Comments by "Peter" (@peter65zzfdfh) on "Technology Connections" channel.

  1. There's generally (but not universally) cheap energy in the USA so they got used to this way of living, now costs are rising some places and nothing was designed just to heat one room (eg by using mini splits).
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  2. Yeah, that was my though for Alex's situation. Here it would work less well, because we have no danger of freezing pipes, people generally turn off their heating when they go out, and thus it has a bigger range to catch up when they get home. (Though I can just turn mine on remotely) and also the difference between inside and outside is barely more than half that of what Alex has.
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  3. Well the heat pump has a bout a 3/4 less impact to my wallet to run so, there's that.
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  4. I run my heat pump 24x7 and I never hear it, because it's not working hard and they ramp down fan speed, power usage and ramp up efficiency when running at lower power settings. Alec is talking about running his furnace 24x7 only on the coldest day of the year. Also, things clicking on and off, are way way more noticeable than a constant extremely quiet sound.
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  5. Alec : I don't know why other countries have switches on their outlets, you can just unplug the device. Also Alec: We risk our lives every time we unplug or plug something in! Brits, Aussies and Kiwi's: you can remove your plugs from the outlet without using a crowbar?
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  6. 3 times too big for the COLDEST POSSIBLE day. Meaning the heat pump would only need to run flat out all the time on the coldest possible day, every other day, it would not. And modern heat pumps are designed to throttle down to lower rates as they are more efficient at lower settings, a bigger unit has a higher minimum setting. Also heat pumps tend to be rated for a number of cycles, the more continuously it's run at a lower setting the longer it will last vs short bursts at a higher setting. The compressor turning on and off is the most wear you can put on a heat pump, having it run at a lower speed for longer is much much much less wear and will prolong the life.
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  7. There's not really such a thing as 'exceeding grid capacity' on a national level. There has ALWAYS been times and locations where a specific area may end up exceeding its local capacity, usually at a peak time (when everyone is getting home from work/school usually), and there's been a lot of excessive building to avoid that. EVs are actually somewhat of an answer to the problem, as there's no reason they need to be charged at that peak time, there's no reason they need to have any negative impact to the grid at that time. If managed right they can actually reduce strain on the grid by charging from those intermittent renewables or when base load has surplus overnight, and have it available for use during peak events. Heat pumps use much much less power than resistive electric heaters, so the overall impact of them is likely a reduction in electricity usage for heating, even if some people are switching from gas. Peak heating demand just isn't at the same time as peak electricity demand. That's more often peak cooling demand (eg, people get home from work in the middle of summer and the house is all hot). So air conditioners are the biggest culprit for grid capacity demands, not so much during the day when solar is probably around, but on very overcast hot days or just after sunset. Most of trying to address capacity is really just dealing with an hour or two of that 'peak' demand, something that tends to rely on batteries / hydro etc to get through. If you snapped your fingers tomorrow and literally EVERYONE had an EV, then maybe they could be a problem. But in reality they are still a small % of the vehicle fleet and that's not likely to change dramatically for the better part of a decade unless you're in Norway.
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  8. It's not relevant since the heating is running all the time to keep pipes from freezing. Yes, it would take longer if the house started at freezing vs an oversized unit, but that's clearly not a real world test for Alec. Heat pumps make heat the same as gas, it won't take any longer for a heatpump of a certain rating to heat up a home vs gas of the same rating. An oversized unit of either will heat it up faster. One of the plusses of smart thermostats is that they can automatically do things like warm up the home before you wake up, so the temperature is right when you wake up, in that case it doesn't matter it takes longer, it's more comfortable vs a manual thermostat you have to jump out of bed in the cold to set and then have it rush to the right temperature fast.
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  9. au contraire, the oversized unit can reduce comfort, efficiency and flexibility when it comes to heat pumps. And increase noise / cycling nuisance when it comes to gas. It's not just about money saved, it's actually a better, more comforatable solution.
