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joth last won the day on June 11
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Completed UK's third "Enerphit plus" retrofit, during the pandemic
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Hertfordshire
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Carefully planted and maintained trees can block summer sun but still let in some winter light. That tech is beyond me though (and takes time). You could add brise soleil to the plans, gives you the approval to install them if you ever want to in the future Else +1 for external shutter blinds, it's what the rest of Europe uses surely only time before we wake up to using them more here.
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Self installed Air Conditioner
joth replied to Annker's topic in Mechanical Ventilation with Heat Recovery (MVHR)
I got one of these https://www.appliancesdirect.co.uk/p/eiq-12wminv/electriq-eiq12wminv-wall-split-air-conditioner electriQ Easy-Fit 12000 As other say R290 so no FGAS engineer needed. (But clearly, needed someone more competent than myself 😂) It's in the garden room / gym so currently doing nothing as it's too hot to consider an indoor workout. But I might go sit in there later with a cold drink and set it on 100% -
Self installed Air Conditioner
joth replied to Annker's topic in Mechanical Ventilation with Heat Recovery (MVHR)
There's two types of self-install, the all in one with a large external duct (effectively the same as the "stick a pipe out an open window" portable AC unit), and the pre-charged minisplit with a length of refrigerant pipework you hook up between the indoor and outdoor unit. I went for the latter, but even though I used the soapy water leak test, I did a poor job tightening down the the compression fitting so the refrigerant leaked and I needed to get it professionally recharged. I couldn't find a local AC engineer that would touch R290 so I had to go via the distributor (appliances direct) and pay an arm and a leg for it. It would have been cheaper to have it professionally installed in first place I expect, but hey, learning opportunity! The monoblock hole in wall solution is much more idiot proof, but puts all the noisy gubbins indoors and obv needs a much larger hole core drilled. Whichever you choose the electrics is simple, plug into a 13A socket. The minisplit you do need to connect a flex from indoor to outdoor unit, but it's like two screw terminals - no harder than wiring a plug. -
A2A + A2W ASHP or a more powerful A2W ASHP?
joth replied to puntloos's topic in Air Source Heat Pumps (ASHP)
We had ufh downstairs only. If we needed heat upstairs the fcu could do it, but it's never been necessary (quite the opposite even in winter the master bedroom overheats. The guest room does dip to 18C when unused but warms up as soon as a body is sleeping in it) We're passivhaus retrofit and no issues with the grant. You need to tell your installer that room by room satisfaction is the mcs recommended method but it's not a requirement of BUS so long as whole building heat demand is met, using the passive house phpp Vs group floor emitter power would also satisfy this. -
A2A + A2W ASHP or a more powerful A2W ASHP?
joth replied to puntloos's topic in Air Source Heat Pumps (ASHP)
@puntloos went for option A I helped out with the Loxone programming for it, and I went for option B in my own install a few years before, so I can speak fairly well to the pros and cons. In my experience: Benefits of option A (separate a2a and a2w) - redundancy: still have heating (and cooling) even if one ASHP is out of action. - greater maximum output (if house gets way off target you can run both systems together to get back). (also can heat/cool while doing DHW cycle) - cooling is more effective. A split system using refrigerant can make 5deg C air, vs about 14degC with A2W (due to condensation). (of course, not everyone likes/wants such cold air blowing at them) - relatively easy to phone up an ASHP and an Aircon supplier to have the fix it Benefits of option B (a2w does everything): - lower capital cost (and potentially lower labour cost, esp if you're doing the FCUs yourself) and lower maintenance - slightly easier controls, possibly. In the sense only one setpoint per needed to control both systems, and no chance of heating and cooling fighting each other. - somewhat lower risk of creating uncomfortably low humidity house (as keeping cooling above dew point) - less room needed for outdoor units. (also slightly less planning permission hurdles, although these were recently relaxed somewhat) However finding a supplier to install option B satisfactorily (with FCUs) may be the deal breaker. -
Fancoil - Best invention ever no contest!
joth replied to Dave Jones's topic in Air Source Heat Pumps (ASHP)
One thing to note is sizing depends on the air source going into the FCU. My 2 FCUs are in the loft, so pulling fairly warm air in summer (and cold in winter, if I ever used them for heating. I don't). So my FCU have higher realized output power than if the air coming into it was already "pretty cold". (Output power is determined by the delta between air inlet temp and the water temp, and air flow rate). If you have the FCU in the room being cooled, and down at floor height (where air is naturally cooler anyway) it will not have as much effective output than if you are drawing in hotter air from higher up. Hence why split aircon units are normally installed up high. (but rads installed down low) -
Fancoil - Best invention ever no contest!
