Air conditioning - Any recommendations please?? - Part 2

[The_King]

My toilet always have some form of condensation. Is it better to get armaflex shield cx1/2 inch or class 0 3/4 inch?

3/4 as it thicker but insulation cannot squeeze, if no space then 1/2

 

[8-lane]

Hooted a Panasonic X-inverter system 1 at $343 with replacement service from S Z Aircon Pte Ltd on Shopee after deduction of $400 climate voucher... hope all goes well...

 

[The_King]

Hooted a Panasonic X-inverter system 1 at $343 with replacement service from S Z Aircon Pte Ltd on Shopee after deduction of $400 climate voucher... hope all goes well...

Wtf so cheap

 

[The_King]

thinking back, until your post, i think my 2nd ac on my new home will be

SWG 20
drainage pipe 25mm
insulation 1inch

get a good company with good rep (maybe newway, maybe amyth, maybe coolserve) then when AC GG, just do a aircon replacement (when old one GG) which i saw on ecom only 500 to 850 for NEW AC replacement (use back everything else)



since i only need to cool down 1 room, all i need is a system 1, as such replacement is better then repair in my case



nv knew i could do this, but not too late since my 2nd ac not up yet, but for my 1st ac too late liao

 

[shaojie2k]

I m planning to buy this system 4 3x12kbtu 1x24kbtu to replace the Panasonic one for my re-sale EA. hope to have u guys inputs and advice what I should look out for especially those with experience with this model or manufacturer.

the contractor offers the following materials for the piping and trunking
16mm pvc drainage
class 0 armaflex 3/8 n 5/8 thickness insulation for 21swg copper pipe (made in Thailand/Malaysia)
4 core wires 4c40 & 3c70 (made in singapore)

https://coolserve.com/wp-content/up...i-Heavy-Industries-Rocket-series-2025-NEW.pdf

 

[The_King]

I m planning to buy this system 4 3x12kbtu 1x24kbtu to replace the Panasonic one for my re-sale EA. hope to have u guys inputs and advice what I should look out for especially those with experience with this model or manufacturer.

the contractor offers the following materials for the piping and trunking
16mm pvc drainage
class 0 armaflex 3/8 n 5/8 thickness insulation for 21swg copper pipe (made in Thailand/Malaysia)
4 core wires 4c40 & 3c70 (made in singapore)

https://coolserve.com/wp-content/up...i-Heavy-Industries-Rocket-series-2025-NEW.pdf

you nv say which model but based on the pdf i guessing scm40ys or 27k btu

since you only got 27k btu, you have to know which room need to on ac as you cant on them all at the same time


there a few idea here.

• some prefer to have more btu then needed so it AC last much longer

• some prefer just right (right type of btu, right temp 24c to 27c) and dont feel the need to have lot of btu as once set temp is reach, the extra btu is not needed

• some view and plan ac as in planned obsolescence cause feel thing are not as lasting as last time, mean focus is $$$$

 

[shaojie2k]

you nv say which model but based on the pdf i guessing scm40ys or 27k btu

since you only got 27k btu, you have to know which room need to on ac as you cant on them all at the same time


there a few idea here.

• some prefer to have more btu then needed so it AC last much longer

• some prefer just right (right type of btu, right temp 24c to 27c) and dont feel the need to have lot of btu as once set temp is reach, the extra btu is not needed

• some view and plan ac as in planned obsolescence cause feel thing are not as lasting as last time, mean focus is $$$$

thanks for ur insights! yea, I actually prefer spending more now for a system that is more lasting. but this model if I m not wrong just debut in jul so am relying on brand name for confidence

yes it is the scm40ys-w, 3xSRK13YYS + 1XSRK24YYS, they claim free upgrade from 9btu to 12btu for all fcus so I just took it up. 24btu one is for the living room with top up of $150

I compared it to the equivalent starmex n daikin seems to be about the same in terms of cooling performance and functions wise. am also drawn to the better looking fcus n wifi control...aghh so many things to consider. guess I'm getting u guys insights to correct my sense of priority haha

 