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  10. They don't flare off any of the gas here, they compress it into LNG and send it overseas, hence it's WAY WAY more expensive than electricity for the same amount of heat. Literally in this country we have had 'reverse cycle air-conditioners' for 20 years. Mine is still going strong, 20 years in. Quiet, inaudible, nothing like a noisy gas furnace huffing and puffing everywhere. And each room can set its own temperature, and there's no air ducts at all between rooms tor transfer noise. AC/s throttle back as they have inverters, and they operate more efficiently at lower speeds, there's no corrosion, even here a short walk from the beach.
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  11. Heat pumps are 300-700% efficient typically, burning gas for heat is ~90% efficient. Burning gas for electricity is around 53% efficient (at a large scale, less at a small scale). Even with transmission losses a heat pump would only need to be 200% efficient to beat burning gas locally, and they still tend to beat 200% efficient at 4ºF / -15ºC . And all the rest of the time when it's warmer outside they do better. And you don't need to burn gas to power the heat pump, you could have solar, or be using very cheap wind power (provided it's not freezing in Texas where they refused to connect to the national grid because that would lower profits by requiring them to follow rules that require them to winterize turbines ,... ooops.).
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  12. In my country in the warmer areas they are 'reverse cycle air-conditioners' to distinguish them from the earlier air-conditioners (not sold for ~20 years) that only did cooling. And in the cold state or two they are 'heat pumps' because they're almost never used to cool. I was used to RCAC (reverse cycle air conditioner) but I think heat pump is a better name now.
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  13. The furnace label he showed was 92% efficient, and a heat pump is average about 400% efficient. Even burning the gas for electricity it will use less gas for the same heat output if it goes via a heat pump. Switching here caused my heating bill to drop by 3/4..... Can't see a reason why a normal person would need gas, maybe someone under six feet of snow, but in that case a ground source heat pump would be ideal. I haven't had a power outage in 15 years, nor would it be fatal to get one, but if you were that worried about it a backup generator would be fine.
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  14. You're right except when you're talking about an event that is one day every couple of years, there may not be a need to size for that as running an hour of resistive heat for that eventuality isn't going to anywhere near negate the heat pump gains in efficiency, and probably isn't going to come anywhere near the gains from a lower minimum power most of the rest of the time. Even variable speed compressors have a higher minimum the larger they are, and if you end up oversizing the cooling it will actually cut out completely even with a variable compressor and it won't dehumidify nearly enough.
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  15. For gas, sure, But actually it will likely be noisier when running, and more noticeable when it kicks in and out. With heat pumps they can also actually be less efficient if you oversize them (it does depend somewhat on the specifics of the unit, as sometimes there are breaks in models that you can cross that change that). As in, it could be $2 for 10 minutes of heat or $0.90c for 2 times 10 minutes, a much much quieter 2 times 10 minutes as well (I literally cannot hear my heat pump, I have to check the thermostat to see if it's on). Here gas is 5-6x the cost of electric heat pumps, and rising. Electric heat pumps are ~1/4 the running cost of standard resistive electric. You would not want to undersize to the point you were running resistive heat more than on the coldest day of the year, and then only the coldest hour or two.
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  16. Here in warmer states they are 'reverse cycle air conditioners' and in the colder states 'heat pumps' but exactly the same equipment. I don't think anyone's sold a cooling only mode for 20 years. Maybe a portable one or the absolutely cheapest mini split they never actually move any units of. The whole country pretty much needs heating and almost all of it cooling, and outside half a dozen cities there's no piped gas.
