Could be from an overly strong plasma ionizer function? Does it have UV? I know I'm sensitive to that for too long. How cold you set it?

OK thanks for confirming this observation. Wonder why the Sharp AHXP10V plasma in my kids room no maintenance after 3 years clean except for grill.

Three things that made me consider the Sharp are:
1. Gentle cool direct air towards ceiling which when combined with fan at 1-2 speed only require AC operation at 28 degrees even on hot days. Wind chill effect with fan brings it down to 27 and some spots 26. All this verifiable with indrect point and scan thermometer like what they use at airport arrival terminal. Just scan on bed surface.

2. Self clean - dries the condensing unit plus plasma cluster reduce mould growth.

3. R410A (Puron) gas has better efficiency giving high COP. R22 only can get 40% at most (Daikin newest generation R22 inverter FTKDnnGVM) while R410A higher.

Also a health lesson I learned from my friend in SG. Never leave AC below 27 for esp children. It dries up their lungs really fast and they get asthma very easily. Same goes for older adults. Just leave it 27 with low speed fan. No need for humidifier - our climate already so humid why encourage mould to grow in room. Best combo I discover is AC with sleep mode with fans like Panasonic Bayu or Nami (or their KDK equivalent) which also has sleep mode up to 8 hours max.

Different cassettes model have different chassis height based on HP. 2-2.5HP falls between 22-28cm height. Anything more than 2.5HP typically range from 27-30cm in height. There are slimmer cassettes with 16-23cm height but those are not in this market yet.

For cassette, my take is the ceiling height 11' minimum with a 40-50cm drop for allowance in clearing beam height in situations where beams criss-cross installation location. Meaning that for some locations with beams criss-crossing, the pipes have to clear beneath the beam so the drop must accommodate that. The crucial one is the water outlet which usually goes to the nearest possible outlet either an outside wall (easiest) or toilet. The drain pipe must drop in a gentle slope and hence they don't necessarily have to be drained where the compressor is if it's not the nearest. So the false ceiling must take drainage slope into account.

The 1hp traingle design Samsung even for non-inverter is a whopping low 690W. First time coming across 1hp non-inverter (R22) that is rated that low wattage. Normally between 830-900W depending on make and model.

This post has been edited by halcyon27: Mar 24 2014, 08:46 PM

9000BTU for R22 Non-inverter. Compare here

Note: The 1HP of Samsung triangle at least has max length of 15m but max vertical height difference of 7m. Perhaps this is to be carefully noted. The Daikin 1HP has max piping length of 25m but max height difference of 15m. Not that it matters unless in certain circumstances where AC piping length is really really long and shorter installation is not possible due to building maintenance policy esp where there is a lack of out of building AC compressor placement bays.

This post has been edited by halcyon27: Mar 25 2014, 12:00 AM

Ummm... unless the room is ground floor and is very shaded or very good insulation material (like AAC bricks) then yes 1 HP good enough

However, 4m = 13.12 ft so calculating L=W= 13.12 and hlf=70, this gets:
LxWxhlf=13.12x13.12x70=12050BTU

That is somewhere in the league of 1.5HP ac.

hlf is heat load factor and usually varies depending on landed or condo, room orientation (facing which compass direction), dwelling placement (intermediate, corner) and orientation (front facing <compass direction>) and whether first or ground floor or for condo have floors above it or direct under rooftop.

I have written about this before (see post#4).

Even for a room that is perfectly size for 1HP but because using incorrect hlf then it could be underpowered for that room.

This post has been edited by halcyon27: Apr 1 2014, 10:38 PM

hi steventan85, it's not complicated but the assumptions have to be laid out case by case. If your room is same size as seongmeng then perhaps your dwelling could be better insulated to arrive at 1hp. Conservatively, I'd say otherwise.

Experience borne out for me and this formula is tried and true in our climate. Even smaller size room but because it faces south and no neighbour behind but main road, ac work frequently into the night to achieve set point.

Assumptions:
A. Wall is clay masonry brick or sandbrick- this one contribute high heat mass - oven like in the night. This is the constant factor prevailing and unless specifically using AAC fugedaboutit. AAC halves heat load ie what normally is 2HP for living room, 1HP pun cukup for 22x16 living room.
B. Ceiling is not higher than 10ft
C. Roof - little or no insulation even if have also contribute to storing heat (esp cellulose) in the night.
Aluminium foil with membrane sealing (foil not exposed) - Monier, Parsec Thermobrite, TCM6 can minus 5 from hlf
Those without ie exposed Aluminium will lose efficiency quickly it's installed as the dust will inhibit its radiant heat
reflectivity
D. Air tightness is average - meaning cold air leaks easily esp into toilet and room door - those Raven door rubber seal helps slows that down so can minus 1 or 2
E. Window type - double or triple glazing helps but more important is if it's casement sealed or louvre. The latter can leak cold air out unless using brand like Breezeway or Altair.
F. Outside ground - cemented or soil garden with foliage. Cemented ground acts as a heat bank and will reradiate stored heat esp the air of breezes that blow in. The ambient air may be cooler at night but the immediate ground can feel warm. Sometimes completely sealing without a break/gap can conduct the heat inwards. Unless when cementing the ground is with old tyres - like how Smartcool does it.