[The_King]

thanks for ur insights! yea, I actually prefer spending more now for a system that is more lasting. but this model if I m not wrong just debut in jul so am relying on brand name for confidence

yes it is the scm40ys-w, 3xSRK13YYS + 1XSRK24YYS, they claim free upgrade from 9btu to 12btu for all fcus so I just took it up. 24btu one is for the living room with top up of $150

I compared it to the equivalent starmex n daikin seems to be about the same in terms of cooling performance and functions wise. am also drawn to the better looking fcus n wifi control...aghh so many things to consider. guess I'm getting u guys insights to correct my sense of priority haha

there no wrong or right. spoil or last long is heng or suay.
the question is if it spoil, are you going to repair or replace base on your choice


my company midea system 1 i think this yr 5 or 7yr liao. still working even when it hardly service

 

[Mecisteus]

Found a local supplier selling Tuya wifi module for Starmex. Daikin is also available. They are selling the Home Assistant version too.

I know you can fully DIY with esphome but I can't seem to find for Tuya. And I prefer to integrate into my Smartlife devices.

Shopee and Lazada are also selling. Supplier is very helpful. Just sharing.

https://spacemate.sg/tuya-wifi-module-installation-guide/

 

[shaojie2k]

there no wrong or right. spoil or last long is heng or suay.
the question is if it spoil, are you going to repair or replace base on your choice


my company midea system 1 i think this yr 5 or 7yr liao. still working even when it hardly service

yes that's y I top up for the extended warranty

I pull the figures to chatgpt to analyse n compare their performance, are they even accurate?

Your exact configurations:​

Mitsubishi Heavy SCM80YS (3 × SRK13YYS + 1 × SRK24YYS)​

• Bedrooms each receive 1.67 kW
• Master receives 3.03 kW
• Total: 8.0 kW (max 8.0)
• Min input: 0.4 kW
• Known for stable humidity removal & dry coil designs

Daikin MKM85ZVMG (CTKM25 + CTKM25 + CTKM25 + CTKM71)​

• Bedrooms each receive 1.27 kW
• Master receives 3.59 kW
• Total: 7.4 kW (max 10.24)
• Min input: 0.27 kW
• Known for lowest energy use and strong master-room performance

---

2. What REALLY matters for a Singapore home​

Most people overfocus on BTU.
The truth is: the delivered capacity per room + humidity control performance is what determines:

• comfort
• skin dryness
• mould growth
• electricity bills
• air quality
• night-time sleep quality

Below is the breakdown by real-life concerns.

---

3. Skin Sensitivity​

✔ Winner: Mitsubishi Heavy SCM80YS​

Why?​

1. Higher delivered capacity in bedrooms (1.67 vs 1.27 kW)
   • Faster pull-down → shorter periods of over-blowing cold air on skin
   • Less aggressive prolonged cooling needed
   • More balanced coil temperature → avoids over-drying
2. Better humidity extraction
   MHI systems typically run:
   • colder indoor coil
   • longer coil-contact time
   • more stable airflow
     This means lower dewpoint and reduced skin stickiness, but not excessive dryness.
3. Compressor stability
   SCM40YS uses a very conservative compressor ramp-up curve
   → avoids sudden blasts of super-cold dry air that irritate eczema.
4. Finer airflow control on SRK series
   • more gentle swing pattern
   • smoother fan transitions
     Excellent for people whose skin reacts to drafts.

4. Mould Prevention & Humidity Control​

✔ Overall Winner: Mitsubishi Heavy SCM80YS​

Because mould is a humidity problem, not a BTU problem.

Why MHI wins:​

(1) Stronger bedroom dehumidification​

Higher delivered cooling capacity =
faster humidity pull-down, especially in smaller rooms.

(2) More stable compressor speed​

Stable coil temperature =
more reliable dew formation on coil =
better moisture removal.

(3) SRK indoor units have:​

• large heat exchanger surface
• better refrigerant distribution
• slower fan minimum speed
  These are ideal for mould suppression.

(4) Daikin’s main weakness​

Daikin multi-systems are optimised for efficiency →
They often run warmer indoor coils to save energy.