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  17. The velocity of the air out of the gas furnace is higher, thus it needs to be hotter to not feel cold. The air out of my heat pump barely moves, it's a light puff, and because it throttles down rather than turns on/off, that light puff of warm air is way way more than enough to keep the place hot, inaudibly, vs a noisy roaring fire beast of a furnace that's clicking loudly on and off and cycling between too hot and too cold. Basically slow warm air all the time > noisy fast hot air for a brief period. I have mine set to 22ºC (71.6F.) It's inaudible, you can't tell it's running at all unless you put your hand up next to it, and the place is that constant temperature all day long. I have 'cold' elderly relatives that make me work up a sweat just sitting when I visit them, and you still can't hear or feel their heat pump working. You can get pretty hot air out of a heat pump, they just run more efficiently at lower temperature differences, thus the short cycling of an oversized unit with too high a minimum operating range will be a) noisier and b) less efficient. Thus it's even more important not to oversize a heat pump.
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  18. With smart thermostats you can have it so that it reaches the warm temperature in time for you to wake up. As an added bonus it's a gentle wake up as it gets warmer. For modern inverter heat pumps this is a plus because they're more efficient the less of a hurry they're in. Yes, if you had to manually set it then you might want to blast the heat so it warms up the whole house in 60 seconds :o
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  19. Lots of places have a supply charge for gas that can mean you're paying a huge amount for something you only need in the (very unlikely) event the other system fails, it's also taking up a lot of space. With a smart thermostat you could start the temperature rise earlier. It's literally 3x+ oversized for the coldest day of the year, on every other day it's even more absurdly oversized. That's possibly less relevant with gas, but with a heat pump, smaller systems have lower minimum power settings and thus can usually run more efficiently (and then in summer dehumidify more etc). So oversizing for the one day a year to be more responsive vs just starting it heating earlier would come at the cost of less efficiency most other days.
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  20. My bills are 1/4 as much with a heat pump vs gas, and just the daily supply charge for gas is more than I usually pay for heat, so I've disconnected the gas entirely. I can't hear the unit when it's running at all, they sell some bad ones, and some quiet ones. No one here installs gas anymore, we've been using heat pumps for 2 decades now. So much cheaper and more flexible to use the one unit for both heating and cooling, vs an inflexible gas unit that only heats. We can have every room its own temperature, no ducts at all, so much better, no need for return air to a central location etc.
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  21. It's unlikely to make much difference in a townhome (vs apartment). For one there's no one above/below, and heat rises. For two heat transfer goes much more through windows than walls (especially well insulated party/fire rated walls). And for three, the difference in temperature between inside and outside was so dramatic that any difference between 73 and even 65 is basically a rounding error. If it was a very old poorly insulated building and the outside temperature was 63 instead of 4, that would make more of a difference. But in that case you'd probably not need the furnace at all.
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  22. Costs much much less here. Like 1/4 as much for a heat pump to produce the same heat vs Gas (gas used to be cheap here, then they built infrastructure to export it, so now we're paying the world market prices instead of it being available in excess). And because of that there's minimal gas heating, and so heat pumps are replacing resistive heaters which use 4x the power. Plus we often have huge amounts of excess power here overnight and in the middle of the day. To the point that some companies offer 'free' power from 11am to 2pm because there's so much solar available.
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  23. The average temperature has become warmer, but the coldest and warmest days aren't that much different. There's just a lot less of the cold days. And a lot more of the warmer days. For things to stay frozen they don't need colder minimums, they need less warm days. The bigger danger is multiple days where it's hot and the temperature doesn't drop overnight, people in many older houses without cooling can end up dying because they never get a chance to cool down overnight. It doesn't end up being the peak's that are the problem, it's the average, you see the average getting hotter in the ocean temperature, which takes many many years to warm up even slightly.
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  24. Yes, heating is a lot, but also keep in mind this is 6kw maximum on the coldest day of the year, to keep the house a (relatively) warm temperature. I know how you feel, having lived in a place with similar weather, when heating isn't required to keep pipes freezing we have poorly built houses and we just rug up and suffer. I moved to a colder climate (not -15 cold!) and now I am much warmer, but my bills are higher, but not that high as the house is fairly warm by itself.