But assumption A and B is almost likely the common factor across much of the dwelling in this land on average. The outliers being living on a high hill or very heavily shaded naturally or construction wise.

Try this calculator here, which is close to what I calculated except that it's more generous or less depending upon afternoon sun with or without curtain, etc.

This post has been edited by halcyon27: Apr 4 2014, 12:14 AM

PJusa you nailed the assumptions rightly in your first and last paragraph. I agree with you in whether it will cool and prolong the cool or the compressor would cut in frequently to maintain the cool.

One thing about cooling often discussed is that it's focus on area (LxW) and indirectly volume is taken into account but what is crucial is the heat load imposed by the structure (walls and most often times ceilings). Condo units are much easier to cool given that above and below are air space insulation unless of course it's top floor. It's not so much about area or volume in that situation. It's about how much heat is being removed and how long before it reaches equilibrium.

Daikin R-410A with hot water. Product called Hot Water System

This post has been edited by halcyon27: Apr 6 2014, 12:20 AM

The Sharp plasma cluster equipped aircond are really good. I use an inverter model in my kids room and set it to 28 on most days with 1 speed ceiling fan. 27 on hotter and 26 if hotter still but with ceiling insulation that's not necessary. Sleep mode is a feature I would like to see as the early mornings are already cold at 26 or 24 degrees depending on season. Basically it's on to keep humidity low. Too cold would be too dry. 28-27 is ok for little children esp infants. Any lower is asking for trouble as that would induce lungs to dry faster and cause them to get asthma.

This post has been edited by halcyon27: May 12 2014, 09:26 PM

Bro, don't misunderstand but night time temp at what humidity outside vs in the room whose walls are already storing heat and re-radiating it into the interior is what needs to be considered. I slept with a table or stand fan for over 30 years and even on cool nights outside, the heated air and humidity in the room prevents cold air from coming in. It's like an oven. Different story if house shaded by trees and have running brook that cools the night air. Places like this the sun light hardly hit the ground there's little or no excess stored heat. Humidity different story.

Edit: Insulating bad idea if heat is not removed. That comes from residual heat (no insulation is 100%) building up over time. That means the convective hot air needs to be evacuated. That's why combining a good radiant barrier (that would not lose its reflective properties) with a turbine ventilator is the proper way. If still too hot then it's orientation and surface shading has to be considered. That's why they say plant a tree.

This post has been edited by halcyon27: May 12 2014, 10:10 PM

The conclusion of the matter is that humidity is the main problem here - too much or too high of it heat cannot dissipate very well be it man, animal or machine. Some weather sites like Accuweather describe it as RealFeel - ground ambient could be X but with Y humidity it feels like Z. So aircon still has its uses to cool and dehumidify. The art is in adjusting it not too cold and too dry as how many of us abuse it esp without knowing the ramifications for children. For that 28 deg and 1 speed ceiling fan is more than adequate even for an infant in fleece blanket. Since they don't sleep outside where it's much colder and would risk exposure to the elements and mosquito but their rooms bake throughout the night until 3-4AM, AC does the job nicely.

Older houses needed to be considered in the context of what are the surroundings. Does the occupant grow trees or have a garden? That slows the heat accumulated compared to bare concrete or totally non-gardened dwellings. But it would be folly to think that the physics of heat mass would act differently from clime to clime in relation with humidity. Brick does very well in hot day and very cold nights in a low to mildly humid clime. The heat retained is re-radiated to the benefit of the occupants in the night. But simply not here where humidity is high. It can't dissipate effectively enough until after 3am. Anytime between that an AC helps dehumidify and extract the oven like heat.

Cross-ventilation has its purposes and is good practice to use in this climate. Your description of how it works actually only works with wind and possibly louvered windows (best air inflitration performance from any wind direction) if the air inside the house is cooler. I use that with extractor fans, turbine ventilators. I used it to its maximum advantage during rainy season but not when it's blistering hot - that's where the urban heat island effect phenomena comes into play. But all's not lost since the best time to use it is early in the morning like 4-5am when they are timed to turn on until 7am - brings the cool in and it stays cool until 2PM.

Also, placement of rooms in relation to surroundings should decide if the occupant wants to breathe clean forest refreshed air or street air. I heartily agree with your assessment if their room faces green lungs like FRIM, etc. Unfortunately for my kids, the latter is their situation so it's case by case. For such a Medklinn and a Sharp Plasmacluster (inverter) helps in this situation.

end users won't know the cause of it unless they work in this industry. For that a very good and honest AC installer expert diagnosis is required.

