Air conditioning - Any recommendations please?? - Part 2

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Only reason I suggested 3G28VA2 is because the savings between 28VA2 and 38VA2 is considerable enough for a reasonable compromise for when they run the 3rd BR FCU on rare occasions. The 3G28VA2 is still able to supply the 2x BR's FN10s at full capacity.

Still, I wish ME continued having the 2-tick range. The stupidity of chasing 5-ticks while compromising cooling capacity AND charging more is nothing more than an easy money grab by ME. The old 2-tick entry level 3A28VA (25.5K) has more capacity than the 4G38VA2 (25.2K). Combined with crappy aircon salesmen, we get the mess that we have today.


Yep. Prices based on GC:
4G38VA2 (sys3) + GN18VA - $6240
3G28VA2 (sys3) + GN18VA - $5430
3G28VA2 (sys3) + GN24VA - $5670
4G33VA2 (sys4) - $4380
4G38VA2 (sys4) - $4960

Though you could scout other aircon contractors. I remember mine quoting me $1.8k for GN24
Didn't know choosing aircon is so complicated.

Now really have to think if I will ever use all the aircon at the same time. And even if I do, will the reduced cooling be enough? Or will it just take a longer time to cool down the room?
I'm willing to compromise if it just takes a longer time to cooldown. Afterall, I won't switch on all aircon so often unless there are guest at my house.

Also, I think you guys missed out on one of my questions. Appreciate it if you guys can give advice.

My living room is connected to the kitchen and a walkway to the bedrooms. Do I need to account for those areas when calculating the BTU/hr needed?

Area that I need to be cooled: 17.5 sqm
Living room ONLY: 25 sqm
Living room + Walkway: 29 sqm
Living room + Walkway + Kitchen: 39 sqm



Highlighted green is the area that I want to be cooled.
Highlighted red is the area that is walking past only.
Highlighted blue is the location of aircon.
 

batniss

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Didn't know choosing aircon is so complicated.

Now really have to think if I will ever use all the aircon at the same time. And even if I do, will the reduced cooling be enough? Or will it just take a longer time to cool down the room?
I'm willing to compromise if it just takes a longer time to cooldown. Afterall, I won't switch on all aircon so often unless there are guest at my house.

Also, I think you guys missed out on one of my questions. Appreciate it if you guys can give advice.

My living room is connected to the kitchen and a walkway to the bedrooms. Do I need to account for those areas when calculating the BTU/hr needed?

Area that I need to be cooled: 17.5 sqm
Living room ONLY: 25 sqm
Living room + Walkway: 29 sqm
Living room + Walkway + Kitchen: 39 sqm



Highlighted green is the area that I want to be cooled.
Highlighted red is the area that is walking past only.
Highlighted blue is the location of aircon.
of course, you need UNLESS it is covered up (with a door, window etc).
 

yahoosoda

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just curious, lets say if my compressor is rated at 6kW, and i only turn on air con for 1 room (9k btu/ 2.6kW), the energy consumption from the wall would it be 6kW or 2.6kW or slightly higher than 2.6kW?
 

wacko

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just curious, lets say if my compressor is rated at 6kW, and i only turn on air con for 1 room (9k btu/ 2.6kW), the energy consumption from the wall would it be 6kW or 2.6kW or slightly higher than 2.6kW?
don't confuse cooling capacity vs power consumption rate. in any case, the power consumption will be in line with what is being switched on, a compressor doesn't draw max power consumption all the time.
 

GBC

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just curious, lets say if my compressor is rated at 6kW, and i only turn on air con for 1 room (9k btu/ 2.6kW), the energy consumption from the wall would it be 6kW or 2.6kW or slightly higher than 2.6kW?
Using a MXY-3G28VA2 running MSXYFN10VE for 1 room, the total power input (normal rating) is around 0.62kw. The total energy consumption (simplified computation) would be 0.62kw x the operating hours of the compressor. Where I get the 0.62kw, please refer to the official starmex brochure.
 

shadow84

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wah jia lat... got nothing covering it, means I need even a bigger aircon for living room
Consider doing up a sliding glass door for the kitchen instead? Walkway area dun look so big, try calculate the total floor area of walkway + living room then convert to BTU and see if still within limits of the FCU.
 
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Consider doing up a sliding glass door for the kitchen instead? Walkway area dun look so big, try calculate the total floor area of walkway + living room then convert to BTU and see if still within limits of the FCU.
Probably will consider that but my kitchen is a square shape and the entrance is right from the corner of the square. So need to think about how to put a door with that layout.

Normally which formula do you guys use to calculate BTU needed? The Singapore website I used likely overestimate by quite a bit.
 

shadow84

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Probably will consider that but my kitchen is a square shape and the entrance is right from the corner of the square. So need to think about how to put a door with that layout.

Normally which formula do you guys use to calculate BTU needed? The Singapore website I used likely overestimate by quite a bit.
Typical calculation is area in m^2 / 5 x 3412 to get to BTU?
 

GBC

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Probably will consider that but my kitchen is a square shape and the entrance is right from the corner of the square. So need to think about how to put a door with that layout.