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  25. The 18-24hours is on the coldest days possible. The rest of the time it will be shorter. Lifetimes are often rated in cycles, so turning it on and off more frequently because it's oversized will almost always kill it faster.
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  26. A 60,000 BTU gas furnace running 6 hours is going to produce 360,000 BTU of heat, at a cost of 180,000 BTU of energy. A 20,000 BTU heat pump running 24 hours is going to produce 480,000 BTU of heat at an input cost of energy equivalent to 80,000 to 160,000 BTU worth of input energy (depending on a number of factors including outside temperature and requested inside temperature). Heat pumps have inverters, and the smaller the change the pump is trying to make, the less energy it uses, one heat pump running 50% of the time doing the same work as another running 100% of the time will probably use about 25% more energy to do it. Bigger heat pumps can scale down their usage, so oversizing isn't the end of the world, but they have certain minimums, which will be larger for the larger unit, so while the larger unit may even be more efficient on the coldest day, on average it will be less efficient.
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  27. No, it's only running constantly at full blast on the coldest day of the year, every other day, it's not running constantly at full blast. Modern heat pumps throttle down when not required to run at maximum because they're more efficient running at a consistent lower setting than full blast on / off / full blast. And smaller units tend to have a lower minimum power, so they will generally be more efficient and cycle less often, meaning less wear. As well you'll get a more consistent temperature, since you're not overheating then letting things cool, then overheating etc, it just needs to add a small amount of heat most days to keep the temperature where you set it.
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  28. Combustion isn't complete, actual propane isn't pure (and more and more studies are showing how impure and how bad for you it is) and you will still suffocate if you don't have ventilation, it's consuming the oxygen in that room to make that CO2 and because the combustion isn't complete, it will also produce CO as well as CO2. More and more the less oxygen there is in the room.
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  29. Here we just use individual splits or multi splits. Quiet, efficient, each room can set its own temperature, no air return required, no losses to any ducts (because there aren't any). No air leakage from ducts (again there aren't any).
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  30. Hence the calculator which would size it correctly for those people, it's not one size fits all. If the neighbors weren't in Florida for the polar vortex already they're probably not going. Since heat loss occurs mostly where the temperature difference is higher (and WAY WAY more through windows than walls, much less fire rated walls) there's probably minimal heat coming from neighbors, but also not much loss, whether they are at 50 or 70, compared to when it's 4 outside and you have windows to deal with.
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  31. He's running it at 18.3 overnight when sleeping, in a warm bed, and 20.56 when awake. Also, coat and hat? At 17? That's still T-Shirt weather and I'm in Australia.
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  32. You saw the 'very cold weather' they were dealing with right? You know people use heat pumps in Northern Norway without heat strips right? They have dramatically improved over the last few decades, cold weather isn't really a problem anymore. And if you lived somewhere that regularly had deep snow I would just get a ground source heat pump instead of an air source heat pump and then the air temperature outside is irrelevant. Heat Strips seem to be a USA thing.
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  33. If they're not bedrooms then just an air transfer between them may work. You can get multi splits with 6 (or possibly more) heads. Though at a certain point you may be better off with multiple units so that the minimum output you need to run is lower and thus more efficient, provided you have the space outdoors.
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  34. Doesn't work that way for heat pumps, it's the cycling on and off that will lower equipment life, hence oversizing a unit will decrease its lifespan, even though modern units can throttle down to quieter more efficient settings, there is still a minimum that in milder parts of the year you will hit. The compressor cutting in and out is what causes the most strain on it, it will happily run all day at 40% capacity, but really be upset if it was 100% / 0% frequently. I'd be surprised if it works that way for gas furnaces either but it probably makes less difference. I imagine expansion / contraction cycles also have an impact there, but honestly life for a gas appliance is ultimately down to a few consumables and original build quality.
