Hi All, just want to share my experience. I came across one air con installer named KW Mega Aircon and his boss name is Lim. First he send one guy and do site inspection. After that i received quotation from him and price is quite attractive. I do compare with others contractor but seems this Lim price is quite competitive then i decided to award to him. When work started then nightmare came. His worker complained my wall is too hard because got metal reinforced and not normal bricks then asked for additional cost. Also then water piping run too long and need addtional cost. In fact his first guy already inspected the site and should already included in the quote and how come all this hidden cost come later? I just wonder will he charge me later when the compressor is heavy than normal one? So guys, please beware on this contractor and his boss is speak nicely when ask for your job. Thanks.

Hi tlcm5229, your dwelling type landed or condo?

This post has been edited by halcyon27: Aug 1 2017, 10:32 AM

Hi gengar77, questions you need to ask to assess based on an older AC thread post
1. What's above the unit at the top? Is it another floor e.g. water tangki, sky terrace, bare concrete cement roof or tiled roof or metal roof?
2. Each room orientation where the AC will be installed (all applicable compass points where the walls are exposed and does not border a neighboring unit)
3. Area (LxW) of each room to cool and their ceiling height
4. Semi partition movable (sliding doors) or fixed (wall or tall bookshelf)

Based on the post linked above, calculate the cooling load in BTU which serves as the starting point of what kind of AC HP to get. Being at the top floor, depending on what is above it, sometimes the heat load is increased by 20-30% which means a 1.5HP or 1.75HP will be required. Only Panasonic sells 1.75HP (15,000BTU) but the piping for such is 2HP already.

As an example, say a 5m x 3.5m bedroom on the second (any floor except the top) floor of a multiple story condo. It has large windows facing south on one corner and south west on another.
Total area (A) = 188.368sqft (17.5m2)
Base HLF (Hb) = 60 _____for condos and ground floor
Additional modifier:
+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)
Final HLF for this bedroom (Hf) =75
Cooling load required= A x Hf = 14,128BTU

On a clear sunny day, this bedroom will bake her occupants through the night until 3am.

Had the bedroom faced east and the windows are no larger than 25% of the whole wall exposed, it's cooling final HLF would have remained unmodified at 60 which yields 11,302BTU.

Of course, curtains block out the sun and double glazed reduces the heat load.

One more thing: for the same AC pipe diameter, 1 and 1.5HP are interchangeable. 1.75 and 2HP are compatible for 2HP pipes. Some AC units 2.5HP also fits on 2HP. The key is the return (gas phase) pipe diameter. Typically 2.5 or 3HP and above a larger gas pipe diameter is required. So sizing is important if the calculated load is bordering on the next HP which may or may not affect the pipe diameters required and thus expanding or limiting the choices when an upgrade is required. Mitsubishi Electric is one anomaly in which it 2HP typically uses a 2.5HP sized return pipe.

Hope that helps.

This post has been edited by halcyon27: Aug 1 2017, 11:23 AM

You should immediately ask him to stop the job.

Make it clear before can continue. Otherwise terminate the job and get another.

hi all ,

need your opinion/thoughts on the following air conditioners, and which brand is better/recommend to buy???

single wall split

Daikin - Qseries (R410A refrigerant)
1.0hp - Daikin FTK15QV1L
1.5hp - Daikin FTK10QV1L
2.0hp - Daikin FTK20QV1L


Panasonic - Premium Inverter (R410A refrigerant)
1.0hp - CS-S10SKH-1
1.5hp - CS-S13SKH-1
2.0hp - CS-S18SKH-1

Hi, I would like to buy Mitsubishi Electric Air Cond but noted that it has 3 types of refrigerants:-
1). R22
2). R410
3). R32

Which one should I go for in term of repairing. servicing (easy to get the spare parts), stableness(no easy to break down) and quietness(the compressor not running noisily)?

