Air conditioning - Any recommendations please?? - Part 2

Alibeckham

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Hellos all the shifus here.. looking for new aircon for my resale EA.. following are my estimated room size
Main Bedroom - 18.5sqm
Bedroom 2 - 15sqm
Bedroom 3 - 12.5sqm
Living + dining - 57sqm

I am thinking whether this configuration works or not?

mitsubishi Starmex - MXY-4G33VA2 = Msxy-FN24VE + FN13VE + 2 x FN10VE

wonder if this configuration is ok or under size? And any rough estimate what is a good price for all in cost, including best insulation and coil material?
 

Alphas

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Hellos all the shifus here.. looking for new aircon for my resale EA.. following are my estimated room size
Main Bedroom - 18.5sqm
Bedroom 2 - 15sqm
Bedroom 3 - 12.5sqm
Living + dining - 57sqm

I am thinking whether this configuration works or not?

mitsubishi Starmex - MXY-4G33VA2 = Msxy-FN24VE + FN13VE + 2 x FN10VE

wonder if this configuration is ok or under size? And any rough estimate what is a good price for all in cost, including best insulation and coil material?
Really, the room sizes are large, I suggest you get at least 2 compressors 2x MXY-4G38VA2. One compressor for the 3 bedroom FCU (FN13VE + 2 x FN10VE) and the second compressor for the living/dining (2x FN18VE).
 

Alibeckham

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Really, the room sizes are large, I suggest you get at least 2 compressors 2x MXY-4G38VA2. One compressor for the 3 bedroom FCU (FN13VE + 2 x FN10VE) and the second compressor for the living/dining (2x FN18VE).
Hi hi, yup the rooms seems slightly bigger than bto. For the living room one, I seldom on and will not on concurrently with the room, that’s why only looking at 1 compressor configuration.

I got a quote from supplier and recommended with
Mitsubishi Starmex inverter sys.4 MXY4G33VA2/10/10/13/24VE @ $4200

With standard installation - 0.5“ insulotion, sigma cable, S22 pipe and 16” drain

would like some sensing if this compressor model is able to support the scenario (a) 10/10/13 on together (b) some days just on 24ve?

understand this model capable of 36.5 btu?
 

Alphas

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Hi hi, yup the rooms seems slightly bigger than bto. For the living room one, I seldom on and will not on concurrently with the room, that’s why only looking at 1 compressor configuration.

I got a quote from supplier and recommended with
Mitsubishi Starmex inverter sys.4 MXY4G33VA2/10/10/13/24VE @ $4200

With standard installation - 0.5“ insulotion, sigma cable, S22 pipe and 16” drain

would like some sensing if this compressor model is able to support the scenario (a) 10/10/13 on together (b) some days just on 24ve?

understand this model capable of 36.5 btu?

MXY4G33VA2 is only rated at 6.6KW (22.5K BTU), it will be grossly under powered in your configuration with such large rooms. 36.5K BTU is taking into account the max capacity which cannot be sustained for long duration. If you only want to get one compressor, then at least a MXY-4G38VA2 or MXY-4G48VA2 if the constraints permits. The standard insulations looks alright, thickness of the insulation on copper pipes of 1/2" and include 1/4" insulation for the drainage pipes.
 

Alibeckham

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Tot the Mitsubishi brochure say the condenser rating is


Multi split outdoor unit for up to 4 indoor unit

Total capacity of all indoor unit must not exceed 20.5kw”
 

GBC

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Tot the Mitsubishi brochure say the condenser rating is


Multi split outdoor unit for up to 4 indoor unit

Total capacity of all indoor unit must not exceed 20.5kw”
20.5kw = 69,948 BTU. If your outdoor unit MXY4G33VA2 is only rated at 6.6KW (22.5K BTU), how can 6.6 kw support your 4 indoor units to exceed 20.5kw ?
 

