AC specs looks good , price good too and with 3 years warranty I think can try .

Let me rephrase it. For our residential use with TT earthing, you should only use L-N & N-E SPD. You should not use L-E SPD. Unless it is monoblock SPD, you can easily identify the connection type based on the what pole is on the opposing side of L (Edit: for cheapo brand that won't spend extra for internal routing. Most of China oem design is such). You can check local brand such as maxguard and duval for example. Other brand may even allow to to swap N with E to change the connection type from CT1 to CT2.


Just Google SPD CT2 and if you have access, refer to IEC 60364-5-53. SPD can a be safety hazard when failed if installed improperly. Not everything are suitable for general residential use, let alone installed by non-professional.

This post has been edited by jio: Aug 14 2024, 11:44 AM

Actually this older model is 1181 Joules while the newer one is much lower at 306 joules but costs very similar which is very weird.

ok .. 1181 j is great

This is my aircond list. The living, dining, kitchen, are all connected as seen in the floor plan. It's about 12.3 meters in length and 6.7m in width so about 82.4 sqm or a hair under 900 sqft.



The orange circles are where we intend to put them. We can't put them on the shortest beams because we've got light fixtures on the beams. It's inefficient but I hope, still effective enough.

The dining, living, will run in 8 hour intervals except when we're sleeping in which we'll turn them off. The kitchen ac will be turned on to assist if it gets too warm as that's the most powerful one.

We've an earth tube that's placed 1 meter underground and rigged it through an ERV + a whole house dehumidifier to move air from the outside and hopefully by the time it's chucked into the house, it's cooled down and drier.

The plan is to keep the house at or below 24c and humidity around +-55% at all times.

My question is, based on the conditions built, is this a realistic expectation from my ac? I'm going under the assumption of 20 btu per square feet which assumes I'll need 18,000 btu. I'm getting the 22,500 btu and 30,000 btu ac's to account for the insane heat Malaysia's been smacked with.

Our ac compressors are also underneath the eaves to avoid being in the sun and we've got plants flanking the compressor to hopefully cool the area.

Also, we're getting daikin and mitsubishi because everyone keeps repeating that these two are the best, and also the worst. So we figured we'll just get both and try.

This post has been edited by pizzaboy: Aug 21 2024, 05:41 AM

Nowadays still planing on non inverter aircon?
Singapore non inverter already discontinued more than 15 years ago. I suggest you get inverter instead. Except for dining and living area can remain as non-inverter. The rest go for inverter more comfortable and energy saving.
Unless you plan for rental out the whole unit.

Double storey terrace house the minimum 6 units.
Any brands are the good , for sure is inverter and do vacuum pump for all unit before done installation.

This post has been edited by Benefon: Aug 22 2024, 07:31 AM

Earthtube, ERV and dehumidifier? sounds expensive as its uncommon practice locally, but interested to find out more on your setup to reduce active cooling.

Hi, may I ask the sifus here, if the house has solar which can generate adequate electricity, is inverter aircon still necessary or a waste of money? Am I wrong that my thinking is inverter is to same electricity?

Nah, it was quite affordable. We had to dig the ground to put the sewerage and foundations anyway, so it wasn't much more to just chuck in a bunch of ceramic tubes. Dehumidifer and ERV, we bought from China so we skipped the middleman. So all in all, I think it cost us an additional RM6,000 only. There's actually a house in Melaka, that has built this.

https://www.cooltek.org/

The ERV and dehumidifier is a more recent addition as we get skin issues from the humidity of the air. But yeah I'll keep you updated.

According to my HVAC fellas, to answer your question, no it's not a waste of money. But it's very use case specific. Large areas like ours, where we have 2,500 sqft of open connected areas, there's no split inverter that can cool down that space, except VRV units. So they said in that case, might as well just use non-inverters.

Also we calculated our panels production which is 14kw/h system, so we make about 2,100KW a month. We definitely do not use 2,100 kwh a month

But for rooms, they still said inverters would be reasonable. But we've oversized our inverters by 0.5hp just for contingency sakes as we sleep in 18c.

As to why we won't use VRV units, it's because we've used them in the past, and they're a massive headache when it comes to servicing. Our servicing bill was RM18,000 a year because the house was quite big and we had the ac on 24/7. Since we're retired now, and downsizing we just don't want any more headaches.