This results in:
slower humidity removal
more “still damp” feeling
higher mould risk on walls, wardrobes, leather bags, mattresses

5. Overnight Bedroom-Only Use (Real Singapore Scenario)​

✔ Winner: Daikin for electricity​

✔ Winner: MHI for comfort, dryness, mould control​

If running only 1–2 bedrooms:

Daikin strength​

• lowest minimum compressor load (0.27 kW)
• lowest electricity draw
• excellent whole-night efficiency

Daikin weakness​

Because its minimum load is LOW, the system tends to:

• run the compressor warm
• reduce condensate formation
• humidity creeps back up after 2–3 hours
• airflow stays “dry but not dehumidified” → bad for eczema

MHI strength​

Even with higher min load (0.4 kW), MHI maintains:

• colder coils
• better condensation
• stable humidity at 70–75% RH down to 55–60% depending on setpoint
  This is the ideal RH range for skin comfort and mould prevention.

6. Cooling Performance by Room Type​

Bedrooms (small rooms)​

✔ MHI wins

• more cooling power in small volumes
• faster drop in humidity
• quicker achievement of steady, gentle airflow
• ideal for sleeping comfort

Master Room (largest room)​

✔ Daikin wins

• 3.59 kW delivered
• better for large open spaces
• better if master room west-facing, afternoon sun, or large windows

7. Air Cleanliness & Coil Hygiene​

Mitsubishi Heavy​

✔ Best coil cleanliness in real use

• hydrophilic coil surfaces
• stable coil temps → less condensation cycling → less slime
• more logical fan-dry mode

Daikin​

✔ Good filters
⚠ Coil tends to run warmer → condensation cycles can cause musty smell faster if maintenance is delayed.

---

8. Compressor & Reliability Considerations​

Mitsubishi Heavy​

✔ Overbuilt compressors
✔ Very stable current draw
✔ Minimal surges
✔ Runs cooler internally
→ long lifespan, especially in Singapore humidity
→ fewer PCB failures

Daikin​

✔ Excellent efficiency
⚠ Higher surge current (up to 14.5A)
⚠ More sensitive to distribution imbalance
⚠ Maintenance-sensitive to keep efficiency high

---

9. Electricity Cost​

With your usage (3 bedrooms regularly):​

• Daikin uses about 10–18% less electricity
• MHI provides better humidity and comfort at slightly higher cost

 

[The_King]

yes that's y I top up for the extended warranty

I pull the figures to chatgpt to analyse n compare their performance, are they even accurate?

Your exact configurations:​

Mitsubishi Heavy SCM80YS (3 × SRK13YYS + 1 × SRK24YYS)​

• Bedrooms each receive 1.67 kW
• Master receives 3.03 kW
• Total: 8.0 kW (max 8.0)
• Min input: 0.4 kW
• Known for stable humidity removal & dry coil designs

Daikin MKM85ZVMG (CTKM25 + CTKM25 + CTKM25 + CTKM71)​

• Bedrooms each receive 1.27 kW
• Master receives 3.59 kW
• Total: 7.4 kW (max 10.24)
• Min input: 0.27 kW
• Known for lowest energy use and strong master-room performance

---

2. What REALLY matters for a Singapore home​

Most people overfocus on BTU.
The truth is: the delivered capacity per room + humidity control performance is what determines:

• comfort
• skin dryness
• mould growth
• electricity bills
• air quality
• night-time sleep quality

Below is the breakdown by real-life concerns.

---

3. Skin Sensitivity​

✔ Winner: Mitsubishi Heavy SCM80YS​

Why?​

1. Higher delivered capacity in bedrooms (1.67 vs 1.27 kW)
   • Faster pull-down → shorter periods of over-blowing cold air on skin
   • Less aggressive prolonged cooling needed
   • More balanced coil temperature → avoids over-drying
2. Better humidity extraction
   MHI systems typically run:
   • colder indoor coil
   • longer coil-contact time
   • more stable airflow
     This means lower dewpoint and reduced skin stickiness, but not excessive dryness.
3. Compressor stability
   SCM40YS uses a very conservative compressor ramp-up curve
   → avoids sudden blasts of super-cold dry air that irritate eczema.
4. Finer airflow control on SRK series
   • more gentle swing pattern
   • smoother fan transitions
     Excellent for people whose skin reacts to drafts.

4. Mould Prevention & Humidity Control​

✔ Overall Winner: Mitsubishi Heavy SCM80YS​

Because mould is a humidity problem, not a BTU problem.

