jack

Yes, but the combination needs to be inventive. Adding, say, a lock to an enclosure isn't ever likely to be inventive given how ubiquitous the principle is.

The international search report says that only claims 9, 10, 29, 31, 34-36 are novel, and concludes that none of those involves an inventive step. From a quick look, I don't even think all of the supposedly novel claims are actually novel. For example, "novel" claim 29 merely defines the step of removing an existing hot water cylinder from a domestic building. That doesn't sound very novel to me.

I've done some digging (well, no-digging) too, but when I'm avoiding work, I tend to do so at my desk. It feels less like I'm shirking than if I went out and did what I actually want to do!

I think even the RHS is slowly starting to come around to the idea that destroying soil structure by repeatedly digging over is counter productive. I've wasted far too many hours watching Charles Dowding talk about no-dig methods on YouTube. He has an incredibly relaxing presentation manner.

@mistake_not @marshian This is the image (I also added it back to the first post):

Not visible on my phone, so I think you're right. I'll post it again tomorrow when I'm back at my desk.

That's odd. It's visible to me in both my post and where you quoted it in your reply.

I get all sorts of headaches with dry air - same in winter when we have cold, dry periods. It's all sinus related.

No, that's accurate. Bedrooms are cool but acceptable (to me if not my wife!) in winter. This is the upstairs hall temperature in January and February (lowest is 17.4 °C, highest is 20.3 °C): I'll be tweaking the control loop for next winter to see what sort of impact I can have on the lowest temps, as I now have more info available to let me analyse what's going on. If I were doing this all again, I'd consider tiling upstairs with a wet UFH system. Rugs down in winter for underfoot warmth, along with intermittent mild heating to keep the temp relatively stable. Rugs up in summer, with cooling as needed.

Panasonic are an option. It's been over 10 years since I installed mine, but their technical support department was happy to take my phone calls to troubleshoot our installation, which I doubt all companies would be happy to do. I remember we were getting an intermittent error that we couldn't find the source of. They suggested a slight change to something like flow rate and the problem disappeared. Even as a pleb, you used to be able to get a login to the Panasonic Pro website, which gave access to all their technical docs that aren't publicly available. Again, this info is long out of date, but I did a comparison between the Panasonic 5 kW model I eventually bought, and a Nibe 8 kW model. As you know, the power ratings are somewhat nominal, but I didn't expect the comparison to look like this: One thing I'm not sure about is conditions under which the ratings are determined. For example, periods of low single digit temperatures when it's damp (common in many parts of the UK during winter), defrost cycles can have a significant impact on COP. A couple of other things I'd consider are: What sort of functionality you get without requiring cloud access. Surface area of heat exchanger. If you can find a low power unit with a larger heat exchanger, my guess is that it's likely to require fewer defrosting cycles in cold weather. I'm sure someone (maybe @JohnMo) has mentioned that some ASHPs have some sort of two-stage system that can operate very efficiently at lower power on one stage, then bring the other in when high power is required (e.g., DHW heating). Can't remember whether it's dual compressors or something else. I imagine this sort of tech is more likely to be available in higher power units.

I spent many years working air-conditioned offices in Australia. The dry air and cold drafts aren't something I found very pleasant. By contrast, underfloor cooling feels very natural.

I only started running Grafana earlier this year, so the only data I currently have are Loxone native (and hence probably not much help). For context, I presently run the cooling open loop. I can enable cheap rate cooling and/or daytime cooling (scheduled between 10:00 and 16:00, from memory). I can also push a button and get 2, 4, 6, or 8 hours of cooling. Periods where the cooling doesn't come on for a period are usually cooler and/or cloudy (and hence less solar gain) periods. This shows the downstairs slab temp (note: not air temp) and the UFH flow temp for June and July last year: Note the runup to the peak slab temperature in late June. With the cooling off, the temperature rose consistently from 19.4 on Monday 23 June to 21.6 on Saturday 28 June, when I enabled cooling This is what the weather was doing during June 2025: The house has a long time constant when it comes to reacting to external temperatures. Even though the temperature in June was highest on about 21 June and fell off sharply after that, the internal house temperature continued rising for a couple of days before I turned the cooling back on. Unsurprisingly, the cooling downstairs has virtually no impact on upstairs temperatures. Here's 10 days starting on 23 June, showing the relentless increase in upstairs temperature even after the cooling is turned on downstairs on the Saturday: That was actually the hottest it got upstairs in all of 2025. Not sure if any of that helps. I originally planned to add things like flow sensors along with power monitoring for the ASHP so I could get a better sense of what was going on an perhaps tweak things for better performance and lower costs, but in the end I decided it was too expensive and complex. That said, earlier this year I expanded the inputs available for Loxone, such as excess solar power and temperature forecasts. I'm hoping to do something with those to better automate cooling this year.

I can only talk about my personal experience, but we cool our downstairs slab with an ASHP during hot periods and it's remarkably effective. Coming in from outside on a hot day is like walking into a cool cave. We run a flow temp of about 16 °C and that's enough to keep the slab under about 20 °C, even in a multi-day heat wave. We do have concrete floors, which I'm sure helps a lot. I don't imagine the effect would be as powerful with, e.g., wooden floors. I'd be careful about overstating the effects of convection in a well-insulated house using low flow temperatures. Sure downstairs gets warm, but as you walk up the stairs there's a clear temperature gradient as you move towards the downstairs ceiling. In the middle of winter, it's typically 2-3 °C cooler in the hallway upstairs (no heating upstairs) than it is downstairs, even in the central landing with open stairs and a large double height area. I suspect that hotter floors in a more poorly insulated house would increase convection.

This is a useful thread:

You have a sense of humour, I'll give you that.