Heat pump SEER rating

[Jane Black]

You are correct with the PC

[Commander Kinsey]

I'd not heard of that. Are they banning the sale of petrol cars by a certain year? There are a handful of electric cars around here but not many. Probably less than 1%. There are electric charging points in a few of the public car parks, but not many. I see the odd charging point in people's driveways, but they're few and far between.

No reason it couldn't.

So common then. Bloody double negatives. I had to cancel those out to see what you meant.

Hang on. 45C to 20C is bigger than say 5C (your colder winters?) to 20C.

Aren't those liable to cause disease? and where do you get the cool water from? Aren't you constantly drawing water form the mains, which is short in Australia?

I think from the specs here (click "specifications"):

're quoting SEER and EER for cooling, and SCOP and COP for heating.

I'm not saying this one's any good, it's just the first one I spotted. I'm not buying one for a few months until I've built the room it's going into, so I haven't done much research.

That is the greenhouse effect. Heat gets through the glass inwards, but fails to leave again.

I thought all you Aussies worried about the ozone depletion bullshit.

Bastard.

Isn't that inconvenient? Unless you spend hours sat doing nothing.

I converted one of mine, and bought another already converted. Both blew the engine. I will never use gas again, unless it was designed to use it by the manufacturer. My current car actually has a GPL light on the dash (which I eventually found out is the backwards way first way of the French writing LPG). So I assume you can buy them with that option fitted.

Whatever, we adapt and do something else.

You could do it to prove a point.

[trader_4]

I assume by single units the poster was referring to window units, not central AC, because he claims that most single units are much less that 13 SEER. You can't buy a central AC that's less than 13 SEER and they go up to 20 and beyond. Window units are rated in EER, and he may be confusing the two ratings.

Not true with two stage AC or heat pumps.

If it's not that hot outside, then the inside temperature, once lowered, isn't going to bounce right back up again in just four minutes. Typically it would run briefly a couple times an hour.

[danny burstein]

[snippp... regarding the brand

Not quite that bad. It'll start off with just a slight bit of cooling, and then ramp up and up over the next couple of minutes.

Haven't measured it exactly...

So yeah, when you come in and first stick your head in the (just turned on...) air flow, you'll only get a hint of refreshment. But 30 seconds, then a minute.. then two.. later it'll be quite a bit more.

- It's got to see if the lower output will be enough. If the room's pretty small, and the walls aren't hot [a], then yeah, 5,000 BTU out of the rated 15,000 will be cooling it down quickly. If the room's bigger, then etc., etc.

[a] one annoying feature in general (and that's The Killer in long term heatwaves like Chicago [b] a decade ago...) is that the building infrastructure (walls, etc.) heats up a _lot_ during the daytime and keeps beking the interior at night.

Same thing, kind of, when coming into an apartment that's been at

95F for a couple of days. The unit can cool the air going through it, but that air quickly gets reheated as it flows along the walls. [b] make that two and a half decades... have you gotten to that point in life where you think something happened last week and it was six months ago, and a memory from last year is really a decade?

[Commander Kinsey]

Why would it do that? Room temp = 90, desired temp = 70, therefore run at full speed surely?

I'm lazy, I set heating/AC to run all the time. I pick a temperature for the house and have it set at that 24/7. People say that wastes money, but not much. Turning the heating or AC off while you're out just means the temperature difference between inside and outside (as in how much heat or cold you lose) is maybe 10C instead of 8C. So I waste 25% at those times. Who cares?

I wouldn't design it like that. I'd make it run slowly if the temperature difference was small, and fast if the temperature difference was large. Clearly if it's small it's just topping up, but if it's large it's because you've just got in and you want a lot at once.

Wouldn't happen if you just left the unit on all the time.

[Commander Kinsey]

It's not a window unit, it's not shaped to fit a window. But it has one inside part and one outside part, so works in the same way.

In the USA perhaps. Other countries like the UK (where I live) don't have regulations on AC efficiency.

No, this one lists SEER and EER.