joth replied to Dave Jones's topic in Air Source Heat Pumps (ASHP)
Yes I originally ran my FCU at those sorts of temps, while all the pipework is well insulated the snag is all the valves, pumps, mag filter, flow sensor etc etc. There's a lot of extra "gubbins" inline in an ASHP install (at least, there is in mine) and it's really onerous so lag all those components, not to mention makes maintenance of them harder. And even when I tried I found condensation was forming due to tiny gaps and then e.g. the pump gate vales starting to corrode over. So on balance I now just run mine at dew point. (some stuff still gets a little glistening with beads of sweat but no river of condensate running everywhere) This point was easily avoided in my installs: ecodan has two zones with independent setpoints, using an electronic mixing valve, so with the loxone load/weather curve the UFH generally ticks over at 18C flow temp while the FCU at around 12C (due to GF not needing as much cooling as upstairs) -
My answer is very similar to @Dan F I'd already decided on Loxone, was originally desiging the lighting myself but my electrician thought I wasn't putting enough fittings in (from the usual one spot per 1.5m2 grid of approach lights school of thought) so I got a designer to review and then improve the design. The main benefit there is she modelled the lighting to determine if it was sufficient, the alternative would be over provision and dim. Also having loxone I wanted layers of lighting in main spaces, either for reflected atmospheric lighting or direct working lighting, and the designer helped a lot in details to make that work well - e.g. placement for fittings to give and optimal shaped "scallop" of light projected on walls, and suggesting details like small markers inside window reveals. She also had discounts on a few manufacture products she passed through, which against MRP probably paid the fees on its own. I'm really happy we went professional designer route, but it isn't for everybody
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What next for heat pumps after BUS and MCS?
joth replied to joth's topic in Environmental Building Politics
That's fine: No Mains Gas supply => Get cheaper rate mains electricity. What they do with the electricity is up to the home owner. They may choose to go all electric heating (heat pump or resistive), electric cooking, electric car. Or they may keep with non-grid combustion for those things which already is more expensive and likely to get more expensive still over time. -
Yeah, I've given up harping on about this but if you search this forum for "polyphase" you'll see I've been trying to raise awareness of this for a number of years.. 😂
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What next for heat pumps after BUS and MCS?
joth replied to joth's topic in Environmental Building Politics
Looks like the ministers heard me! Sort of. https://www.ft.com/content/b0a9eb3e-38f8-4fc4-8a60-72a12142244f UK ministers consider electricity bill discounts for heat pump owners Households replacing gas boilers may not have to pay green levies on power costs I think it would be crazy to key the discount on presence of a heat pump and/or absence of a gas boiler, which needs surveying and monitoring, rather than simply "does this property have an active gas supply", which can be done with a simple grep on a central database. But hey, ministers must create 2 new bureaucratic hurdles for each one they remove -
If you have a 3 phase supply anyway, and the price is not prohibitively higher, then yes it is. Splitting your generation over phases means less voltage lift per phase, so less risk of the inverter shutting off if the local supply voltage runs high. I believe this depends a lot on DNO and location. I heard a while back Western power were starting to insist on doing 3 phase install (even if only 1 phase brought out of the head) wherever they have capability for it.
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Haven't seen this answered, but, even if you do have different phases to different areas, so long as the whole lot are being supplied via a DNO cut out and single mater, you can still put a 3 phase inverter onto the main 3 phase supply and then divide the phases out to sub distro boards as needed. To a degree this is always going to be the case - there's no such thing as a 3 phase domestic "ring main" socket so some areas of the house will be on different phases. And you'll probably want all 3 phases in the garage anyway for the car lift or, whatever. If you're worried about balancing PV generation to demand across phases, don't. Modern meters to net billing so you're only charged for your net import (or paid for net export) across phases at any given moment in time. Couple more things to note: - you can't buy a 3 phase inverter now "just in case" and upgrade to 3 phase supply later. A 3 phase inverter needs 3 phases to output onto. - A single battery often has a power limit lower than it's capacity, e.g. a 16kWh sized battery may only be able to supply 5kW at any given moment. This also limits it's usefulness for high demand users - do you have DNO approval for 14kW PV ? They may look more kindly to this if on 3 phase. - have you asked for an indicative price for 3 phase? This maybe prohibitive and will answer your question - "The 16kw was advised as part of a recent quote I had." - this is obviously just guess work with so much future expansion of use planned. tldr you can always more than you have, the optimum size depends a lot if you just plan to time shift your PV generation or use it for cheap overnight rate time shifting too. With my tariff (Eon Next) it's actually more financially rewarding to sell all PV generation rather than store it, and then fill the battery from grid each night. But that may change when the tariff is updated next year.....
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A pair of relays and a dedicated permanently powered spur/radial https://knowthecode.io/labs/basics-of-data-and-program-circuitry/episode-6/or-gate-relay-logic But honestly if implanting moods I'd use a set of lighting controls designed for the job, but I would say that 😂
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An advert for 1GB in early to mid -90s is very plausible. My first PC in 1995 had a 1GB HDD... that was my second hard drive, just a few years after purchasing that 20 MB drive for my Amiga. A period of insane growth, bit like AI expansion is now.