Why MHI wins:​

(1) Stronger bedroom dehumidification​

Higher delivered cooling capacity =
faster humidity pull-down, especially in smaller rooms.

(2) More stable compressor speed​

Stable coil temperature =
more reliable dew formation on coil =
better moisture removal.

(3) SRK indoor units have:​

• large heat exchanger surface
• better refrigerant distribution
• slower fan minimum speed
  These are ideal for mould suppression.

(4) Daikin’s main weakness​

Daikin multi-systems are optimised for efficiency →
They often run warmer indoor coils to save energy.

This results in:
slower humidity removal
more “still damp” feeling
higher mould risk on walls, wardrobes, leather bags, mattresses

5. Overnight Bedroom-Only Use (Real Singapore Scenario)​

✔ Winner: Daikin for electricity​

✔ Winner: MHI for comfort, dryness, mould control​

If running only 1–2 bedrooms:

Daikin strength​

• lowest minimum compressor load (0.27 kW)
• lowest electricity draw
• excellent whole-night efficiency

Daikin weakness​

Because its minimum load is LOW, the system tends to:

• run the compressor warm
• reduce condensate formation
• humidity creeps back up after 2–3 hours
• airflow stays “dry but not dehumidified” → bad for eczema

MHI strength​

Even with higher min load (0.4 kW), MHI maintains:

• colder coils
• better condensation
• stable humidity at 70–75% RH down to 55–60% depending on setpoint
  This is the ideal RH range for skin comfort and mould prevention.

6. Cooling Performance by Room Type​

Bedrooms (small rooms)​

✔ MHI wins

• more cooling power in small volumes
• faster drop in humidity
• quicker achievement of steady, gentle airflow
• ideal for sleeping comfort

Master Room (largest room)​

✔ Daikin wins

• 3.59 kW delivered
• better for large open spaces
• better if master room west-facing, afternoon sun, or large windows

7. Air Cleanliness & Coil Hygiene​

Mitsubishi Heavy​

✔ Best coil cleanliness in real use

• hydrophilic coil surfaces
• stable coil temps → less condensation cycling → less slime
• more logical fan-dry mode

Daikin​

✔ Good filters
⚠ Coil tends to run warmer → condensation cycles can cause musty smell faster if maintenance is delayed.

---

8. Compressor & Reliability Considerations​

Mitsubishi Heavy​

✔ Overbuilt compressors
✔ Very stable current draw
✔ Minimal surges
✔ Runs cooler internally
→ long lifespan, especially in Singapore humidity
→ fewer PCB failures

Daikin​

✔ Excellent efficiency
⚠ Higher surge current (up to 14.5A)
⚠ More sensitive to distribution imbalance
⚠ Maintenance-sensitive to keep efficiency high

---

9. Electricity Cost​

With your usage (3 bedrooms regularly):​

• Daikin uses about 10–18% less electricity
• MHI provides better humidity and comfort at slightly higher cost

Use a few AI since it free.

I find gpt sometimes not as detail

Someone posted this before, the rarer ur ac is, the harder to find spare parts and the tech might not be as skilled as the ac on how to repair

Depend on your choice to go for the most engery saving or the most btu

Most engery saving goes to Fujitsu (system 1, I focus on that as I buying it)

If u want the most btu nothing beat a dual condenser setup

Dalkin skyair series 32k btu + system 4 with 3 fcu

You have plenty of btu

I guessing your extended warranty by GC?

 

[Mecisteus]

thanks for ur insights! yea, I actually prefer spending more now for a system that is more lasting. but this model if I m not wrong just debut in jul so am relying on brand name for confidence

yes it is the scm40ys-w, 3xSRK13YYS + 1XSRK24YYS, they claim free upgrade from 9btu to 12btu for all fcus so I just took it up. 24btu one is for the living room with top up of $150

I compared it to the equivalent starmex n daikin seems to be about the same in terms of cooling performance and functions wise. am also drawn to the better looking fcus n wifi control...aghh so many things to consider. guess I'm getting u guys insights to correct my sense of priority haha

Won't go wrong with Daikin or Mitsubishi Electric. Each has their own strengths.