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  35. You'd be surprised how warm 69 feels in a draft less well insulated house vs 80 in an older home. It's just so much more pleasant. 65 though is warm clothing time, but still warmer than you think. Lots of these gas furnace units blast very hot air and one part of the room ends up too hot, one part too cold, and it's hard to find the just right area. Whereas an inverter heat pump can just sit there puffing out small amounts of air only slightly warmer than ambient non stop.
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  36. Keep in mind this was the absolute coldest it gets basically, every other day the 3x oversized system will probably be 6x oversized. And it's running at 100% for several hours on that one day, which isn't dramatic. If that was for weeks then sure it ought be bigger. Also, -15ºC is .... 'Mild' ? Jesus.
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  37. My dishwasher has a spot to put tablets in the cutlery basket, I assume they dissolve a lot slower than if just sitting in water.
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  38. You need to experience a decent, modern, inverter unit. They throttle down and do not need to blow air that fast, also one of the reason for larger ducts is so that the air velocity can actually be lower, so there's less of a breeze than with a gas furnace. Gas furnaces need to be warmer to avoid what you get for free with a larger heat pump vent (or a split system). Also more oversized units (as Alec points out) will have a higher minimum flow rate, thus probably lead to more colder air, vs a right sized unit that doesn't need to push as much are at a minimum, but can fill it with more heat per unit volume at the more efficient setting. Gas here increased in price about 10x over the last 10 years. I saved a heap switching away from it. It's a white elephant here, a massive cost saving to go to heat pumps. Also the irony in you believing if there was a dire threat we'd be moving away while noting the unstoppable impact of companies and governments pushing the responsibility onto you so they don't have to take any? Yeah, that's why we've not made major moves. People whined about 'paid bags' at stores here for all of 2 months before 99% of people brought their own reusable bags they bought once for $1 then used for the next 5 years, and everyone else got on with it. I get it change feels hard, but it's honestly not. Hope you get better from your depression. Things are not as bad as you think, the solutions are easy and convenient, once people swore they'd never use computers, then never use mobile phones, then never use the internet, now those people are swearing off whatever else on that internet they swore they'd never use.
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  39. Some of the older and cheaper ACs (and the occasional modern 'cheap' one) just had to run the fan far too often because they'd cycle on/off. New inverter units can step the fan down to basically inaudible, and if you're in a well insulated house they never need to be running at higher power, or that much above ambient temperature to keep it warm. So you end up with a tiny inaudible puff of warm air keeping everything as hot as you want it.
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  40. Because modern units are designed to ramp down, they don't need to run at 100% all the time, they are very quickly at 25% and operating more efficiently, and much quieter, they use a heap less power than old units that cranked on to 100% then off, and it's much less noticeable than a start/stop, what little noise there is constant. You can get units that are basically inaudible, even ductless units, once you have a ducted system you *absolutely cannot hear them*, the noise floor is below a whisper. Cheap units are bad, good units are good. Never seen a house with heat strips, not for 20 years here. Just simply not required.
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  41. It's a net reduction from things like heat strips which use way more power. Also, the power grid tends to be most stretched when people get home from work, in summer, and need cooling. The peak demand time for heating is during the night when the grid has ample spare capacity as it needs spare to deal with the evening peak.
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  42. Likely the gas has a daily supply charge that will make the few hours a day for a day or two a year the resistive heaters need to run look damn cheap if that's his last gas appliance. Which judging from the induction videos, it probably is. Also probably wants/needs that cupboard space back. And I assume the heat strips are there already? As a backup to the gas?
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  43. It's crazy you guys size heat pumps in tons and use kWh for electricity, here heat pumps are sized in equivalent kWh to their heat output. (not input which is usually ~1/4 as much). Looks like 3.5 tons is 12.3 kilowatt so potentially that recommendation is oversized by more than 6x for heating. But could be different for cooling.
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  44. Should still be 1/2 to 1/3 resistive heat costs. Gas depends on where you are, here gas was cheap, now it very much is not and it would be more still. Though fortunately it gets to 20 F for about an hour a dozen times a year. Biggest plus is if you have a multi split you can just heat the bedroom and then the rest you just need to keep above freezing (if relevant).
