On Tue, 22 Oct 2019 00:44:45 +0100, Rod Speed wrote:



"Commander Kinsey" wrote in message
newsp.z908xwllwdg98l@glass...
On Mon, 21 Oct 2019 23:23:19 +0100, alan_m wrote:

On 21/10/2019 20:50, A noiseless patient Spider wrote:
On 10/21/2019 3:20 PM, Commander Kinsey wrote:
Why can't I find a heat pump with a good SEER rating? The USA has a
law stating 13 minimum. Yet here in the UK, I looked at Panasonic and
they're all 7 to 11!

It's because we use 120/240 volt 60 Hz two-phase. Your single-phase 50
Hz is less efficient.

https://www.energystar.gov/products/...rce_heat_pumps

Doesn't it also depend on if it's been optimised for air conditioning to
cool air in the summer rather than being optimised for heating during
the winter in climates such as the UK?

Is that necessary?

For the best SEER rating, yep.

If it's reversible, isn't it just that?

Nope. The problem with using them for heating
in a climate like yours is that the outside heat
collector does ice up and you need a much
bigger outside heat absorber to get the best
SEER rating for winter heating.

Argh, so I really need to find data for the heating and the cooling cycle.

You don't get that effect with summer aircons.

Obviously it will be less efficient when it's pushing heat through a
larger gradient (which will happen in heating mode), but that can't be
helped.

It can actually with two stage designs.

Two seperate circuits? Two condensers etc?

Consider also it appears from many of the examples I've seen honesty
doesn't seem to be part of USA advertising.

Don't they have a government body to check they're honest?

Nope.

And it ain't just the USA - almost everything you buy with a rating is a
lie.

Not a lie so much as its hard to come up with a single digit number
that really does rank the devices properly, even with something as
simple as a fridge or freezer, let alone a heat pump.

Bull****. A camera makes a certain number of pixels. A battery has a certain number of amp hours. For example, I bought a "Probat" (****ty make) car battery, and an Exide (good make) car battery. They were both rated at 45 Ah. I charged them both fully. Then I connected each to a car headlamp bulb, drawing about 4 amps. I measured the current over time and worked out the real Ah. The Exide was almost spot on, about 43 Ah.. The Probat was 32 Ah. I got a partial refund when I yelled at the seller. Cameras have the same problem. My Fuji camera claims 10MP. But it's very easy to determine it's actually about 2.5MP. Take a picture at full resolution in favourable lighting. Load it into Photoshop and reduce the size to 2.5MP. Save it. Load it again, then enlarge back to 10MP. Clearly this image now only has 2.5MP of data. Compare this image to the original from the camera. They're identical! So the camera was giving out no more data than a 2.5MP file. They lied.

Cameras with less megapixels than they say,

That's not a rating, that's a lie about the specs.

Rating, specs, same thing. It's a number defining the capabilities of the device.

batteries with less capacity than they say, etc.

Ditto. But that doesn't happen with the best of them like
the Panasonic Li ion batterys or the apple iphone batterys

Iphone! BUAHAHAAH!!! Everyone I know with an Iphone is constantly moaning it went flat. My £13 phone lasts for WEEKS between charges. What Apple did wrong was the same mistake Clive Sinclair made - making things smaller to the cost of everything else. No room for enough battery. My phone uses two 18650 Li Ion batteries - same as a cycle lamp - total is 4.2V 6Ah. Easy to get replacements too. Oh and you don't need special tools to open the battery cover. And the phone doesn't deliberately disable itself if an unauthorised person opens it.

Its more complicated with smartphone talk time which
varys quite a bit depending on whether you are in a
strong signal area or a weak one where the phone
need to transmit more power to be seen by the base.

Yes, a phone can't guarantee battery life, but the battery itself can state a very precise Ah. They could also simply quote the measurement along with the conditions required. Eg. this car will get 50mpg if you drive on a motorway at a constant 70mph. Or this phone will allow you to talk for 3 hours if your signal strength is 90%.

Every time I buy something like that, I test it thoroughly, then get a
partial refund :-)

You don't with Panasonic Li ion batterys.

Agreed - they don't lie. I have 6 of those 18650 Panasonics here. 3Ah on the label, 3Ah on my test. Even Samsung only get 80% of their rating.. But try Chinese **** and you get 20%!