Thinking of getting a new A/C? Here's an interesting paper - Inverter vs Non-Inverter

[david555]

4 minutes ago, Crossy said:

 

But, we are not talking about 10 years ago are we???

 

What was the correct decision then (it likely was) may be not be the correct one now (it probably isn't).

 

If your current units are functioning OK and your bills are not excessive why change anything?

 

That is why i said i can only compare whit my knowledge and price at that time ......

 

not comparing with this new items , and any simple handy village man could repair  that time easy the non inverters .....,now maybe also those new types he can handle ...

 

And not a giant house with multiple AC. rooms 

Just a humble 60 m2 condo ????

????

[sometimewoodworker]

4 hours ago, david555 said:

About Thai electric price i pay 428,35 Thb for 111 units direct from PEA so 3,86 Thbt a unit ,......no middle man / woman  involved jacking up the money for his / her pocket ????

That isn’t cheap electricity. That is low usage of electricity so your bill is low, and that’s rather different. 

[MrJ2U]

I've found that the inverters I've used struggle with the high humidity.

 

I ended up replacing them

 

I've replaced them with regular Mitsubishi's.

 

Mitsubishi's have a dry function that saves electricity.

 

I see the study was in Saudia Arabia where the heat is harsh but they have lower humidity.  A dry heat.

 

Inverters just haven't worked for me.  I like it around 22 Celsius to sleep.

 

 

 

 

[david555]

1 hour ago, sometimewoodworker said:

That isn’t cheap electricity. That is low usage of electricity so your bill is low, and that’s rather different. 

Whatever you say or find ..... i guess you are the always right one ????,

so my bill is low as i don't use 6 AC. i guess ???? might be the inverter fridge who make that low consumption figure ....

[sometimewoodworker]

5 hours ago, david555 said:

Whatever you say or find ..... i guess you are the always right one ????,

so my bill is low as i don't use 6 AC. i guess ???? might be the inverter fridge who make that low consumption figure ....

How ever you like to convince yourself that electricity is cheap in Thailand because your bill is low doesn’t make it true.
 

The average cost of electricity in the USA is a little over $0.12 kWh  or ฿4.33 

in Thailand for a moderate size house it is around ฿ 4.22 or virtually the same cost as in the USA

 

Certainly there are countries that have electricity that is higher priced than Thailand, so your original home country may be higher priced than Thailand.

 

as an example the average consumption per household in Japan and the U.K. is around 242 kWh so your usage is well under half that. Congratulations on being economical in your power consumption, you are very much lower than the average in Thailand which ever region you live in.

 

[Husain Tula]

I certainly verify this statement as I have noticed it personally.  When I had my old split air-conditioning unit, my average monthly bill was about THB 4,000.  This was recorded as an average for a period of 2 years.

 

Once I replaced it with a new "Carrier" that is even bigger in capacity and fitted with inverter, I was shocked to see my monthly bill hardly goes over THB 2,000.  It has been almost a year since I replaced it.

 

Definitely worth it.  By the way, I live in Bangkok, just in case.

[Pooreye]

On 3/18/2022 at 12:50 PM, thaisail said:

I have had my three Samsung double inverter copper coil 12,000 BTU split unit aircons for more than one year now. Because we live in a more temporate location in Thailand, Chiang Khan, we do not run any AC from December to March. For the rest of the year, we start out running the AC in the living room in the afternoon and by sunset, the AC is no longer needed. However in the bedroom, we start using the AC as soon as the night time temperatures are staying above 22. 

 

Before going to bed, I put the remote mode on "fast". This will set the temperature at 16 and the fan and compressor will slowly ramp up to maximum rpms. I leave this setting for maybe 10 minutes until the room is cooled off. I have found that with the new technology Samsung Inverter AC's, that if I set the remotes on "quiet" which will slow down the fan until the minimum RPM and direct the cold air direct to the bed, I can set the night time temperature to 25 and with a thick sheet or light blanket, the AC will keep us at the maximum comfort. The fan is so quiet and the compressor is running at minimum rpms until the night time temperatures reach around minumum of 30 and the compressor will start to speed up slowly but the fan will run at minimum speed all night and the room is going to stay at 25 all night. I set the timer on the remote to stop the AC at 7 am and the room slowly warms up to the ambiant temerature in the rest of the house. 

