jack

You can look at the warranty in those terms, yes, but you can also view it as a measure of confidence in the product. If they fail fast, then they'll need to be replaced one way or the other. Even if the disgruntled home owner has to stump up the extra costs for installation, Enphase will still bear the replacement costs of the unit(s). It's not as though someone will just leave a dead panel up there for 20 years (will they?) Bear in mind that the software that comes with the units lets you look at the per-panel microinverter performance over its lifetime, so it isn't as though a dead microinverter can hide anywhere. Exactly what they use, apparently. A bit of reading, again on the understanding that these are the manufacturer's claims (TL;DR - since the capacitors are run at significantly lower temps than their rating, their lifetime is massively increased): https://enphase.com/sites/default/files/EnphaseElectrolyticCapacitorLife.pdf https://enphase.com/sites/default/files/Electrolytic_Capacitor_Expert_Report.pdf Take it with a grain of salt, but they apparently claim a MTBF of 330 years based on accelerated testing. I did a lot of research at the time and I couldn't find any credible evidence of significant failures of these products. I'll admit it's early days though - these things have only been on the market for 8 years or so, so it's only about now we might expect to start seeing significant numbers of failures..

Down our way (Hampshire/Surrey borders) not much is negotiable at the moment. Looking at what friends have been through recently, you're lucky enough if you can get anyone to even quote, let alone be open to discussing lower prices. I wouldn't negotiate individual trades down much if their initial quote seems reasonable. The last thing you want is someone cutting corners because a couple of unforeseen issues have popped up and they're losing money on the job. Even with a main contractor, I think it's a false economy trying to squeeze every last penny out of them. Negotiate fairly, but leave something on the table for everyone.

Enphase offers a 25 year warranty on their microinverters, They've published various white papers on capacitor life, which I suppose you can take or leave given they have an interest in a particular story. I seem to recall reading somewhere that the design of the units is such that even if the capacitors fail, they still work (presumably at lower efficiency and with significantly more ripple). A cynic might conclude that the capacitors are expected to fail at some point, but the user won't notice the drop in efficiency, so they won't claim on the warranty. Very easy (for us!), but that's because our panels are mounted on frames on our flat roof so can be accessed easily from underneath. Not so easy for more typical roof mounted systems, for sure! It's been a long time since I discussed this with the installer, but I faintly recall that there's another slight advantage in lower light conditions. It's to do with the minimum light that allows string inverters to start operating versus microinverters. I don't recall whether shading is required too, but basically on a cloudy day, there may be periods where the light falling on the panels in a conventional system will not generate enough string voltage for the inverter to start operating. With microinverters, the light level required for operation is slightly lower. We have a fair bit of shading, so they made sense for us anyway.

Also, along the lines of looking to commercial regs, it's worth taking a ruler or tape measure with you and trying out the stairs in public or commercial premises. I seem to recall that I based our numbers roughly on the stairs at the office building where I worked at the time. Agreed. I'd have gone for exactly that if we'd had the space. I do think there's a point where stairs become too flat and you feel like you're wasting energy going sideways. But Ferdinand is right, in my opinion, about generous stairs adding to that subtle feeling of quality. It's the same as generously proportioned hallways and landings.

Worth having the cutters too. They aren't expensive and they do make the job easier.

My mother in law used one of these on her Aga for years. Absolutely stupid design. No whistle, so you had to remember to take it off when it boiled. I, of course, boiled it dry the second time I used it! Also, the first people we know who got an induction hob a few years ago got a fancy kettle to go with it. I believe they've since moved on to a plug-in model. We have one of these. I think it's the appliance I'd fight hardest to keep if we had to choose. Quick cup of tea during an ad? Forgot to do veggies and you need to serve in three mins? I just love the lack of hassle and the absence of another appliance cluttering our worktops.

The kettle thing is hilarious. A company I worked for opened an office in New York. A couple of us went over there for a few weeks to hire and train some people. Went to make a cup of tea first morning there and asked the two current employees where the kettle was. Blank stares. A few seconds passed and one of them twigged "Oh, you mean like a tea kettle? I don't even know where you'd buy one of those". I was surprised to learn that most people in New York apparently don't have a kettle. They have filter coffee or drink coffee they've bought take-away.

I went the same way (wundatrade). From memory, MBC uses 16mm pex-al-pex, and the wundatrade stuff connected directly to that without the need for special adaptors. I did ring the supplier before I ordered to confirm compatibility.

Arrgh! It's all coming back to me!!! I had a series of heated discussions with my wife and our architect about stairs while we were finalising our house design. His original plans had stairs that I thought were too steep. The rise wasn't so bad - 190mm, or something like that - but the going was far shorter than I felt comfortable with. Having lived in a few Victorian houses with narrow, steep stairs (and having slipped on the third last step of one while carrying my 3 month old son - he was fine, my elbow took the impact), I was adamant that our forever home would have comfortable stairs that wouldn't have me worrying about walking down them bleary-eyed in the morning. My architect thought it was all a waste of time, as the stairs he'd planned for us were within regs. My attitude was that the regs were a minimum compromise for safety, not an ideal standard for comfort and safety. With a lot of looking at various international guidelines and commercial regs, we ended up with about 182mm rise and 264mm going. I find this ratio extremely comfortable and never think about my foot placement. I'd have preferred an even lower rise given we presently plan to be here until we kick the bucket, but we had some other constraints on length that meant we couldn't manage this. Our stairs are about 950mm wide, from memory, and that's ample for passing in a domestic situation (assuming cake consumption in the house isn't too high!)