Normally which formula do you guys use to calculate BTU needed? The Singapore website I used likely overestimate by quite a bit.
 
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Typical calculation is area in m^2 / 5 x 3412 to get to BTU?
Both give very different value.

Area = 27 sqm
HDB Height = 2.6m
No. of people = 3

Shadow84: 18k BTU/hr
GBC: 10k BTU/hr

Which one should I use?
 

petetherock

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Both give very different value.

Area = 27 sqm
HDB Height = 2.6m
No. of people = 3

Shadow84: 18k BTU/hr
GBC: 10k BTU/hr

Which one should I use?
Get the bigger one and you'll never have to wonder if you should have..
The difference in cost isn't going to be that great.
 

pandemonium147

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Hi gurus,

I just came across this and would like to seek advise from all the experts here.

I am looking a Daikin ismile eco series for my new 5 room BTO (haven't received the key yet).
Below are the room dimensions, calculated BTU using the calculator (poor / very sunny / hot settings) & quoted aircon

1) Compressor -> MKM85VVGM (25.2K BTU)
Note: MKM100VVGM (29.4K BTU) is not considered as it might not fit through HDB window. Is this true?
2) MB (5000 x 3100 = 15.5 sqm) at 8,188 cal. BTU -> CTKM35VVMG (12K BTU)
3) Room #1 (3900 x 2900 = 11.31 sqm) at 7,045 cal. BTU -> CTKM25VVMG (9K BTU)
4) Room #2 (3900 x 2900 = 11.31 sqm) at 7,045 cal. BTU -> CTKM25VVMG (9K BTU)
5) Living & Dinning Room (5775 x 5625 + 3900 x 2825 = 43.5 sqm) at 16,825 cal. BTU -> CTKM71VVMG (24K BTU)

At night, if aircons in all three rooms are turned on, indoor BTU is 30K BTU which is higher than MKM85VVGM and MKM100VVGM can support. So the rooms will take longer time to cool and it will be not good for compressor in long run (true?).

At day, I guess aircons in the living room and 2 bedrooms at max will be turned on.
This will mean indoor BTU ranges from 42K to 45K BTU, which is significant higher than the outdoor BTU.

Based on the Daikin eco series brochure and the jexaircon link provided on the last post in pg. 332 earlier (unable to post link, sorry), MKM85VVGM is designed to support up to 4 rooms at 36.2K BTU (when running at max capacity).

I understand the concept of sum of indoor BTU must be equal or higher than outdoor BTU and compressor being under-capacity isn't good in the long run, based on what I read in this thread.

Can you advise me if the proposed aircon system is good enough, just need to manage when and which aircons to turn on?
Or should I look at alternative combinations, example like below?
Will installing 2 systems be overkill?
  • 1 system: 1x MKM100VVGM (29.4K BTU) + 2x CTKM25VVMG (9K BTU) + 1x CTKM35VVMG (12K BTU), if compressor can fit through HDB window
  • 2 systems: 1x MKM85VVGM (25.2K BTU) + 1x CTKM71VVMG (24K BTU) & 1x MKM85VVGM (25.2K BTU) + 2x CTKM25VVMG (9K BTU) + 1x CTKM35VVMG (12K BTU)
  • 2 systems: 1x MKM85VVGM (25.2K BTU) + 1x CTKM71VVMG (24K BTU) & 1x MKM75VVGM (20.5K BTU) + 3x CTKM25VVMG (9K BTU)
Thanks in advance!

Han
 

Jacqueline.

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spilt to 3 unit , not 1 unit.

If turn on all 3 together... than underpower liao

what do you think of this 3+1 aircon system? still underpowered?
  1. 24K for living room (38 square meter)
  2. 10K x3 for all bedrooms (12 square meter for CBR, 16 square meter for MBR)

Mitsubishi Starmex inverter sys.3 + sys.1
Model: MXY3GH28VA2/10/10/10VG (5 ticks)
Model: MUYGP/MSYGP24VF (3 ticks)
Total: $4968.
 

GBC

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Hi gurus,

I just came across this and would like to seek advise from all the experts here.

I am looking a Daikin ismile eco series for my new 5 room BTO (haven't received the key yet).
Below are the room dimensions, calculated BTU using the calculator (poor / very sunny / hot settings) & quoted aircon

1) Compressor -> MKM85VVGM (25.2K BTU)
Note: MKM100VVGM (29.4K BTU) is not considered as it might not fit through HDB window. Is this true?
2) MB (5000 x 3100 = 15.5 sqm) at 8,188 cal. BTU -> CTKM35VVMG (12K BTU)
3) Room #1 (3900 x 2900 = 11.31 sqm) at 7,045 cal. BTU -> CTKM25VVMG (9K BTU)
4) Room #2 (3900 x 2900 = 11.31 sqm) at 7,045 cal. BTU -> CTKM25VVMG (9K BTU)
5) Living & Dinning Room (5775 x 5625 + 3900 x 2825 = 43.5 sqm) at 16,825 cal. BTU -> CTKM71VVMG (24K BTU)

At night, if aircons in all three rooms are turned on, indoor BTU is 30K BTU which is higher than MKM85VVGM and MKM100VVGM can support. So the rooms will take longer time to cool and it will be not good for compressor in long run (true?).

