How Typical Taiwanese Air-Con Works and the Need for Inverter ACs

I’d like to maintain a comfortable ambient temperature in my apt this summer, however, the AC is a bit of a conundrum. Theoretically, a constant 25C temp would be ideal, however, this unit when set to 25C will waiver in roughly 10 minute intervals between 24C up to 26C (actual temp if measured with an independent thermometer from the middle of the room I suspect would show even greater disparity, something like 23.5 to 26.5C). As a result there’s never a prolonged, comfortably maintained ambient temperature. One has to wonder, is the unit defective or is this essentially a normal unit for Taiwan, hence why everyone drives their ACs at freezing temps, which though uncomfortable, perhaps stay at least consistent at the lower temps (and then out come the extra layers of clothes in summer)?

Do others have this inconsistent temp regulation issue at home? Is most of the country dealing with this by over-driving AC and wearing extra clothes? It is an extraordinarily high price to pay…ok, judgmentally this time, for stupidity. Purchase a properly functioning, quality AC unit for double the cost and save enormous amounts of energy (extrapolating this problem island-wide). Surely we can imagine the additional upfront cost is justified when fully recouped in lower energy bills after a period of years, and then continuing to save beyond that without building up energy demands leading to more coal burning plants, pollution, warming the environment, etc… We’re really uncomfortable, that’s certain, but is the island simply so short-sighted?

I’ve mentioned this issue over several months now to the landlord, whom I do like and get on with quite well, in preparation for the summer. She’s now offered to replace the unacceptable unit (which I cannot say is broken or normal - it’s just unacceptable) with one that can maintain a constant, comfortable temp IF I agree to pay for half (10,000nt of a new 20,000nt unit) and sign a new 1 year lease.

I’m tempted to feign ignorance of the island’s problematic AC practices and insist this is not an upgrade but rather a basic necessity for living. I work at home and the majority of my life and work take place in this environment. It’s not a luxury - it’s a basic necessity, along with running water. If the unit cannot maintain constant temp, then bottom line, it’s not fulfilling it’s function properly. Ball in her court.

What you said it’s essentally incorrect.

The A/C units should be at no less than 5ºC below the outside temperature. Not 25ºC, specially if you’re above 30ºC. One of the main problems in Asia is that people put their A/C units at ludicrously low temperatures (yesterday I visited an apartment in which the owner had his A/C at 20ºC), and then after you exit that place, you have a strong thermal shock, which makes a lot of people get colds in summer.

The A/C most of the times act as a dehumidifier, which helps reduce the thermal discomfort. In a climate like Taiwan’s, getting the humidity out of the equation helps a lot, then lowering the room temperature for a couple of degrees should be enough.

Another cause for the really low temperatures on the A/Cs here is because the insulation for most buildings basically sucks. No double glass, single walls with no air chamber… all that is wasted energy when trying to get your house colder. Just by installing double glasses, I’m sure they could save as much as 50% in their A/C energy consumption. Making an air chamber (or even better, doing it but filling it with insulation) between the exterior walls and the rooms inside the apartment would further those savings and make the interior dryer, too.

This nonexistant insulation causes that people get their A/C temperatures lower than they should, so if you’re in the direct path of the A/C air flow, you get too cold, but if you’re not, you feel hot (and you lower the inside temperature further, increasing the energy consumption, making more likely to get ill because of the A/C, and heating Taipei’s streets a little bit more).

Basically you need an inverter unit that allows the control of the compressor motor so that it varies its power to meet your cooling needs instead of running full strength all the time. Problem is nearly all inverter AC I have seen are large, designed for large rooms and aren’t really energy efficient when used in smaller rooms. You actually want to slightly undersize your AC to the space because AC’s get more efficient with longer run time (it gets cooler for a given energy usage as well as being able to remove humidity more effectively) while burning less energy while the AC is running. An oversized AC will either run in short bursts (which doesn’t really increase comfort) or turn the room into an arctic environment because it has to be set to 16 degrees to get any decent run time, burning way too much electricity. The government offered a 2000nt subsidy for “efficient AC units” a while back and it actually increased electricity consumption because the more “efficient” units are designed for very large rooms, vastly larger than the rooms that most Taiwanese are using them in.

A 1 ton AC should be more than enough for a medium sized room (6-10 pings) and anything larger should only be used for living rooms or commercial space. Shops should design their space so that it’s not so open, so they don’t waste electricity blasting cold air into the street.

Nice post TL. Maybe you could turn your hand to AC maintenance. :bow:

Hanging 200ft in the air to install AC units and dealing with freon? no thanks…

This was never intended to be a fixation on 25 degrees C - the point is that the unit waivers and the temp mentioned was just an example. It fluctuates around -2-3 degrees from that, and that’s the problem. Of course I’m not making a blanket generalisation for the correct temp for all buildings in Taipei throughout the warmer months. Sorry you latched on to that so.

It is a studio apartment, quite small, not medium-sized. Not sure in terms of ping, but it is Gongguan, across from NTU, basically a student apt, like a small dorm room. So in that case, what size/type of AC unit would be required to maintain a constant - but not iceberg cold - temp. It would be useful to know what the Chinese term for “inverter AC” is. Please suggest.

You need a 8000 btu Ac that is probably about one ton. Anything larger is a waste of electricity. You will not find inverter units that small.

TL, are you suggesting that these inverter-equipped 8000 btu units truly don’t exist, or rather that they are uncommon? Needing to arrive at a more definitive answer on the smallest inverter-equipped units, and any possible government subsidies for landlords installing efficient AC. Obviously, a larger than needed unit works against all of this.