 

The main reason that the inverter technology is more efficiant has to do with the laws of thermodynanics. If your AC compressor is always running at a very slow speed, the thermostat is keeping the temperature at a steady temperature which will be controlled by the speed that the compressor is turning. With the old style AC units, the compressor will run at maximum until the temperature reaches say 24. Then the compressor will stop until the temperature reaches the cut in temperature of say 26. This will give an average temperature of say 25. The major loss of efficiancy is the energy required to lower the room temperature by 2 degrees about 10 to 20 times per 24 hours. With inverter technology, this does not happen and therefor this energy loss does not occur. 

 

The other big energy is the compressor starting current with is around 6 times the current required to run the compressor. So if the compressor starts 10-20 times per 24 hours, this starting surge will start adding Kws to your meter and your total power consumption will be higher as a result. With double inverter technology the compressor and the fan will both have what is called a soft start. This surge will be far lower because the speed of both will gradually increase and this will avoid that massive surge that comes with a traditional AC compressor. You will also save money when you build a house because the cross sectional area of your conductors can be less since your amp draw will be lower because of the lack of surges when thing start direct on line.

 

But for me the best reason to go with inverter is the noise. I really like the Samsung system because when I run the AC's in "quiet" mode, there is almost no noise either inside or out. Unfortunately I found out that Daikin was the first company to have the patent on the inverter technology so they have had a 10 year period where they were either the only one selling these units or other companies had to pay a license fee to use this technology. I think this 10 year pattent has now run out and all the companies can now sell inverter technology. So Daikin has has a 10 year head start on this technology and by luck the double inverter 9000 BTU until in our bungalow, where we lived during construction of our new house was really the gold standard. I wish I had known this information about Diakin patent before I ordered the Samsung AC's. Perhaps by now the other companies have developed better technology than Daikin but one thing I like better about the Diakin is that I can adjust the temperature settings by 0.5 degrees increments instead of 1 degree like my Samsung units. This is only a matter of comfort so that if 25 is too hot we can set the room at 24.5 degrees and end the argument with the wife. 

 

The only disadvatage I can see with inverter technology is the extra cost to buy the AC units. But it seems that this cost difference has decreased over the last several years because they are now selling more inverter units than the classic type and the companies have gotten back their research and develpment cost. The other reason is of course repair and maintenance. Because the technology is new, many AC repair technicians are not familiar with them so finding a qualified repair man can be a chalenge in remote areas of Thailand. This problem will eventially go away as inverter technology takes over the market the same as happened already with diesel engines that went to electronic common rail from the classic mechanic deisel engines from the old days. The Thai mechanics had to learn common rail quickly. 

 

But there is one thing that is absolutely critical for using this new inverter technology. You must have a clean power supply. I have installed a high and low voltage safety switch that will trip the entire house power if the voltage goes below 190 volts or higher than 250 volts or If my amps go higher than 40 amps, the entire house will black out and with all of these functions, the power will automatically be restored when the electricity supply returns to normal with a built in timer. I fitted MOVs on my power inlet to deal with lightning surges. The cost the adjustable voltage protector with digital display and timer for the entire house is only 400 baht and the MOV's was less than 135 baht, both with Lazada. Without these feature you may be having to replace your inverter AC units or at least having very costly repairs. 

 

The second very important thing to do when changing from classic to inverter technology is make sure that the earth connection is using the same size condutor as the phase and the neutral. This is really critical the safe and efficient function of inverter technology. Make sure that your earthing rod is 2.5 meters in the ground and goes into wet earth so that there is a very good earth connection and of course, earth fault protection with no more than 30 mA trip setting. I have had a nightmare getting my electrical contractor to conform to these specification and I had to watch him like a hawk to get this done. In fact, he tried to cheat me by not even having an earthwire from the three new Samsung AC units. I had in the end have to have him put conduite around the outside of the house with separate earth wires of the correct cross sectional area going to the earth rod direct which cost me a lot of extra money but it had to be done. 

 

Anyway I just wasted the entire morning writing this essay when I should have be out intalling the new faucets that need to be installed but writing this was better then going outside to work in the hot sun! My wife does not agree!

A very good read. That explains the stopping of our big inverter fridge, we sometimes found it quiet and not working. Must to unplug it, wait a few minutes, press the reset button inside, replug it and then it will start again.

It took a few months until I realized it was because I sometimes use my small stick welder…

 

Now the interresting thing: We are quite new to the house, and first months I just used an existing socket outlet at back of house. No fridge problems despite welding a fewtimes per week.