Can consider the opinions of aircon repairmen also. Most will advise ME because of the availability of parts.

Can consider other brands if they are substantially discounted.

 

[The_King]

Sharing what i know and learn so far, i try make it in point form to keep it simple:



contact 4 company:
letscool
amyth
aircon rescue
newway





my shortlist are simple:
look at google bad review (or any other source) only, the bad review date last posted how often bad review is posted
materials





materials :
letscool quote me : SWG22
amyth quote me : SWG22
aircon rescue quote me : SWG21
newway quote me : SWG21

the price all 4 are less then $40 different

all other almost the same of 1/2inch, copper wire almost same core and number of wire etc..... so my shortlisted are aircon rescue and newway as they quote me the correct materials (i started a thread talking about the copper thickness)





i choose newway based on google (or any other source) bad review feedback or lack of (as explain) aircon rescue no cause not much of any feedback from any source (it a new company)

after the piping is 80% done, i go take picture . i take this drain pipe like very little insulation when he saw me take picture he redo (or maybe he already want to redo i dont know) but happy he did redo cause the next 3 to 4hr doing the piping from 3.30pm until 6.30 to 7pm++++++

more checking, so far so good after that strange redo

from here on, all is good, everything is good, dont even need to open mouth liao
drain pipe no join connector but using heat to pipe and install with insulation at blend area

video about layout(before drain pipe redo), vacuum and doing the soap test to check leak , installer auto use soap to check for leak on their own unlike my first installer who dont even vacuum and do the soap test


video link:
https ://imgur. com/7fYCGkg
https ://i.imgur. com /7fYCGkg. mp4



last step, they even add rubber on the condenser leg, (this is not needed at all, some may first it a cons if the rubber wear out) i feel adding it, doing the soap test show their professionalism

workmanship issues take time to show up, can be weeks to year. but so far everything look good for now

 

[UchihaSasuke]

Sharing what i know and learn so far, i try make it in point form to keep it simple:



contact 4 company:
letscool
amyth
aircon rescue
newway





my shortlist are simple:
look at google bad review (or any other source) only, the bad review date last posted how often bad review is posted
materials





materials :
letscool quote me : SWG22
amyth quote me : SWG22
aircon rescue quote me : SWG21
newway quote me : SWG21

the price all 4 are less then $40 different

all other almost the same of 1/2inch, copper wire almost same core and number of wire etc..... so my shortlisted are aircon rescue and newway as they quote me the correct materials (i started a thread talking about the copper thickness)





i choose newway based on google (or any other source) bad review feedback or lack of (as explain) aircon rescue no cause not much of any feedback from any source (it a new company)

after the piping is 80% done, i go take picture . i take this drain pipe like very little insulation when he saw me take picture he redo (or maybe he already want to redo i dont know) but happy he did redo cause the next 3 to 4hr doing the piping from 3.30pm until 6.30 to 7pm++++++

more checking, so far so good after that strange redo

from here on, all is good, everything is good, dont even need to open mouth liao
drain pipe no join connector but using heat to pipe and install with insulation at blend area

video about layout(before drain pipe redo), vacuum and doing the soap test to check leak , installer auto use soap to check for leak on their own unlike my first installer who dont even vacuum and do the soap test


video link:
https ://imgur. com/7fYCGkg
https ://i.imgur. com /7fYCGkg. mp4



last step, they even add rubber on the condenser leg, (this is not needed at all, some may first it a cons if the rubber wear out) i feel adding it, doing the soap test show their professionalism

workmanship issues take time to show up, can be weeks to year. but so far everything look good for now

This is your 2nd air con installation? I remember 1-2 years back you just installed your air con system.

 

[The_King]

This is your 2nd air con installation? I remember 1-2 years back you just installed your air con system.

This is for family member which I help oversee


For mine ai say prefer to have a min 5 yr age gap, so it q2 2027, I think if can prefer q4 2026

 

[blastmachine]

I've read about newly installed AC units lines being vacuum by their contractor. This, I believed, is a step in the correct direction for any home AC installation locally or in this region (rather than purging AC lines with gas).

