed around where the cylinder will be located. Progress looks great and I wouldn't be surprised if both heat pump and cylinder are in place and piped together by end of day 3 tomorrow. The electrician is due back on Thursday (Day 4) so we wont be firing it all up before then.    

Thanks for the updates MikeH. If the Italian services works like the UK service I might bet on Aira. Let's see what the quotation is going to be, still a couple of weeks away.

Update from end of install day 3. The heat pump and cylinder are now in position and piped together through the wall and through my downstairs toilet. The buffer tank, pump and expansion vessel are in place. The buffer tank pipework isn't yet completed and the last radiator needs pipes running to it. They expect to start commissioning the system tomorrow by lunch time depending on how the electrician get on wiring up both internal and external units. I was wasn't expecting the cylinder to be placed sideways but space would not allow for it to face outwards. They needed to take the internal door off just to get it in and work on it. The cylinder has no display so it's not a big deal and I've been assured all parts that would be serviceable are in the top section and are accessible. Really happy with how the external heat pump is looking now it's in place.

Update from end of install day 4. The boiler has been removed from the loft and the heat pump is working. After a little head scratching, we managed to paired my phone/app and the wi-fi to the heat pump and set up what few setting are in the app to play with. They make a lot of their intelligent software that's supposed to make the system hassle free. I guess this is great for regular users who just want the heating to work with little fuss. But not the best for a geek, as you can't control the time the heat pump generates hot water and you can't see the SCOP anywhere I can see. Hopefully they can release an advance mode that can give you more data and more control in time.

The big issue that I have only been made aware of today is that Aira haven't provided the wireless thermostat for the house. The engineer can't provide a timeframe for when we will get this, as they haven't started manufacturing them yet! I can't quite believe they haven't mentioned this until now. It was late in the day and we only had time to ensure hot water was working correctly. One engineer is coming back to lag the pipes and clean up tomorrow but I am not sure if they can force the system to provide heat to the house to test the radiators. But I really want them to make sure the heating properly works and the radiators are correctly balanced before I sign the job off tomorrow. The engineer says the outside temperature sensor will call for heat when it drops cold outside but this is not the level of control we need. I know we don't need heating for another month but I'd liked to have known this was not going to be provided and an ETA for this part, before I had agreed an install.        

@mikeh That is a great shame - especially after everything was going so well. It does sound as though Aira would like to say ‘Leave it all to us, we know best’ A bit of a bummer if that is their attitude though. 😧 Toodles.

@mikeh Don't sign off until everything is done correctly!

@mikeh Thanks for the latest update, which is helpful as my finger is hovering over the button to accept an Aira quote. 

Can I ask, is there a way for you, the customer, to optimise the weather compensation settings?

If I understand right, if they have designed your system with a flow temp of (say) 45C, it will be capable of producing this temperature when the outside temperature is at design temperature: say -2C. But if the outside temp is, say, 7C, the heat loss will be lower, so the ASHP will be programmed to produce a lower flow temp: say, 40C. And so on for other outdoor temperatures.

However, this is all based on educated guesses about the actual heat loss and how it varies with outdoor temps. So, if the programmed flow temps turn out to be hotter than needed to compensate for the actual heat loss, the ASHP will cycle on and off, which is less efficient than operating continuously at exactly the right flow temp to balance the heat loss. So, ideally, the programmed flow temps should be tweaked based on actual experience, to optimise efficiency.  

Is there a way for the customer to make these adjustments? I'm guessing not. Or does Aira's system do this itself?