I assume what Danny was saying is if running it on full blast, then the coils themselves will get very cold and hot, hence make it run less efficiently. Best to run a big engine slowly than a little engine fast - Top Gear (a UK motoring program) ran a test where a Toyota Prius drove as fast as possible round a race track, and a large BMW followed it. The BMW used less fuel!

[Commander Kinsey]

It's pointless to have a rating of "SEER 12" if it doesn't specify where that is. Either SEER has to be the same the world over, or it needs to specify what country on the rating. I could otherwise be comparing two units, one with a SEER measured in America and one in the UK. There is ISEER for India, there should be similar letters to prefix it for each country, or the rating is meaningless (incomparable).

[Commander Kinsey]

What am I supposed to do with the question? I don't know how SEER and EER are calculated for different countries, whether the country they're measured in is specified etc.

[Ralph Mowery]

large BMW followed it. The BMW used less fuel!

Most home units are very simple. The cooling and heating 'coils' are either off or on. Just like most electric stoves. The only way to vary the ammount of heat/cool is to cycle them off and on.

There may be some newer units out that do vary the ammount of heat/cool in the coils, but that cost more and most do not want to buy them.

[Bod F]

Buy the highest SEER model available to you that you can afford?

Or buy the mid-range model?

Or buy the cheapest one if you're a skinflint.

[The Natural Philosopher]

Not correlated.

[The Natural Philosopher]

...has no relevance to this duscussion...

..implies the opposite...

[Commander Kinsey]

I'm worse. I can be too sleepy to continue what I'm doing, but when I go to bed I lie there for up to 2 hours before I can sleep. Alcohol and marijuana helps, but it's still not enough. And sleeping tablets make me pass out instead of sleeping, which makes me feel like shit.

[Commander Kinsey]

Ahhh, I forgot they say cycles for some reason. English but not English.

[Commander Kinsey]

Not sure when that came into effect, but I know someone with a 2kW vacuum cleaner that she bought only about 5 years ago. Why on earth would you limit something that uses about 0.0000001% of the world's electricity? It's as daft as hosepipe bans. It's not often we run low on water in the UK, but when we do, they ban hosepipes, despite domestic water use being only 5%, the rest is commercial. I just use one anyway then say I didn't know about the ban (which I usually don't until someone tells me as I don't read newspapers). Or just fill a watering can with a hosepipe the use that. I pissed off a neighbour once by walking around the garden using a watering can with the hose in it refilling it. She said "you're flouting the law!"

[Commander Kinsey]

It's still a lie, they stated the CAMERA was 10MP, not one part of it. That's like Ford selling you a car that can "go 200mph" - when in actual fact only the wheels can do that, the engine can't.

[Commander Kinsey]

No it isn't, apart from the frequency. All they have is the ability to centre tap it to get 120V. I doubt AC does that.

Not for most houses. To get 3 phase I'd have to pay the electricity company to install two extra cables from the pavement to my house. My two next door neighbours will probably have the other two phases, so it won't be a long cable.

[trader_4]

Well, IDK what exactly you had. But you and Danny were comparing it to a mini-split. A mini-split can and often is just two pieces one inside, one outside. Some will support more than one inside unit. So, what you say isn't a mini-split sounds like one to me, so far.

That's quite shocking, what with global warming and all the other things being regulated and controlled in Europe as a result.

Yes, I agree and have no issue with that. But I've never seen a system where it runs on one minute, then off four. When it's not that hot outside the AC runs long enough to drop the temperature down about a degree. If it's mild outside, the inside temp isn't going back up a degree in just four minutes. Now would anything close to a working, realistic system cool off the place in just a minute, even on a mild day. Running for 5 mins, then being off for 30 mins or an hour is what you see.

[trader_4]

The SEER is a measure of how one unit compares to another in a test setting. I highly doubt that a 10 SEER unit is going to cost less to run than a 15 SEER or 20 SEER, no matter where you install it. The higher SEER units are more advanced, more costly designs. How long the payback for the increased cost is depends on the cost of electric and how much you use it.

[Commander Kinsey]

The word split suggests you get at least two indoor units.

Global warming is bullshit, and we don't use much AC. Eventually we'll use heat pumps for heating, then no doubt they'll introduce tree hugging bullshit. But having left the EU, we might not.

Agreed.