This post has been edited by firee818: Aug 3 2017, 09:12 AM

R410

both brand is good.. no worry

R22 phased out
R410a is current
R32 is newer but also mildly flammable but then again the trade requires all technician to be trained to handle the refrigerants used.

Btw R410a is 50% R32 and 50% retardant that makes it safer but at the expense of cooling efficiency. A pure R32 unit cools more efficiently than a R410a unit. As they are new, gas may be scarcer hence more expensive. Also the AC units are also more expensive vs R410a units.

ah i see. thanks thanks

but based on the models/series i chose, which is actually the better choice to buy?
if its you

also how about the after sales service like? which is cheaper to service? parts easier to find?

This post has been edited by blackwhitebear: Aug 3 2017, 09:52 AM

actually both are equally good in terms of quality, reliability, service, parts..

i have both panasonic and daikin, but daikin is very-slightly quieter.. though panasonic doesn't really bother me much.. it is not like a big-bang-loud-sounds.. so actually nothing much to worry..

so if u ask me.. i will go for cheaper price for this both brands (for the same spec)..

The most reliable brand I've used. Still have one 16 yo unit in my bedroom and a 24 yo unit in another bedroom. Used daily. Never broke down once and never serviced. Just DIY cleaning. Compressor and indoor unit still quiet

the models that i chose from the 2 brands are same spec, right?
sorry im very noobish about all these haha

correction:
daikin FTK15QV1L = 1.5hp (not 1.0hp)
daikin FTK10QV1L = 1.0hp (not 1.5hp)

anyway, both model.. more of less the same tech..

ah yes models typo haha.

ok thanks for your help have a good day!

Hi,

Thanks for the great details.After calculation 2.0HP should do the trick as my unit is on the top floor and above is bare concrete cement.
Would it be better to get a single 2.0HP unit or 2 units of 1.0HP and have each placed at the front and back?This was actually suggested by the sales person.
Which option will cost me more to run?

Thank you.

It depends if it's easy to isolate the zones such that each one can cool it down without being overtaxed. I'll prefer this approach too. If you think it might overtax then go for 1.5hp at the crucial one like bedroom. One easy way to partition is to use thick curtains.

Three things to consider:
1. Piping insulation. Individually sleeved per pipe. Use Inaba Denko's (JP) or Smartco's (KR) Paircoil. Sets you back a bit but guarantee will not develop leaks so long as installed correctly. Use 0.8" thickness for R410a which is also compatible with R32. The requirement is to guarantee AC runs at its rated power without which (all in one jacket/sleeve), the mixture causes the compressor to overwork (higher electricity consumption than rated) which can potentially damage the indoor unit cooling fins esp if the piping runs are in excess of 3m. This is evident when there's freezing on the AC cooling fins due to this caused by the compressor overworking to compensate for inadequate cooling capacity. You'll know when you hear the sudden tak tak sound of ice forming and bending the fins. Leaky pipes can also cause this over time. Quite common in old AC but not sure perhaps they've mitigated this now.

2. Piping size - it's ok to oversize such that in future, if you need to upsize, there's no need to hack and repipe. Bear in mind the gas / return / hot pipe should be equal or larger, never smaller than that of that AC model used. For example, 1.5HP on a 2HP pipe or 2HP on a 2.5/3HP pipe. If experience bears out that a 1HP or 1.5HP cooling is insufficient, you can in future swap that out and get a 2HP but without changing pipes.

3. Long air throw. If relying on a single, bear in mind that certain AC have what's called long throw feature like the Sharp inverter (14m even on a 1HP) or a Mitsubishi Electric Mr Slim. The Sharp has a ceiling throw mode for gentler cooling too.

This post has been edited by halcyon27: Aug 4 2017, 02:24 PM

My Panasonic 1.5p non-invertor compressor is spoil. If changed by panasonic authorised contractor need RM450 (but heard from fren, with this price, then it might be second hand). Anyone has experience?

How long used before this? Is there any error codes thrown?

Authorised give you 2nd hand spare part?

If 3rd party, I would believe.