Ah yes, that's another limitation. You can't use a wok (well, not properly - I do like a bit of a shake and a bang on the hob when stir-frying!) I haven't really found a solution to this. We don't make that many stirfrys anyway. Perhaps @TerryE's solution of having induction with a gas ring is a good compromise for those that like their stirfrys?

What brand have you used, and how long ago? We have a 1 year old Siemens and the change in heat is as instantaneous as gas on ours. You change the setting and the temperature changes immediately. What size have you used? The large "ring" on ours is 24cm. I just made 7L of yoghurt (don't laugh) tonight in a 9L saucepan. The base of the saucepan is about the same of the ring. Our hob also has two adjacent square sections that can be controlled independently or together to give something like a 20 x 40 cm area. I have a cast iron plate that we use on that for bulk bacon, steak etc (I put it on a silicon mat to prevent scratching). Agree with all that. We have a hand-me-down Le Cruset casserole dish from my wife's grandmother. It works brilliantly, but we now have a permanent mark on the glass where the dish was taken out of the oven and placed on the hob temporarily. There're also fine scratches already showing along the edge of the shallow bevel along the front edge. Oh, and we found a chip along the front edge a couple of months after moving in. No idea who did it - theory is that one of the kids dropped a heavy glass and either hasn't said anything or didn't notice. Might have been me or my wife I suppose. Siliconed the chip in back in place, but I can still see it. In our house, the hob is on our island, so front and centre for all visitors. I wouldn't want a big chunky (and possibly crusty) hob in the middle of an island. That said, black glass does tend to show every mark and splash, so you do need to clean them pretty much after every use. Takes about 20 seconds though, so no big issue. I used to hate cleaning our gas hob because it was so fiddly (and I'm a messy cook, so it needed a lot of cleaning). One thing I do prefer about gas is the ability to agitate food in the saucepans while it's cooking, like flicking a frying pan with your wrist to mix things above a gas flame. You can't do that as easily on an induction hob because you risk scratching the surface, plus it turns off as soon as the pan is picked up. Induction certainly isn't perfect, but having had several gas and electric hobs in the past, I'd never go back.

All you need to understand is that when you heat something like ice, it takes a certain amount of energy to change its temperature by 1 degree (say from -10 deg C to -9 deg C). The amount of energy required for each degree temperature change is fairly consistent. However, once you reach 0 deg C - the temperature where the ice melts - something interesting happens: the ice stays at the same temperature as you keep putting energy in. You keep pouring lots of energy in, and slowly the ice turns into water, but without actually changing temperature. As Terry said above, it takes the same amount of energy to change the temperature of ice from -58C to 0C as it does to convert all the ice to water without changing its temperature. The Sunamp phase change materials use the same principle. The main difference is that they are selected to have a phase change temperature that is adapted to the desired application. In the Sunamp case, the temperature is around 60 deg C (I believe - it may actually be a temperature range more than a specific temperature). That means that when you first heat the material, it'll get to 60 degrees, then stay at the same temp while you pile more energy in. In this way, it can store a lot more energy than water over the same temperature range (incoming cold water temperature up to a safe maximum of, say 80C), because the phase change system has its phase change temperature in the working range of the fluid. The phase change temperature is also high enough that it can usefully heat water above the desired temperature for supply to the DHW side of the plumbing. Having a phase change material with a phase change at, say, 35 deg wouldn't be much use. It's really interesting stuff. I looked at PCM panels when we first started planning the house. They're supposed to help buffer heat to keep the house temperature more constant, but I think they're overkill (and expensive) in a passiv-ish house.

Maybe there's an advantage to charging or discharging sequentially - something like the series PCM equivalent of maintaining stratification in a thermal store?

I've had a devil of a time in the past finding large-bore flexis (particularly for our ASHP). I know there's not such thing as true "full-bore", but what's described as such is often so far off the mark as to be ridiculous if not a flat-out lie.