 

Later I found out the feeding cable was only 1 sq.mm, and about 15 m long snaking around from various sockets inside house. So I changed the outside socket to get fed from another circuit of 1,5 sq.mm cable instead, unfortunately the fridge circuit. Now the fridge stopping probems arised.

 

Well after a few weeks I realised why, and bought 20 m 2,5 sqmm cable, and rerouted it directly all the way to the fusebox upstairs. Put it on a the separate ac fuse. 
 

But to my surprise, the fridge still stops although not as easy. But it still cut out sometimes. At this step is where I am of today. Next step, I think check more carefully inside fusebox for wire thicknesses and routing.

Or go back to weld via long 1 sqmm wire.

Or try to remember to unplug/replug the fridge every time.

House voltage about 210-220 volts every time I check.

Maybe get an analog meter and let wife check when I weld.

Maybe someone have suggestions?

 

 

 

[sometimewoodworker]

7 minutes ago, Pooreye said:

A very good read. That explains the stopping of our big inverter fridge, we sometimes found it quiet and not working. Must to unplug it, wait a few minutes, press the reset button inside, replug it and then it will start again.

It took a few months until I realized it was because I sometimes use my small stick welder…

 

Now the interresting thing: We are quite new to the house, and first months I just used an existing socket outlet at back of house. No fridge problems despite welding a fewtimes per week.

 

Later I found out the feeding cable was only 1 sq.mm, and about 15 m long snaking around from various sockets inside house. So I changed the outside socket to get fed from another circuit of 1,5 sq.mm cable instead, unfortunately the fridge circuit. Now the fridge stopping probems arised.

 

Well after a few weeks I realised why, and bought 20 m 2,5 sqm cable, and rerouted it directly all the way to the fusebox upstairs. Put it on a the separate ac fuse. 
 

But to my surprise, the fridge still stops although not as easy. But it still cut out sometimes. At this step is where I am of today. Next step, I think check more carefully inside fusebox for wire thicknesses and routing.

Or go back to weld via long 1 sqm wire.

Or try to remember to unplug/replug the fridge every time.

House voltage about 210-220 volts every time I check.

Maybe get an analog meter and let wife check when I weld.

Maybe someone have suggestions?

 

 

 

Your fridge is quite possibly shutting off due to low voltage.

 

a welder is a power hungry beast, it is certainly likely that it is pulling your supply voltage so low that the fridge shuts down. If we have 2 showers running our supply is pulled down by about 25~30 volts. So you need to monitor what’s happening to your house voltage when you weld.

 

Too small a supply cable to the welder is a poor idea as you may overheat it enough for a fire.

[bankruatsteve]

I have a large Samsung inverter refrigerator that is not easy for me to hear if it is running or not.  It is most obvious when it goes into defrost mode (at least I think that is why) and I can easily hear it running.  Otherwise, I have to put my ear on the skin in attempt to determine.  So, just saying that your unit might be like that.  The only way to know for sure if it is not running is if you see a temperature drop.

[sometimewoodworker]

2 hours ago, bankruatsteve said:

I have a large Samsung inverter refrigerator that is not easy for me to hear if it is running or not.  It is most obvious when it goes into defrost mode (at least I think that is why) and I can easily hear it running.  Otherwise, I have to put my ear on the skin in attempt to determine.  So, just saying that your unit might be like that.  The only way to know for sure if it is not running is if you see a temperature drop.

 @bankruatsteve You have your attribution wrong in the above quote. It was posted by @Pooreye not @sometimewoodworker

[Crossy]

3 minutes ago, sometimewoodworker said:

 @bankruatsteve You have your attribution wrong in the above quote. It was posted by @Pooreye not @sometimewoodworker

 

I don't seem to be able to edit the attribution, so I've simply removed it to prevent confusion.

 

[bankruatsteve]

39 minutes ago, sometimewoodworker said:

You have your attribution wrong

Since I didn't attribute to anyone, it could not be wrong.

[sometimewoodworker]

41 minutes ago, Crossy said:

 

I don't seem to be able to edit the attribution, so I've simply removed it to prevent confusion.

 

I’ve found that if I edit the quote 

 

41 minutes ago, Crossy said:

“don't seem to be able to edit the attribution, so I've simply removed it to prevent confusion.”.  