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  45. SEER/SEER2 is better than COP, here we only use COP and I'm jealous of places that use SEER because COP isn't static. eg, a unit will not have a fixed COP, it will have a COP for a given set of indoor and outdoor conditions, so a manufacturer will list a COP for heating that shows the unit is very good at heating when it's already warm outside.... SEER takes into account climate to get more of an 'average COP' for your area. But then we use kW as heating/cooling capacity not BTUs/Tons so no jealousy there. Also, we don't have 'defrost cycles' or 'resistive heating' in our RCAC units. I don't think discovering 'a fan' is anything amazing.
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  46. If you note, if it was half the size it still wouldn't even have a 50% duty cycle. On the COLDEST day of the year it was at least 3x the required size, being extremely conservative. Most days will not even be that cold. Most equipment is rated in cycles, short cycling will kill things faster.
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  47. Gas used to be cheap in Australia, not anymore, we built an export terminal so now instead of an excess of gas, it's all being sold on the international market, and heat pumps are way, way cheaper to run. Not to mention juts the daily supply charge for having gas is more than I spend on 2 years of heating with a heat pump even if the gas was literally free.
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  48. 40 cents / KWh? That's crazy. Average rate just in the first place I looked in California seems to average 12.4c KWh. Even the most expensive, summer peak, peak hours of the day time of use charge seems to be 23.1c. You seem to be getting ripped off you should probably flip providers. Here gas would cost me way way more.
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  49. One of the things with more modern draft proofed / double glazed houses is they feel warmer at lower temperatures. I moved into a newer house and lowered my usual daytime set temperature from 76 to 70. There's much less gradient too.
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  50. A couple of years ago I ninja installed one of these in my apartment building (I was the only owner in the whole building). Because the people below me kept slamming the door. Problem solved. I also fitted a smart lock (and gave each occupant a code) because no one had the key to the other one. Combined, the door would shut and automatically lock, no longer slam, could be opened in one direction without having to use the handle etc. It was great. But yes, occasionally people did try and defeat it with a brick.
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  51. If you have a new home with good quality windows / insulation and a well draught sealed home it feels many degrees warmer than an older home that will have a bigger temperature gradient across a room. I imagine if there was one big fan heater instead of them all distributed then it would have felt cold somewhere.
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  52. Yes, they'll run 100% of the time easier than they will turn off and on, it's more on/off cycles of the compressor than duty cycle of the compressor that will lead to wear. They have onboard logic that ramps down the speed they run at when not needed as to be more efficient, this also leads to longer life vs turning the whole thing on and off. Also, this is for the one coldest day of the year, if it was running at 100% flat out, all day for weeks, then it's probably undersized. But a day or two, no problem. I've run mine for weeks and weeks and weeks continuously for over a decade, it just manages its own compressor based on what's the most efficient, they have logic to keep them from doing anything silly like short cycling too hard.
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  53. This isn't actually true with modern AC units, they use less power per unit of heat/cool at lower utilization, as they have inverters and ramp down to lower settings that allow them to more efficiently exchange the heat. They also tend to have a 'minimum' they can run at based on the size of the unit. So a very small unit will 99.9% of the time actually use less power for the same result as a larger unit, assuming the outdoor exchanger is the same size (there are several breaks in indoor sizes where they share the same outdoor unit). Because they ramp down, and are more efficient, the air temperature exiting the ducts doesn't need to be much warmer than the indoor air at all. Yes, if you have a horrifically insulated home, you might feel it needs to be, but any bare minimum modern standard home, you do not want 140 degree air, you will have a boiling hot part of the room and a freezing part of the room when what you want is the whole room being warm. The 'resistive backup' if you watched the video is in case the entire system fails so that pipes don't freeze, not to be used on 99.8% of days. Here we don't get freezing pipes, we wouldn't need any backup. But if you're running a 'resistive backup' for only a couple of hours a year, a smaller system for most of the year will save you money as most of the time it will run in a more efficient zone. Also if you watched the video the ducts are inside, so any heat escaping them is entering the house anyway, more evenly than a furnace blasting it out the vent before shutting off a few seconds later or overheating the whole room.