At day, I guess aircons in the living room and 2 bedrooms at max will be turned on.
This will mean indoor BTU ranges from 42K to 45K BTU, which is significant higher than the outdoor BTU.

Based on the Daikin eco series brochure and the jexaircon link provided on the last post in pg. 332 earlier (unable to post link, sorry), MKM85VVGM is designed to support up to 4 rooms at 36.2K BTU (when running at max capacity).

I understand the concept of sum of indoor BTU must be equal or higher than outdoor BTU and compressor being under-capacity isn't good in the long run, based on what I read in this thread.

Can you advise me if the proposed aircon system is good enough, just need to manage when and which aircons to turn on?
Or should I look at alternative combinations, example like below?
Will installing 2 systems be overkill?
  • 1 system: 1x MKM100VVGM (29.4K BTU) + 2x MKM85VVGM (25.2K BTU) + 1x CTKM35VVMG (12K BTU), if compressor can fit through HDB window
  • 2 systems: 1x MKM85VVGM (25.2K BTU) + 1x CTKM71VVMG (24K BTU) & 1x MKM85VVGM (25.2K BTU) + 2x CTKM25VVMG (9K BTU) + 1x MKM85VVGM (25.2K BTU) (12K BTU)
  • 2 systems: 1x MKM85VVGM (25.2K BTU) + 1x CTKM71VVMG (24K BTU) & 1x MKM75VVGM (20.5K BTU) + 3x CTKM25VVMG (9K BTU)
Thanks in advance!

Han
If your BTU computations are correct, I think the best combination would be 2 separate systems :-

1 x MKM85VVGM (25.2K BTU) for your 3 bedrooms ie 1 x CTKM35VVMG (12K BTU) + 2 x CTKM25VVMG (9K BTU). Reason being that with the MKM85VVGM, your CTKM35VVMG will be limited to 9,826 BTU and your 2 x CTKM25VVMG will be running at 7,029 BTU each which fit in nicely with your BTU requirement for each bedroom.
1 x RKS71LVMG / FTKS71LVMG (24,200 btu) single split system for living & dinning room.
 

pandemonium147

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If your BTU computations are correct, I think the best combination would be 2 separate systems :-

1 x MKM85VVGM (25.2K BTU) for your 3 bedrooms ie 1 x CTKM35VVMG (12K BTU) + 2 x CTKM25VVMG (9K BTU). Reason being that with the MKM85VVGM, your CTKM35VVMG will be limited to 9,826 BTU and your 2 x CTKM25VVMG will be running at 7,029 BTU each which fit in nicely with your BTU requirement for each bedroom.
1 x RKS71LVMG / FTKS71LVMG (24,200 btu) single split system for living & dinning room.

The BTU computations are based on the BTU calculator given here.
How do you calculate the limiting BTU? is it by percentage?
 

GBC

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The BTU computations are based on the BTU calculator given here.
How do you calculate the limiting BTU? is it by percentage?
It's stated in the official Daikin brochure.. look at page 29
 

harky

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what do you think of this 3+1 aircon system? still underpowered?
  1. 24K for living room (38 square meter)
  2. 10K x3 for all bedrooms (12 square meter for CBR, 16 square meter for MBR)

Mitsubishi Starmex inverter sys.3 + sys.1
Model: MXY3GH28VA2/10/10/10VG (5 ticks)
Model: MUYGP/MSYGP24VF (3 ticks)
Total: $4968.

living room (38 square meter) = 15,925 BTU
1 bed room = 12sq metre so is 7,233 BTU /rm
2 bed room = 16sq metre so is 8,924 BTU /rm


Let say u get:

Room X 3
MXY-3G28VA2 (Outdoor unit) is 6kw = 20472.852 BTU <-- this cannot support 3 room turn on aircon together le.
MSXY-FN10VE (indoor unit) is (2.8kw = BTU 9553.9976) X 3 = 28,661.9928 BTU

Living Rom (if u want cold living room better up ur outdoor unit, but i dont think living rm will be cold lo. use ceiling fan le)
MXY-2G20VA2 (Outdoor unit) is 4.5kw = 15354.639
MSXY-FN18VE (indoor unit) is (5.0kw = BTU 17060.71)

or get
MXY-4G38VA2 (Outdoor unit) is 7.4kw = 25249.8508 BTU <-- turn on 3 room AC will spit into 8,416.61 BTU /rm
MSXY-FN10VE (indoor unit) X 3
MSXY-FN18VE (indoor unit) X 1

or
MXY-5G48VA2 (Outdoor unit) is 9.2kw = 31391.7064 (can max use MSXY-FN10VE indoor unit for room)

no issue to support 3 room or living rm as long u dont turn all 4 air con together.. either 3 or 1 turn on :)


google but cant find MUYGP/MSYGP24VF..............


use this AC BTU Calculator for room, setting all set to the lowest one

use this to convert kw = btu
 
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