Thanks forsharing. VRV will be too costly and impractical for us too. Will consider inverter see how the budget and price.

how long does an aircon can cool down to 25 degree is considered 'normal' for its cooling capability?

for room aircon which u are using every night, i highly recommend to use inverter, not only it will save electricity but most importantly, u will feel the constant temperature throughout the night comparing to non-inverter one..
it will be much much much more comfortable for sleeping...

Non inverter not so good at maintaining a fixed temperature? Wonder whether if have solar, the extra electricity generated during day time can offset energy use at night.....

Hey man, how do you tell the temperature is more constant?

For context, wherever I go, I always keep it at 18c, and I run it at full speed. I have never been able to tell when it's an inverter or not an inverter AC.

Good condition aircon , normally will set on 24-23c with fan speed 1-3.
Lower than 22c mean highest usage energy also very dry humid.
Unlike your are plan to build server room, keep it on 24 hrs and 18c all the time.

The bad thing is condensation, also aircon maintenance with high bill on non - inverter unit, the operation super annoying to make the outdoor compressor on and off, while the rubber mounting vibration and fan motor spoil much faster than what you are expectation

Anyway good luck for you.
18c with full fan speed with non - inverter setup

inverter will have the compressor run at lower power to keep the temperature set while non-inverter once reach the set temperature and compressor will stop immediately and once room temperature goes up beyond the set temperature it runs at full speed to reach the set temperature again... and this cycle will continue...
so u can imagine, u will feel the 'change' in temperature inside the room all the time, and ur aircon will be noisy when it runs at full speed for fans...


obviously u did not know aircon by setting ur aircon to 18c.

25/24 degree celcius should be the most comfortable temperature for most ppl to sleep at nite... and it is easier to reach the set temperature given the outdoor temperature at night. 25 degree for my mitsubishi non-inverter aircon it takes about 20 minutes to reach while on at nite... 24 degree will need at least another 10 more minutes.. anything lower than 23 degree will take even longer, and the time taken is not proportional normally... as the set temperature is further away from outdoor current temperature it takes longer to cool down to that set temperature and worst case scenario is that it will never reach becos the set temperature is way too low... typical aircon that has the BTU matches the room size can never hit 18 degree so the compressor will be running at max speed and consumes the max electricity as possible..

so it is totally silly to set the temp at 18 degree...

Haha, I guess for those ppl set on server room, the temperature super high.
Set on 18c just a preference only. Basically 24-25c very comfortable for inverter unit.
Anyway please do vacuum pump when during installation.
R32 gas very sensitive.

After complain to Mitsubishi Electric customer service.
The installer come back do vacuum pump for us.
They need release all the existing gas and pump then refill all new R32 gas.
After done, set on 24 or 25c just an hour to cool down 3x5m master bedroom, otherwise it is keep whole night to light off dual led indicator from FCU.

1 hour just to cool down ur master bedroom??

it means ur aircon BTU is not sufficient for ur room size...

Oh no, I'm not planning to build a server room. It's just that our rooms are usually set at 18c because this is what we're most comfortable with. Back in the UK, 18c requires the heater to run whereas in Malaysia, it's the AC that ends up having a rough time. So we ended up with a VRV system for our previous home but that's a lot of work to maintain. I'm pretty sure the VRV system was an inverter system, but we've sold that house to downsize to the current one.

We're also installing the inverters for our bedroom. So hopefully that works out and doesn't require too much maintenance.

Thank you for the good wishes. Much appreciated.

I see

Let me clarify and see if I understand your messages;

1. It's the stop-start cycle that enables you to notice the difference in inverter and non-inverter AC operations. This is probably why I never noticed the difference in most of the places I stayed in.

2. Most AC with BTU that matches the room size will not achieve 18c.

For my setup, our room is a small 4.5m x 5.4m room with 13 feet ceilings. Our rated BTU required was something like 18,000 at 18c. So we've oversized it to the FTKM60TVMM which is a 4000btu - 24,200btu unit.

Considering this, would it still be a tad silly to expect 18C for my unit? If it is, I could install a second unit as it's quite important for us to sleep comfortably in Malaysia. Or I could upgrade the unit to a higher BTU unit too.

My circle of competence is so far removed from this that I haven't the faintest clue how best to approach this. Speaking to my HVAC guys have been quite enlightening but you seem to have a lot of knowledge in this field.

I appreciate you taking the time to comment and help me find a better solution before I bite the bullet on this. The hacking for the piping would be such a hassle so I'd rather know, before we cast the walls.