Air conditioning - Any recommendations please??

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shadowoflight

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Mitsubishi 3A38VA - this was old 4 ticks, new 2 tick rated?

Coz if this is the case, then it seems like gain city is still selling them as 4 ticks.
 

Otherp

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Mitsubishi 3A38VA - this was old 4 ticks, new 2 tick rated?

Coz if this is the case, then it seems like gain city is still selling them as 4 ticks.

I'm no expert, but I think the product itself has remained the same. The energy efficiency measurement and "tick" system changed in 2015 resulting in a re-classification of many of the air conditioners. Perhaps the stickers you saw at Gain City are the older stickers.
 

terumo

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To Otherp,

Agreed, product is still the same.
Its the NEA Rating system that has changed.
 

thecat21

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To thecat21,

That will depends on your usage.

max usage both bedrooms 8hr/day + living room will use rarely only.
Any recommendation will be appreciated.
Or if you can point me in the right direction to read up :D
Tried googling but sometimes specs do not list BTU etc.
 

dachee

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hihi he say with my usage if use 5 ticks he will have to come back again and again as I'm sure to complain :p

is it true that for my requirement of 18k living, 12k BR1, 9k BR2 if i use 5 tick compressor, it will not have power to support? Will a 2 tick be better in this sense?

Living room aircon is used 7pm to 12am wkdays, more hours on wkends.
and we are likely to also use on 1 of the BRs.

Courts salesman told me 5 Tick compressor for sys 3 can only support 2x9k btu efficiently. for my requirement he also recommend 2 ticks. and 2 ticks is previous 4 ticks. I shall consider more on my usage than the ticks.

Gain city sales man said 5 tick compressor can support my living 18k, BR1 18k(he recommend 18k instead of 12k) and BR2 9k, can on 2 at the same time.

The more i hear, the more confused i am :s13:

Hi,

Ok, but did he say what you will likely to complain about? Like what type of problems? For example: not cool, leaking, unit not working. What I am trying to find out is whether the problems that he is referring to is product problem or installation problem. Though he did said that the 2 ticks model will be ok, I think he is referring to the product. But again what are the problems? Knowing the problems will allow us to make the appropriate decision. Sweeping comment like the one made by the salesperson is not helpful or creditable.

The number of ticks has nothing to do with having sufficient power or not to support your FCUs configuration (combination). The ticks refer to the relationship between input power against the capacity of cooling used.

So a 5 ticks has a better efficiency than a 2 ticks.

Looking at the Mitsubishi 2 ticks configuration, you will realized that for all the systems, none of the condenser is able to support full capacity of the FCUs in its configuration. But full capacity is affected by the temperature setting, meaning the amount of heat that needs to be removed and not the hours of usage.

You therefore need to know what temperature that you would like your room to be. Is 25 degree ok? will you ever use 18 degree? How fast would you like your room to be cooled down to the temperature you set? Note that cooling down is dependent on temperature and fan speed as well as indoor temperature and outdoor temperature. Is the difference in cooling down time a critical factor for you? The hours of operation only affect your operating cost, so the longer you use your system, the more you need to pay. However, you will pay lesser for the 5 ticks than the 2 ticks for the same period and temperature setting used due to its higher COP.

Off course, if you use higher condenser capacity, then its support to the individual FCU can be better and closer to its full capacity but still not at full capacity because (if I am not wrong), the manufacturer does not expect people to size the FCU to its max capacity. Ie, if you really need a 9k Btu/hr all the time, then you would likely size it one step higher. But over sizing is not good.

The system 3 capacity according to the spec is up to 6 kW/h at normal rating. The MSXY-FJ10VE, if not wrong is a 2.5kW/h capacity FCU, so 2X2.5 = 5 kW/h which is lesser than the MXY-3G28VA normal rating of 6 kW/h. But if you add another FJ10VE, your full capacity becomes 3X2.5 = 7.5KW/h. In such a case, with 3 FJ10VE, you will not be able to reach a total of 7.5 kW/h because the condenser can only give 6 kW. But if you read the rating for the condenser, there is a range of 6 (2.9 - 8.9), meaning that there is a max rating of up to 8.9 kW but this is only for a short while.