Quote

I can fool the editor software, by deleting just the wrong position. So it looks as if I can put interesting words into other’s mouths 

I am the almighty omnipresent omnipotent modest editorial god @Crossy writing this, ????  Or am I? 55555

[sometimewoodworker]

1 minute ago, bankruatsteve said:

Since I didn't attribute to anyone, it could not be wrong.

You did just like this is attributed to you. But @Crossy fixed it by removing the attributed quote

[bankruatsteve]

Oh.  i must have quoted from your quote of his then.  Oops.

[NoshowJones]

22 hours ago, Tropicalevo said:

Same for me and I pay 9 baht per unit for electricity. A big saving.

And the inverter unit is much quieter.

No science behind my comment. Just an observation.

9 Bt per unit?? That is about double the government rate.

Someone is conning you. Probably your landlord.

[BE88]

I confirm the consumption is much lower for my recent air conditioner, that is due to the fact that the engine is made with new materials more efficient in electricity such as various rare earths.

[sometimewoodworker]

16 minutes ago, bankruatsteve said:

Oh.  i must have quoted from your quote of his then.  Oops.

No problem, if you select slightly incorrectly or delete at the wrong point in editing it can happen.

 

just expand my second quote of @Crossy above (if he doesn’t edit it before you get there ) you can see his opinion of himself, maybe?

 

the new SW has the odd interesting bug ???? in it 

[nrasmussen]

9 hours ago, sometimewoodworker said:

How ever you like to convince yourself that electricity is cheap in Thailand because your bill is low doesn’t make it true.
 

The average cost of electricity in the USA is a little over $0.12 kWh  or ฿4.33 

in Thailand for a moderate size house it is around ฿ 4.22 or virtually the same cost as in the USA

 

Certainly there are countries that have electricity that is higher priced than Thailand, so your original home country may be higher priced than Thailand.

 

as an example the average consumption per household in Japan and the U.K. is around 242 kWh so your usage is well under half that. Congratulations on being economical in your power consumption, you are very much lower than the average in Thailand which ever region you live in.

 

The price per kWh I pay in Thailand is about half the price I paid in my home country (Denmark), so I call it very cheap here.

[spidermike007]

Inverters are a big improvement. Mine are quieter, and alot more efficient. Though they cost more, my annual electric savings is significant. Perhaps as much as 10,000 baht a year. 

 

Some are not comfortable embracing new and improved technology. Some of us love it! 

[thaisail]

12 hours ago, Pooreye said:

A very good read. That explains the stopping of our big inverter fridge, we sometimes found it quiet and not working. Must to unplug it, wait a few minutes, press the reset button inside, replug it and then it will start again.

It took a few months until I realized it was because I sometimes use my small stick welder…

 

Now the interresting thing: We are quite new to the house, and first months I just used an existing socket outlet at back of house. No fridge problems despite welding a fewtimes per week.

 

Later I found out the feeding cable was only 1 sq.mm, and about 15 m long snaking around from various sockets inside house. So I changed the outside socket to get fed from another circuit of 1,5 sq.mm cable instead, unfortunately the fridge circuit. Now the fridge stopping probems arised.

 

Well after a few weeks I realised why, and bought 20 m 2,5 sqmm cable, and rerouted it directly all the way to the fusebox upstairs. Put it on a the separate ac fuse. 
 

But to my surprise, the fridge still stops although not as easy. But it still cut out sometimes. At this step is where I am of today. Next step, I think check more carefully inside fusebox for wire thicknesses and routing.

Or go back to weld via long 1 sqmm wire.

Or try to remember to unplug/replug the fridge every time.

House voltage about 210-220 volts every time I check.

Maybe get an analog meter and let wife check when I weld.

Maybe someone have suggestions?

 

 

 

I have a 10 year old inverter fridge and sometimes the compressor stops when the thermostat gives the command. The fridge compresser can only run so slow. So if the fridge is stopped and does not restart there is a problem with the thermostat maybe. But if the compressor stops and then restarts that is normal in our case. I think that the newer designed inverters will be able to turn much slower and will keep the temperature constant without having to stop. 

[NanLaew]

On 3/18/2022 at 12:50 PM, thaisail said:

But there is one thing that is absolutely critical for using this new inverter technology. You must have a clean power supply.

Since the PEA finally sorted out our moobahn's longstanding low voltage in the evenings, I will now be investing in inverter tech.