24h.pchome.com.tw/prod/DPAF3I-19 … =/S/DPAF3X
24h.pchome.com.tw/prod/DPAF3I-19 … =/S/DPAF3X

Sorry I havent looked at AC’s for a long time, when I looked a while ago all the inverter units were at least 2 ton or something, or at least costs quite a bit. I see things have changed. But like I said you don’t need anything bigger than 1 ton for such a small room… in fact it can probably do 2 of those rooms… To truly save energy you just want to lower the temperature a little bit while removing humidity.

Yes, things have changed. These are 8000 btu units, inverter-equipped, suitable for 4-6 ping. Taiwan might not need another power plant if the island could curb its absolutely inane air conditioning habits, frankly. The number one energy draw in any home can always be traced to items which either cool or heat i.e. AC units, water heaters, refrigerators, etc… The technology is there to cope with this. A major urban challenge worldwide in this day and age is how to handle growth and the attendant energy demands. Taiwan should be “all over this”, as it’s had to deal with density for a long time and it’s a tech-savvy nation. Pay more upfront and reap in energy savings that will more than offset the iniital additional cost - though one has to think more than 6 months ahead. The all too common mentality, the short-sighted “that’ll do for now” is a kind of public enemy.

The government tried to offer a subsidy on efficient air conditioners in order to encourage people to switch to a more efficient unit. Unfortunately at the time all the efficient units were rather large and people bought them for rooms that are way too small for them. It ended up increasing electricity use. Some people might think “bigger is better” but when it comes to AC sizing, you have to take into account the size of the space and the number of people expected to occupy that space. For example a 10 ping room might require a 1.5 ton AC but if the room is occupied by 10 people most the time it will require a 2.5 ton AC.

[quote=“silas”]This was never intended to be a fixation on 25 degrees C - the point is that the unit waivers and the temp mentioned was just an example. It fluctuates around -2-3 degrees from that, and that’s the problem. Of course I’m not making a blanket generalisation for the correct temp for all buildings in Taipei throughout the warmer months. Sorry you latched on to that so.

It is a studio apartment, quite small, not medium-sized. Not sure in terms of ping, but it is Gongguan, across from NTU, basically a student apt, like a small dorm room. So in that case, what size/type of AC unit would be required to maintain a constant - but not iceberg cold - temp. It would be useful to know what the Chinese term for “inverter AC” is. Please suggest.[/quote]

All A/Cs cycle, it’s just a normal part of their operation. An A/C unit that is running builds up ice on the evaporator coils because the coils are below the freezing point of water (touch them with your finger and your skin will stick :astonished: ).

The more humid the ambient air and the slower the fan speed, the faster the ice crystals will grow.

If the A/C doesn’t cycle (periodically drawing ambient air over the coils to warm them), then the ice will just build up until the airflow is blocked off completely.

All ACs cycle, yes, however a modern, properly designed inverter-equipped unit and of the size that correctly matches the area its serving should perform vastly better, saving energy and money. Taiwan wastes enormous amounts of energy doing AC the wrong way. Five years ago, the inverter AC units, particularly in the smaller size as TL has pointed out, were quite uncommon, and led to mismatched larger units being installed which ultimately may have backfired. Now they’re available.

Yeah, I meant to say all traditional A/Cs units cycle.

“Traditional” ACs will be phased out - they’re immensely wasteful of energy and represent an outdated, backward, short-sighted approach. The island can’t afford this nonsense, not from an energy capacity standpoint, nor an environmental standpoint, nor even a bottom-line economic standpoint. It becomes vastly more expensive (when factoring in all costs - including building extra capacity) to continue down this path when energy demands are rising in other sectors. In a few years, incandescent bulbs and invertless ACs will be very uncommon.

It’s easy to bring change, just raise electricity prices, which is what has been happening,

Correct me if I’m wrong but the temperature of air teh an AC spits out is a flat 18 degrees…if you set 25 that’s not the temperature of the air being expelled its just the thermostat temperature so the unit will turn off once it senses the ambient air temperature is 25. Hence the constant cycling around 23 to 26. The reason people set the thermostat as low as 20 is that dead spots in a room where the air flow doesn’t reach will remain near 29 degrees. Anyone living in a rooftop will also need to set the AC low, because the room will super heat due to constant direct sun on the external structure.

Not with the inverter A/Cs.

Regardless of housing type, whether an ‘illegal’ hot tin rooftop flat, a poorly insulated flat, or anything else, ACs without inverters are a major waste of time, energy resources, and money. Their ability to perform with any efficiency can be compared to a combustion engine car without a transmission – a transmission exists to efficiently maximise the motor’s output. Imagine the gas mileage that would result in a car with just a single gear, comparable to say 2nd gear, running on the motorway. Such a car would be easier to manufacture and somewhat cheaper. That’s been the model for AC common in Taiwan, up until recently. It’s the equivalent of a polluting 2-stroke engine, and should be bloody banned.

An update: the landlord and I came to an agreeable arrangement where I am reimbursing her for part of the additional cost of a new, energy efficient inverter-equipped AC. It’s just been installed this week, well before the summer heat moves in. At the same time, we were looking to replace the refrigerator as well, and this is the model the landlord wishes to use: 24h.pchome.com.tw/prod/DPAC0W-A73315173

I don’t have a favourable impression of it. Can others who read Chinese comment on the info presented - how is this unit’s energy efficiency depicted? Thank you.