The question is what is your required temperature and how much Btu (heat) is required to be removed to reach each room?

For example: if you have a room of L4XW3XH2.8 m with normal heat insulation and the room temperature is 32 degree C and you want to bring it down to 20 degree C, then according to the Btu calculator at: http://www.calculator.net/btu-calcu...=12&temperatureunit=c&calctype=heat&x=58&y=14

you will need 4.761k Btu or 1.395 kW. So having 3 FCU in such a room size and heat reduction, you only need 1.395X3 = 4.185 kW which is within the 6 kW available in the system 3.

So do your calculation rather than assuming your Btu/h usage. Sometime instead of one FCU you may need 2 FCUs within a large area for more efficient heat removal.

The above are my opinion and hope they are helpful.
 
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dachee

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Im getting a 4 bedroom, breaking 1 bedroom to extend living room. (although the kitchen is also open concept)

As such, from data gathered here i've deduced that I need an 18k for living room and 9k each for the other 2 bedroom ? Is 18k enough for the extended living room + open kitchen ?

Considering the mitsubishi option above @ $3461 , is this the price i must pay for this setup ? or do I have to pay more for a 18k BTU unit, trying to make sense of how this works, if anyone can recommend a good setup for me, will be a great help !

Hi,

May I know how you arrives with the 18k Btu/h for your living room and 9k Btu/h for your bedroom? Not to test you but just for counter check that you are on the right track.

According to the website selling it at $3461, it was mentioned that it is inclusive of installation for HDB and for all 9k FCUs. If you up size your FCU, there will be extra cost. But again, it is good to size your system correctly prior to order. Is 18k Btu sufficient?

Operating the air conditioner would incur cost to remove the heat from the space so that the air surrounding us make us feel comfortable. Ideally, if this air surrounding us can be make to follow us where ever we move within the room, then this surrounding air need only be a thin layer around us instead of having this air filling the room fully. Unfortunately this does not happen and we need to pay for the cost of filling the whole room with this comfort air.

As the size of this comfort air is increased so would your operating cost. It would be wise to make the room that this comfort air need to fill as small as possible / feasible.

There are other factors that will also affect the comfort air and this include other heat sources like stove, oven, all kitchen cooking appliances, motors devices like your fridge, water source which affect the humidity in the room and consume energy to remove the water as well as draining off the coolness within the room and heat from outside like a frequently opened door, non-shaded windows or poorly shaded windows and non-insulated sun facing walls and other appliances like water heater, dish washer, etc.

Ask yourself whether you would like to CONTINUOUSLY paying to cool all this heat generated that are CREATED HEAT rather than the heat coming from your body and those that you cannot controlled?

In short, it may not cost much to remove all this CREATED HEAT by some form of barrier at a one time payment (cost) and pay lesser very time you use the air conditioner or to pay more for every use. The choice is yours.

The above are my opinion and hope that they are useful.
 
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ironut

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Dachee, my roo. Humidity can sometimes drop below 45 after aircon is on for some time. Too dry.

Any tips on how we can maintain the humidity at a comfortable level, yet still cool? E.g. at 50 to 55

Sent from GAGT using GAGT
 

dachee

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So 24k + 9k + 9k system 3 ? How many compressors would I need ?

Hi,

Without looking at your floor plan and ceiling height as well as your activity and equipment in the room, it is difficult to calculate the Btu needed.

Hour of usage does not affect the Btu/h needed.
 
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dachee

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So 24k + 9k + 9k system 3 ? How many compressors would I need ?

Hi, after calculating the Btu/h needed for each room, we then decide on the number of FCUs required as well as the number of condensers which is dependent on the possibility of addition power points, outdoor space and cost. Look at the energy label which indicates the annual energy cost that you will be paying when used in a "typical way", according to NEA's assumption. The 2 ticks and 4 or 5 ticks could mean that you ended up paying more than $600/year. So choose wisely.

Sometime, instead of one 18k Btu/h FCU, it may be more efficient and effective to have two FCUs at the appropriate location.

The above are my opinion and hope that they are helpful.
 
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shadowoflight

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I'm pretty much set on mitsubishi's 5 tick system 3, with the MXY-3G28VA.

I'd like to hear what you guys think about Daikin's MKS-65QVMG though.
 
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