Sizing For Home Aircon

[dreamhouse 0]

what should be the power for my home aircon?

inter terrace, 3 bedrooms, 3x6m, 3x8m and 4x6m

not heavy user, only switch on at night if weather is too hot, cannot sleep

don't want to over-size the aircon requirement

thanks

[simhup 0]

what should be the power for my home aircon?

inter terrace, 3 bedrooms, 3x6m (min. 9000 BTU), 3x8m (min. 12000BTU) and 4x6m (min. 12000BTU)

not heavy user, only switch on at night if weather is too hot, cannot sleep

don't want to over-size the aircon requirement

thanks

[neubie 2]

often its better to slightly oversize the cooling capacity, as the moment the optimum temperature is reached faster, the compressor will run at the minimal current just to maintain the set temperature.

if u just gum gum dimension the required cooling capacity, you might find that under operation, your compressor is not really running at a the lowest possible current.

[dreamhouse 0]

often its better to slightly oversize the cooling capacity, as the moment the optimum temperature is reached faster, the compressor will run at the minimal current just to maintain the set temperature.

if u just gum gum dimension the required cooling capacity, you might find that under operation, your compressor is not really running at a the lowest possible current.

a contractor recommended 1x12000 BTU + 2x12000 BTU (split unit) panasonic aircon

so there will be 2 compressors...

for the split unit ones - does it mean that if i switch on both at the same time, the rooms will need longer time to cool down? or will it take forever?

[alvinloo 0]

To have 2 compressors with 3 fancoils doesn't seem cheap. Usually the compressor is more costly.

I would suggest you go get a conventional system-3 aircon that supports 3 fancoils.

The overall "strength" of your aircon system is determined by the outdoor compressor unit. If that unit supports up to 36,000BTU/hr (about 4 horsepower), and if all 3 rooms turn on their 12,000BTU/hr fancoils, no problem. Your outdoor compressor unit will just be running at it's full capacity.

However, if you get a 30,000BTU/hr (about 3 horsepower) outdoor compressor unit, if 2x 12,000BTU/hr fancoils are already running, turning on the 3rd fancoil will cost your compressor to overwork and will depend on the characteristic of the system-3 aircon, probably 3x rooms will be running at 10,000BTU/hr each, or 2x rooms at 12,000BTU/hr each, last room only be running at 6,000BTU/hr, etc.

I agree with simhup, probably a 9,000BTU/hr and 2x 12,000BTU/hr fancoils should be sufficient, assuming your room is about 2.5m-2.7m in height. If you have a huge built-in/walk-in wardrobe or a high ceiling, those factors would need to be taken into consideration as well.

And get those with R410A as the aircon refrigerant, rather than the older R22 refrigerant.

Just go into any aircon shops and have a chat with the salesperson, they should be able to share more with you.