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  54. Even at -15 for the worst modern heat pump I've seen it's still well over a COP of 2. Though if I was expecting 60 days a year to be that cold I'd probably get a ground source heat pump. The COP for the one coldest day of the year isn't that important, more important are the other days of the year.
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  55. Well you're in luck. Winters have not gotten warmer or cooler minimums. The coldest it gets is basically unchanged pretty much any year this century. There are MORE warm days, but the cold days are not that much warmer, and the warm days are usually not that much warmer. It's just the balance that has shifted. And there's no sign that balance is doing anything but accelerating to the warmer side. If that's the coldest day of the year, and the other resistive heat was there already, it's likely the energy savings from a smaller system every other day will more than offset the cost of running resistive heat for those few hours. If it was weeks and weeks of several hours a day, then you'd have more of a point. Resistive heaters will generally last decades and decades though. I know people with them that have been there for 50 years. They are very dumb, 100% efficient devices. If it was 4F outside I'm not sure I'd hate them as a backup option. If it was regularly 4F outside for weeks and you had six feet of snow I'd get a ground source heat pump instead. Smart thermostats kind of negate the 'time to heat up' problem for Alec. If he's running the heat 24x7 to keep pipes from freezing then it's not coming up from freezing after he's walked in the door, it's always somewhat pleasant and automatically heats up in advance of it being required. Even here where I don't need heat on when I'm out, if it's that cold I can turn on the heat remotely and so walk into a warm house / or set it to wake up to a warm house, which is much better than going into a cold house and having to warm it up quickly.
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  56. You can run a fan for days and days on end without a problem. And this is 300% sized for the coldest day of the year. Most other days it is probably 600% sized or more. Should be fine to run even a heat pump continuously for a day. (It actually won't strictly be running full blast all that time anyway).
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  57. Because of the way heat loss works if he can heat it from 65ºF to 69ºF when it's -15ºC outside, then heating it from 0ºC inside to another lower number is much much easier. Every additional ºC you're trying to heat to can increase power usage by 10%. The COP is much higher when the difference in temperatures between inside and outside is lower, he's shown an absolute worst case and your hypotheticals it wouldn't even break a sweat. Yes, under sizing too much will make it inefficient on that coldest day, but also oversizing it will make it inefficient every other day, as there are minimums larger units usually can't ramp down to, so smaller indoor units tend to have a higher COP (for the same sized outdoor unit especially).
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  58. Alec “I don’t understand switches on sockets” also Alec “Plugging and unplugging causes wear that could burn your house down”.
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  59. Oversizing a modern inverter heat pump will make it die sooner. The biggest wear on a heat pump is when the compressor cycles on and off, with a smaller unit it will run at a lower power for longer, reducing the wear. If you want to make it REALLY die fast, you really oversize it, fortunately at a certain of oversizing it will prevent you from short cycling it too hard and it will just get too hot followed by too cold etc. Yes, you don't want it size so it's running at 100% for weeks, not so much because it will die sooner, but more because it's less efficient at 100% than at lower power settings (and larger units can't go to the lowest power settings a small unit can). But for the coldest single day or two of they year, it'll be fine.
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  60. Gas used to be cheap here, lots of it in the ground. Then someone had the bright idea to build a gas export terminal. Now heating with gas is 3-4x the cost of heating with electricity, (via a heat pump) minimum. :o
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  61. Jeff Bezos founded a company that delivered all over the world, to people with no service, or protectionist policies in their countries that were not ready for competition via post. A thing that was very very hard to do well on a local level, but much easier to do centralized. While AC spec'ing is the opposite.
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