Aircon Decisions ?

[torrenova]

After some research, I've come up with this layman's definition of an inverter

The final major thing we learned about modern air-conditioners is what a label reading “Inverter” means. There’s a Wikipedia page Wikipedia inverter explantion explaining the technicalities, but essentially, this means that the compressor (the pump that moves refrigerant between the coils and allows it to transfer heat from inside to out or vice versa) is able to run at variable speeds rather than – as was always the case with older air-conditioners – to only be either running at full speed or off.

This means the system can work a bit more intelligently: it senses the temperature of the room, compares the present air temperature with the desired temperature and adjusts its output accordingly. So when the system is switched on in air-conditioner mode and the room is very warm, the system will put out a lot of very cold air, but as the room cools, the temperature of the cooling coils will be allowed to gradually rise and the fan speed will decrease. When the air is at the desired temperature, the unit will run very slowly, just circulating air and cooling it only enough to offset any heat gain in the room (due to appliances, sun shining through window or whatever). In heating mode, it will similarly produce a lot of heat when it senses the room is cold and then gradually reduce the heat output as the air temperature gets closer to the user’s desired temperature.

Supposedly, Inverter technology can result in a 30% improvement in energy efficiency.

Source: http://www.italymag.co.uk/forums/cost-livi...nditioners.html

So is it worth it ? A rough increase for the same BTU inverter machine is between 50% and 75%. Now is it really worth that much of an increase for economy or are there (for me important) other benefits like noise reduction ?

What about aircons which heat as well ? We have in Japan for donkey's years but I've found one here, a Mitsubishi - what do people think ? (Buriram does get cold in winter).

We need about a 12000 BTU or thereabouts but even 9000 might do. Why pay 40k for a heater one or 25k to 35k for an inverter when you can get a non inverter by the same people for 17k and a cheapo make one for 12k ?

Can someone make a convincing argument for me please ? Thanks

[Naam]

-i can't comment on heating. only you know what comfort level is desired.

-the noise reduction is irrelevant as it concerns only the outside unit. all outside units are rather quiet anyway.

-energy efficiency depends on individual usage. the marketing people and treehuggers highly overrate inverter units in this respect.

bottom line (just my personal opinion): forget about inverter and go for a conventional unit.

[GungaDin]

I'd like to see more replies on this subject too.

I've just rec'd a quote for some no-name aircons as follows;

No inverters or heaters.

9000 btu 15,000B

12000 btu 16,000B

2 x 16,000 btu 34,000B (40m2 room)

Cost includes installation.

I thought the prices a bit high for no-names.

The no-names are Midea Elite & Fujibishi

Any comments?

cheers

[torrenova]

-i can't comment on heating. only you know what comfort level is desired.

-the noise reduction is irrelevant as it concerns only the outside unit. all outside units are rather quiet anyway.

-energy efficiency depends on individual usage. the marketing people and treehuggers highly overrate inverter units in this respect.

bottom line (just my personal opinion): forget about inverter and go for a conventional unit.

Yeah Naam, I don't see the "big" saving on energy efficiency either and if it is just a few percent and the unit costs 50% more then you might have a long wait until you hit positive territory. Like double glazing, you buy it for all reasons other than energy saving.

I've lived in some places where the outside unit was really noisy and some where the inside unit was really noisy. I even had a new Daikin replaced twice because it was too noisy.

In this case, the wall and window quality is poor so noise is an issue. But, for a couple of decibels, I don't think 50%+ extra is worth it. Now if I was buying half a dozen I might put an inverter in the bedroom and others elsewhere and see if it made difference.

The Mitsubishi ones which will heat as well are the Super Inverter models but these are about 150% to 200% of the cheapest models with brand names.

As the room is about 16m2 which minus wardrobes and an internal alcove (?) reduces to a little over 12m2 I could perhaps get away with just chucking in a BTU 9000 model (12 * 750 = 9000) which would cost me around 15k for Daikin or similar though the 12,000 would only be an extra couple of thousand.

For me it is the noise and the lack of need (due to not being there so often) to chuck $1000+ at the problem.