But in my opinion, vacuuming alone without leak test does not fully fulfill it's purpose. A micron meter should be use to monitor the vacuum in the line (some say pressure gauge should be sufficient with the in hg readings). Then make sure the readings stabilize after the pump is switch off to detect any vacuum leak for about 30mins. Soap water to be use for leak test as well, especially at the joints area, to detect visible leakage apart from reading the micron meter.

Additionally, prior in vacuuming step process, the lines should be filled with N2 and pressure tested at 200 psi at least to detect for high pressure leak for a few minutes. Same soap test to be done at the joints as well.

My point being, does any contractor here in SG does the below steps process?

1) Installation of compressor and AC lines
2) Fixed lines to FCU.
3) Filled line with N2, positive pressure test.
4) Discharge N2, vacuum line using Micron meter, vacuum leak test.
5) Filled up the lines with refrigerant by opening the valve at compressor side.
6) FCU testing to check the coldness, top up gas if necessary.

Step 3 and 4 usually omitted by contractor in place of gas purging, still quite common. But recently, step 4 is done by vacuuming the lines without monitoring the vacuum level or leaks. So if there's a leakage, gas will leak n air will still contaminate the lines. That's why some of us, our Aircon will not be cold within weeks, months or couple of years.

Sorry for the long post need to say the above. Still looking for a contractor that does the above steps as standard practice.

 

[The_King]

I've read about newly installed AC units lines being vacuum by their contractor. This, I believed, is a step in the correct direction for any home AC installation locally or in this region (rather than purging AC lines with gas).

But in my opinion, vacuuming alone without leak test does not fully fulfill it's purpose. A micron meter should be use to monitor the vacuum in the line (some say pressure gauge should be sufficient with the in hg readings). Then make sure the readings stabilize after the pump is switch off to detect any vacuum leak for about 30mins. Soap water to be use for leak test as well, especially at the joints area, to detect visible leakage apart from reading the micron meter.

Additionally, prior in vacuuming step process, the lines should be filled with N2 and pressure tested at 200 psi at least to detect for high pressure leak for a few minutes. Same soap test to be done at the joints as well.

My point being, does any contractor here in SG does the below steps process?

1) Installation of compressor and AC lines
2) Fixed lines to FCU.
3) Filled line with N2, positive pressure test.
4) Discharge N2, vacuum line using Micron meter, vacuum leak test.
5) Filled up the lines with refrigerant by opening the valve at compressor side.
6) FCU testing to check the coldness, top up gas if necessary.

Step 3 and 4 usually omitted by contractor in place of gas purging, still quite common. But recently, step 4 is done by vacuuming the lines without monitoring the vacuum level or leaks. So if there's a leakage, gas will leak n air will still contaminate the lines. That's why some of us, our Aircon will not be cold within weeks, months or couple of years.

Sorry for the long post need to say the above. Still looking for a contractor that does the above steps as standard practice.

the only one that does all the above you mention are own ppl do for own family member or very close family members

my co and cousin who share info with me when i ask them for contact . they share what they do and i ask if can share contact, they all say they are not vendor and only help own ppl do


for me exp, i try asking 3, some ac vendor do and charge at that time i believe $300 to $400 to pressure test during installation


nowadays i plan my ac as in Planned obsolescence. get better materials like larger trunking, 1inch thick insulation (1 whole pc of insulation not those section by section which need to rejoin back when installing) , 25mm drainage pipe, swg20, shortest path if can (else ac blow directly at me, if cant use stand fan to direct airflow)

so when ac spoil (say workmanship no issues, no conden, no gas leak), replace new FCU and new condenser only (usually if you replace those 2 only, some will do pressure test) and reuse all other

someone share last month, he reusage back the materials and then replace new fcu/ condensor after climate, he paid $300 or $400 only

that my aim

 

[Mecisteus]

Anyone bought a handheld pump for aircon cleaning ? Are they durable ? Can last long ?

I have the box type dc pump. Used a couple of times but not so portable. I would like to try this type

https://sg.shp.ee/yqhyX8Z

 

[The_King]

MY daikin many parts are from midea even compressor also midea or china parts

i wonder SG daikin also same? if so might as well save cash and buy midea

 

[cc2mss5]

I'm looking to replace my existing aircon

shortlisted midea and have asked one of the installer whom also using midea. his only complaint is compressor noise

hopefully my job is smooth


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