jack

Agreed. In fact, there's no reason to even have a bath drain routed throught this sort of unit. You connect the drains of one or two (I believe they recommend no more) showers to it, and connect the outlet of the device to the main drain. That's it.

The rate for ASHP (at least) went up a couple of years ago, from memory.

The heat recovery on these smaller horizontal units tends to be a lot less than on the large vertical units (like this, for example).

Yes, that's what I was told. Bivalent systems require metering for billing purposes. It also used to be the case that the system had to be capable of having metering installed. However, from memory, this was to do with capturing real-world data for research rather than being anything to do with billing/payments. The requirements were something like you needed an accessible straight portion on the flow and return pipes of some length - 500mm, 600mm, something like that. I think they got rid of that requirement when they made changes to the RHI in late 2017.

Not really - the system is really only functional when you have continuous warm water being used, and simultaneous warm water going down the drain. You might get a bit of recovery if you drained the bath while hot water was being used elsewhere, but realistically, it's designed and connected to work when people are having showers. I believe the split system works better because the higher flow of cold water though the device allows more energy to be extracted from the drain water. They're not cheap - maybe £600-1000 depending on model? In our case, we have a very active family who all do sports throughout the week. I sometimes have to shower twice a day, and my wife is the same. Our kids aren't that heavily into the long shower routine at the moment, but I'm sure that's coming. Overall, we foresaw the potential for a lot of heat going down the drain from showers. Even if the payback period is 15 or 20 years, there's an awful lot of energy being saved over that time, which is no bad thing.

Yes, that was the de facto connection standard when I installed mine. I believe our plumber actually talked me into this arrangement instead of the dual connection arrangement (possibly due to pipework complexity - it's been a while, so I can't remember the reasoning).

For the highest recovery, you split the preheated water between the shower and the DHW cold feed. You can just supply it to the shower if connecting to both is difficult for some reason. You can also supply it just to the DHW system, but from memory that's the least-recommended arrangement.

The sieve is clearly for aeration.

19" is width, not depth. You can get different depths of 19" cabinets/racks to suit your needs.

On the subject of frameless glass, my main point would be to make 100% sure that you have every detail worked out, especially drainage (including how you handle any leakage into the channel supporting the glass). I overlooked these details on our (admittedly timberframe) build until too late, and it's added a lot of stress, delay and cost trying to sort something out.

I'm sure there was a discussion year or two about something like this, or maybe I read it elsewhere. Just go for shower waste water heat recovery. While it doesn't save water, a properly installed system will return over 50% of the energy that would otherwise be lost straight down the drain. No moving parts to go wrong, and no need to bathe in your own crap. Win-win.

Yup. And proud.

I adjusted the settings so that only one displays the time. Far easier!

Like you need more kids!

I don't think that's what @LA3222 is saying. The point is just being made that this is a serious topic, and the "you can do it yourself" approach needs some caveats that weren't being expressed by those encouraging a DIY approach. What happens when someone downloads STROMA, makes a couple of apparently minor errors that aren't picked up by building control, and then builds their house? They go to get the as-built SAP done and find no-one will do it cheaply based on their calculations, so actually they haven't saved much - if any - real money. So they pay, and then the errors that they made are discovered. It's too late to fix them now, and since the design SAP wasn't done by a professional, there's no comeback. Potentially thousands of quid in remedial work could well be required for the sake of a couple of hundred quid. And that's for those who value their time at zero - a problem I definitely have (I will regularly spend an hour on the internet trying to save a few quid, when working for the same amount of time would leave me in an order of magnitude better off financially and in terms of stress). I'm all for DIY. I've done a fair bit of it myself (I've even changed brake pads). But I know where my limitations lie, and saving at most a couple of hundred quid at this stage seems like something you'd want to be very certain about before taking it on. Note that I'm not saying "don't do it". I have exactly the same approach, and it's the bane of my bloody existence! I'm all for doing things yourself, but I also believe that there's a balance to be drawn, especially once you weigh up cost versus risk versus delay versus quality versus stress versus the general principle that doing things yourself can be hugely rewarding.

I doubt there's a single member here who hates trained professionals. I don't doubt that many feel some professionals could do with acting a little more, well, professional.

Can't help but post it now - what a tune:

That's the original song, yes. @Nickfromwales has previously posted the clip to a version of the Utah Saints song that samples it. I think it's come up a couple of times actually.

WOW! Kudos for sticking at it. Why four coats? I think we just have a base coat and a top coat, and it looks pretty good in most places.

They didn't. I suspect it was more to make people aware of the potential issue than to act as a calibrating standard. The main issue with typical metal tapes for me is that bit on the end that slides slightly to account for whether the end of the tape is being pushed into, or pulled away from, whatever's being measured. I just always assume there's a couple of mm error and try to make sure that an error of that magnitude doesn't impact what I'm doing. One example is where the absolute measurement isn't as critical as making sure it's replicated properly (ie, precision is more important than accuracy). An example would be making legs for a workbench. Best to cut all legs at once, or at least use the same physical template for each of them. Doesn't matter if they're all 5mm shorter or longer than the design (which is slightly arbitrary), as long as they're the same. There's something called a "story stick" in woodworking that's a nice development of this idea.

I'm sure there was someone, ages ago, who'd set up an onsite test length where visiting trades could test out their tape measures before relying on them for critical measurements.

That's my starting point for trades of any sort around here. Get any sort of company (as opposed to an individual) involved and it's usually a lot more.

If it's a sealant rather than an adhesive, it may not be intended to provide a mechanical joint.

Have you seen the threads below? One thing that I'm less than happy about with going through the under-slab insulation is the transition from the ASHP feed and return into the ducts under the slab. We used Hep2O barrier pipe in a duct through the slab as described in a couple of the threads below, which meant a right angle HEP2O connection was needed just outside the vertical plane of the wall. Nothing wrong with that, but the elbow is very low relative to the surrounding ground, which made it a little awkward the insulate. Ideally you need to think about how you're going to insulate and protect this area longer term given its position. Other than that, this arrangement works well.

Even with a sealant, you have to be religious about wiping up spills to avoid staining. We have a large permanent mark in our kitchen where my wife took a rubbish bag out of the bin, put it on the floor, then went off and did something else. It wasn't picked up again until the next morning, and by then whatever had leaked out of the bag was well and truly soaked into the concrete. Oh, and stuff tends to break when you drop it onto concrete, but that's an issue with tile as well. It very fast to clean though - a large microfibre broom lets you cover a lot of space quickly. It's also heavenly in the middle of a heatwave when you walk in from a stinky hot day and the concrete sucks the heat out of your feet when you take your shoes off (the kids sometimes lie down on it when they come in). Underfloor cooling helps, and again, you'd get the same effects with tile.