I believe you have something similar to us (Dualflo, the trade version of the Harvey softener). When I looked at the "22mm full bore" connections, I was surprised to see that they included a pair of flexis with 11mm internal diameter at both ends. Given it was advertised as "full bore", I talked to the plumber (he wasn't onsite at the time) and he seemed surprised at the 11mm restrictions. So I called the supplier and explained in detail, saying that I assume we'd accidentally been supplied flexis for the smaller unit that they do. The new ones arrive and they're the same as the old ones - that's actually the "full bore" flexi they supply! The next interaction is with our angry plumber, who's been told by the supplier that since the cables weren't incorrect, they're charging him for the new ones and he plans to pass the costs on to us! We got it sorted out in the end, but I found the whole thing a bit surprising. We have four showers and two baths in our house. While baths are very rarely used (handful of times a year) and never while the shower is on, two showers running is pretty common, plus there are toilets to flush, a washing machine and a dishwasher that all might demand water at any given time. It seemed crazy that they'd spent all this time and energy running 22mm pipework all over the place, only to send it through four 11mm orifices. In the end, I just had the plumber bin the flexis and convert to 22mm pipework. Also, remember that the softener needs access to a drain, and a power source unless it's one of those that doesn't need one. Hopefully not too off topic...

Sounds good. Just make sure that the lights they specify are going to be generic enough that you'll be able to buy them - or something similar - directly. The brief experience I had involved the specification of a single light (well, a cluster of light types) that would have cost several thousand pounds for a single room, and had no obvious affordable alternative.

Welcome John

We have a one year old Siemens oven with self-clean function. It does indeed give off unpleasant odours when cleaning itself. I tend to do it with the MVHR on boost, and when we don't plan to be sitting in the kitchen. Hopefully this isn't as bad as a wood fire for particulates! I also agree with whoever above said that you need to clean doors etc before running the cycle. We managed to generate some baked-on stains on the door surrounds that will probably take steel wool to remove.

I'm convinced it's an attention span thing. I can focus on a single boring task for hours if I have to but my missus just can't do it. Interesting your wife noticed the improvement in the doors @JSHarris. That seems to suggest that she was actually aware she was doing a poor job!

As did we! There was nothing in the instructions about this, so I called the manufacturer just to confirm softened water was okay before the plumber plumbed it in. They left me on hold while they spoke to their tech department. The answer (best I recall) was something like "We don't recommend the use of softened water because the boiler hasn't been tested with it. We suspect it would be okay but you won't be covered by our warranty if you supply it with softened water".

We talked this through with our electrician and he mentioned the "accessible" requirement. In the end we mounted them in a bank out of (direct) sight on our pantry wall. In our case it was probably the easiest place to put them in terms of cable runs, because it's inline with the more direct route from the CU and roughly central for all the appliances.

This has come up in the past, so I won't beat it to death again, but: - the amount of sodium in softened water will depend on how hard the water was to begin with. Harder water = more sodium when softened. - it's not appropriate to compare the sodium content of softened water with that of milk, because sodium alone is not the whole story. It's the balance between dietary sodium and potassium that's potentially a problem for those who are sensitive to sodium. Milk has three times as much potassium as sodium (470mg/l Na v 1440mg/l K), so the sodium in milk can largely be ignored (indeed, the additional potassium may even help balance out excess sodium from other dietary sources) That said, the risks of consuming sodium have largely been debunked: https://www.scientificamerican.com/article/its-time-to-end-the-war-on-salt/ I personally have no problem drinking softened water. I occasionally drink from our bathroom tap overnight and it tastes perfectly fine. For reference, our tap water is "slightly hard" at 140mg/l CaCO3. Do check with your appliance suppliers. We were surprised and a bit annoyed to learn that our boiling water tap supplier wouldn't guarantee the boiler if used with softened water. While I was sure it would be fine, I prefer not to go against manufacturer recommendations with this sort of thing, so unsoftened it is. After a year, we've had a little bit of scale build up on the outlet, but nothing serious.

Agree with all that. I don't think anyone's suggesting that a 300L TS is going to be a high performing solution if only heated to just above the required outlet temperature. My point is really just that when sized and heated appropriately the temperature fall-off isn't as severe as very simple modelling might suggest.

These TS graphs always seem a little over-simplified to me. Ignoring the full contents of the coil at the full temp of the TS (easily a couple of litres depending on length/internal diameter) cold water coming in at the bottom is heated as it moves along the coil. The water will gradually gain heat as it moves along the coil, so you end up with a gradient of heat along the coil's length. Initially, full temp may be reached well before the water reaches the end of the coil. In that case, the outlet temperature won't drop at all until enough energy has been removed that the water needs the full length of the coil to get to the initial temp of the TS (ignoring losses for this analysis). The outlet temperature will start to fall at that point. Due to this mechanism, the bottom of the TS is cooled faster than the top, resulting in a temperature gradient along the full height of the TS (ignoring mixing at the moment). This means that although the average temp of water within the TS will fall at a particular rate given the length of the coil and temp differences, it will be warmer than that average at the top, and cooler at the bottom. This means that the water at the outlet will be higher than the average temp of the TS at all times. I don't know how you'd model all of that in practice, but the short version is that TS performance isn't quite as bad as might be concluded based on modelling that doesn't take into account the generation of a temperature gradient as heat is extracted. I believe this is one of the reasons that tall, narrow TSs are preferred.

Yes, I saw the other conversation. That was what prompted me to do a bit more research (well, that and yet more prodding from the missus). I'm just not happy with the risk. I have a couple of other ideas that I'm happier with.