Alibeckham

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20.5kw = 69,948 BTU. If your outdoor unit MXY4G33VA2 is only rated at 6.6KW (22.5K BTU), how can 6.6 kw support your 4 indoor units to exceed 20.5kw ?

Sorry for my noob question, then how come so many retailers and aircon supplier selling 33VA2 model coupled with the 24VE?

See courts >> https://www.courts.com.sg/mitsubish...fn24ve-inverter-sys-4-aircon-install-ip133616


So confusing now..
 

wacko

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So that it's easier to make a quick upsell later on.
 

petetherock

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I see a lot of users trying to cut on their compressors, I wonder if anyone regretted it ?
I went in the other direction and oversized mine
No regrets
 

jaefan

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Just got my new Daikin iSmile Eco System 2 installed by 2 guys from Gain City today. Purchased on 27th August, was offered to install on 6th Sept but I asked for 8th Sept when I am working from home today.

They are SO much better than our previous experience from Courts who got third party contractors to install our Panasonic inverters 6-7 years ago... He immediately saw that the piping was not done at an angle which caused one of our fancoil to condense and have icing formed inside rather quickly. Literally spent loads of money to just do chemical overhaul (every year) or topping up every time the servicing guys come (I call for servicing every 4 to 5 months). Just topped up twice within this year, some more last was in July. But the Airecontrol servicing lads were already telling us to get ready for the Panasonic a/cs to pass on soon.

Even though GC is not super cheap plus I chose to upgrade the piping and etc, I feel that they are more professional. Kept asking them questions but uncle was kind enough to answer even though he's like "you mean you don't know this too???" towards the end, lol.

All in all, I hope this time the ac lasts longer than 7-8 years with regular cleaning... he say we can just wash off the dust from the filters every month ourselves then no need to call for servicing that often.
 

GBC

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Sorry for my noob question, then how come so many retailers and aircon supplier selling 33VA2 model coupled with the 24VE?

See courts >> https://www.courts.com.sg/mitsubish...fn24ve-inverter-sys-4-aircon-install-ip133616


So confusing now..
The job of a aircon salesman is to sell you an aircon system. He will earn his commission as long as he sells you a system regardless of whether it's an underpower, adequately powered or even overpowered aircon system. It's also easier to sell a cheaper underpowered than a more expensive adequately powered system. There's also a lot of combinations of indoor units + outdoor unit so basically its up to the customer to decides what he wants to get based on his budget.

So if you are going to spend a few thousand dollars buying a new aircon system, you should at least take the trouble to read and understand the aircon brochures rather than just depend on what the aircon salesman say.
 

Rayleigh1

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Started having issues with my aircon system recently. It's an older gen Mitsubishi Starmex that I've been using for quite a number of years. Initially, the aircon would stop by itself after awhile and there would be a continuous blinking light. According to the troubleshooting manual, it seems to be an issue with the circuit board and more specifically the outdoor unit circuit board since all the indoor units go down at the same time. I've been able to get the aircon running again by switching the power mains off and on, although it can take several tries sometimes. Now, even when the aircon comes alive again, it's just not cold at all although I can still feel the air flow from the indoor unit.

Anyone knows if there is loss of refrigerant due to an actual leakage (that warrants equipment/plumbing replacement), would the pressure reading go down to almost zero/zero?

Also, anyone knows whether the lack of refrigerant can somehow trigger this: aircon would stop by itself after awhile and there would be a continuous blinking light? Or is the inbuilt troubleshooting diagnosis almost always spot on?

Thanks in advance for any advice
 
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LiLAsN

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Started having issues with my aircon system recently. It's an older gen Mitsubishi Starmex that I've been using for quite a number of years. Initially, the aircon would stop by itself after awhile and there would be a continuous blinking light. According to the troubleshooting manual, it seems to be an issue with the circuit board and more specifically the outdoor unit circuit board since all the indoor units go down at the same time. I've been able to get the aircon running again by switching the power mains off and on, although it can take several tries sometimes. Now, even when the aircon comes alive again, it's just not cold at all although I can still feel the air flow from the indoor unit.