Something new to learn. Although R410a has 0 ozone depletion potential compared to R22's 0.055 relative to R11 (ODP @R11=1.0), both have high green house warming potential (GWP) relative to Carbon Dioxide. R22 at 1810 and R410a at 2088 relative to CO2 (GWP @CO2 = 1.0).

There's supposedly a classes of refrigerant out that addresses GWP:
R32 0 ODP but 675 GWP
R1234yf 0 ODP and 4 GWP
R290 0 ODP and 6.3 GWP

See this link.

This post has been edited by halcyon27: Jun 2 2014, 04:04 PM

May or may not be the product design but the difference in height between the AC pipes and the drain outlet pipe. If you're in Klang Valley, I can recommend an installer to have a look. He's an eye for detail and minor stuff like this he can point out if it is truly an piping works issue.

I kinda dislike the foam insert as that would mould over time but maybe the Sharp technician is relying on the plasmacluster to do its job.

The 1.0 HP inverter Sharp plasmacluster model AH-XP10LV in my kids room hardly have filter dirty at all since its commissioning in Oct 2010 and they don't have dripping noises. I use the Clean function after every use and even the cooling fins are clean since all these years. Only thing it needs is a compressor maintenance.

PMed you the contact. Let him have a look and you decided based on his findings.

In most cases, it is not about the length to the outside compressor but the height of the exposed refrigerant piping and drainage piping in relation to each other on site (where the blower unit is installed).

Yes, at times I use the Low Wattage function. I only use 27 deg max in combination with 1 speed fan.

This post has been edited by halcyon27: Jun 16 2014, 01:19 PM

Inverter for bedrooms or any space that consistently requires greater than 6hours of cooling. Non-inverter for any short or spot use cooling for short duration (1-4 hours).

Heat load determination = L x W x hlf= Area (in sq ft) x hlf = heat load in British Thermal Unit (BTU)
Use the resultant BTU calculated to determine what AC horsepower to get.
hlf depends on room orientation, if there's external shading over room, if insulation is present.

Base conservative head load factor (hlf) typically is:
60 for condos and ground floor
70 for upper floors beneath uninsulated roof
75 for top unit of condo/apartment.

All this assumes 10' ceiling height. If ceiling is low like 8-9' then -5 from the base.
If ceiling is higher than 10' but less than 15' then add 5 to the base.
Mostly the base numbers are constant assuming that 4" thick clay masonry bricks are used for construction.
8" thick clay masonry bricks can -5 as there's more thermal mass it can contain. These type of bricks tend to make the house feel cooler.
AAC has thermal insulation advantage that allows 50-75% the base of the heat load factor of 4" masonry brick.

HLF Modifiers (+/- to base hlf):
+5 if sun facing area is W,SW or S and has larger than usual fenestration (windows)
+10 if room wall faces W,SW or S (typical corner unit)
-5 for shading or roof envelop insulation
-10 Mostly shaded (facing high mountain directly behind with lots of high trees or just behind is jungle or another overly tall building)

Take a typical north/northeast facing DSH intermediate with gross build up of 22x70 ground floor living room (20'x20') and first floor MBR (12'x15')
Assuming dining and living is zoned w AC
Living room = 20'x20'x60=24000BTU.
Upper floor MBR with uninsulated concrete tiled roof = 12'x15'x70=12600 BTU

Look up any AC spec will reveal that a living room and MBR of the above size requires 2.5HP AC and 1.5HP (BTU at upper limit of typical 1.5HP of 12,000-13,500BTU). If in doubt, try turning the MBR in the day time at AUTO mode and see how long before temp reaches pre-set and compressor idles again. Modern 1.5HP AC esp w inverter would have power mode that strecthes from 12,000 to 14,000BTU depending on make and model.

Again the numbers are a rough guide. Cooling is acheived faster when the heat load is low esp during raining but the stored heat from the roof and walls will radiate inwards until 3-4am when everything is cooler like outdoor again but the trapped heat unless dissipated may still cause the inside to feel hot without AC cooling.

This post has been edited by halcyon27: Jul 7 2014, 08:01 PM

I read the paper through the link you posted. While I agree it's findings, it has to be interpreted in terms of the same volume of refrigerant. What I interpret it is at equal volume, R22 still ok even at higher outdoor temperature. What the refrigerant engineer have done in practice is to increase the R410a volume to compensate for the critical temperature in order to yield similar or better performance. Hence this refrigerant operates at a higher pressure than when using R22.

There are also newer refrigerant out there in an earlier posting that does not contribute as much as green house gas effect as R410a as well as ozone depletion.

Sharp's new model seems to also reduced power consumption from 800-900W to 690W. Think the trend is large air intake to increase cooling efficiency. BTW, the Daikin and Mitsubishi also have ecoNavi like feature. It's an infrared ball thingy that scans the room and bring up temperature if there's no occupant. But they may not work as well as ecoNavi's fuzzy logic.

PMed you.