Anyone knows if there is loss of refrigerant due to an actual leakage (that warrants equipment/plumbing replacement), would the pressure reading go down to almost zero/zero?

Also, anyone knows whether the lack of refrigerant can somehow trigger this: aircon would stop by itself after awhile and there would be a continuous blinking light? Or is the inbuilt troubleshooting diagnosis almost always spot on?

Thanks in advance for any advice
If there is a leakage in your home, you have a chance of breathing in the toxic gas and/or risk a fire if there's a spark in your room due to the flammable aspect of the gas. Don't take any chances and fix the issue asap. Make sure that they find the leak and change out the piping completely. Unacceptable to have a leak in a closed loop system where you never have to top up the gas. Ever.
 

Rayleigh1

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If there is a leakage in your home, you have a chance of breathing in the toxic gas and/or risk a fire if there's a spark in your room due to the flammable aspect of the gas. Don't take any chances and fix the issue asap. Make sure that they find the leak and change out the piping completely. Unacceptable to have a leak in a closed loop system where you never have to top up the gas. Ever.
No loss of refrigerant even after 10+ years of usage? I thought there would always be gradual loss since it's impossible for the aircon system to be air tight. There would still be a gradual leak which is almost negligible in the short term but over 10+ years of usage, it would add up to something right?
 

batniss

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No loss of refrigerant even after 10+ years of usage? I thought there would always be gradual loss since it's impossible for the aircon system to be air tight. There would still be a gradual leak which is almost negligible in the short term but over 10+ years of usage, it would add up to something right?
no loss.

i have never top up before and my aircon still work at tip-top condition..
 

batniss

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Someone checked your gas when they came down for servicing?
i did my own service. Gas i don't know how to do so if my own service my aircon still cmi, I will be forced to call them. But if I have never called them.. tells a lot
 

Rayleigh1

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i did my own service. Gas i don't know how to do so if my own service my aircon still cmi, I will be forced to call them. But if I have never called them.. tells a lot
Oh.. So it's more of a everything working normally = no leak. Thanks for sharing.
 

batniss

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Oh.. So it's more of a everything working normally = no leak. Thanks for sharing.
that's what matters most right? Do you buy the aircon for other purposes as well? To sing and dance for you?
 

LiLAsN

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No loss of refrigerant even after 10+ years of usage? I thought there would always be gradual loss since it's impossible for the aircon system to be air tight. There would still be a gradual leak which is almost negligible in the short term but over 10+ years of usage, it would add up to something right?
Yes. No leaks should happen. Similar to how we never ever top up our refrigerators which also use the same technology as airconditioners. Those too can last for years and years provided there's no other problems occurring to make the unit fail sooner.

Similar to how your Desktop PCs CPU coolers are too. Remember the term Xbox uses, Vapor Chamber? In that metallic block of heatsink that looks similar to our heatsink on our aircon, there is a gas too that helps to carry the heat away from the CPU area up the middle copper piping to help disperse the heat from the CPU to the metal fins. You don't even have to replace those metal heatsinks at all. Maybe just replace the fan if it ever dies. Because again, it's a closed loop.

I've read in a longer post earlier in this thread about how these are some of the tactics that some underhanded aircon technicians do to ensure that in the future, you will need to use their services again for aircon servicing. And then they charge you for 'gas top-up' that should never ever be part of any servicing as that indicates you have a leak and they are purposely ignoring that leak so that you will come back to them again to 'top it up' again. Please be careful.

That is why I recommend those using water pressure to wash your aircon fins as opposed to dismantling your unit to clean them as they might do unscrupulous things such as purposely not assembling it back properly and letting the gas leak later on. So I do not at all recommend chemical wash where they will have to dismantle your unit.
 
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