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Air conditioning - Any recommendations please??

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Old 06-01-2017, 09:34 PM   #9196
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Dear ALL,

Beware of SELF advertising on MHI air con ( Mitshubishi Heavy Industrial),

Below is my personal experience with MHI air con

I have a system 4 MHI using for 3.5 years. Now having problems cannot turn on, lights on the fan coil have orange blink four times follow by lights in green & orange blink 4 times and this repeat itself again and again.
Have 4 contractors to check and everyone told me a different faults
First one told me gas NOT enough, very confident. After refilling gas, problems still exists
Second one told me gas value cannot open fully, after changing, problems still exists
Third one told me Thermostat spoilt, after changing, problems still exists
Four one ( also the SOLE AGENT told me the dirt inside the gas pipe that block the gas flow fully, Charge me $80 SDG for troubleshooting ONLY. NOT repair done, if repair, this $80 cannot take into account.
Very bad experience.
Please do not buy Mitsubishi Heavy Industries air con for this model. SOLE AGENT office very PROUD guy.
This is the model, PLEASE DO NOT BUY THIS MODEL, only last 3.5 years
SCM80ZJ-S ( compressor )
SRK60ZJ-S ( fan coil )
SRK35ZJ-S ( fan coil )
SRK25ZJ-S ( fan coil )
SRK25ZJ-S ( fan coil )
PLEASE DO NOT BUY, bad after sales support from their SOLE AGENT. Very PROUD PROUD attuide.
Really hope their service improves..just got my warranty cert today two days after the installation was completed..


In addition, my installer gave me two years warranty on installation..

Last edited by mlangelo; 06-01-2017 at 09:37 PM..
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Old 06-01-2017, 10:04 PM   #9197
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Hi,

In this case, there is a noise level issue which can be contributed by the following:

1. The sound level of the air conditioner system
2. The sound level from the air conditioner piping (vibration).
3. The sound level from the combination of both the air conditioner and the piping.
4. The sound level from the air conditioner mounting bracket (if used)
5. The perceived loudness by the person hearing the sound.

Focusing only on the air conditioner, the 5 ticks is having condenser sound level of 56dB as specified. Though it is louder than the 2 ticks, it does not mean that it is a noisy equipment.

On this, is 56 dB consider as loud? How loud in normal situation is 56 dB? Is this loudness out of the normal experience that would annoy someone?

Well, according to the chart below, 56 dB is as loud or as soft as during a normal conversation. Is this too loud? Will it annoy someone?

http://www.noisehelp.com/noise-level-chart.html

http://chchearing.org/noise/common-e...-noise-levels/

Well, I think it is unlikely that someone will be annoyed by such sound level. 56 db is around our conversational speech of 60 dB.

Readers can download a dB meter application from Playstore and you will released that 56 dB is really not loud at all. (Note: I am aware that the dB meter that is download from Playstore is not calibrated. It is only used for comparison).

So if your condenser is creating noise that affect your neighbours, then it will be good to check whether it is meeting its specification or not.

Maybe you are having a defective product right from the start. Good to resolve this problem before it becomes a major defective with expensive repair cost after the warranty. Covering the condenser with a acoustic material is not solving the problem. It does not make the defective product meet its specification.

By the way, the video attached in your message is from a 40kVA genset (generator of 32kW). It is difficult to confirm that the sound that is from the video is the same loudness as shown on the dB meter, as there are other sounds, such as environmental sounds and also the video mic level setting (not the dB meter setting) and also my computer speaker setting.

The above are my opinion and hope that they are helpful.
Hi,

To feel how loud is 59 dB, readers can do the following:

1. Download a dB meter application from PlayStore.
2. Go to youtube and search for "air conditioner condenser noise" and select those videos that only have the condenser operating sound (ie exclude voice and music).
3. Play the video, place your hand phone over your pc, and read the dB meter sound level when the compressor is in operation.
4. Increase or reduce the video by adjusting the computer volume to reach 59 dB.
5. When the dB meter shows 59 dB, this is the loudness of the condenser sound that you will likely hear when you are near it.
6. Walk about 3 to 4 m away from your computer and hear the sound level.

You can then decide whether 59 dB is loud or soft at a certain distance away. You may also wish to bring the dB meter when you move away from your computer and check its reading.

7. Now you can close all your windows and door to remove any environment noise and check your dB meter again for 59 dB, you may realize that the noise sound louder even though it is 59 dB. So is the condenser noisy? Maybe but is it within spec. Yes!

If your condenser sounds louder than this level. You may wish to contact the manufacturer to rectify it as soon as possible during its warranty period.

Try it out for 49 dB.

Hope that the above is helpful.
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Old 07-01-2017, 12:21 PM   #9198
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Installation checks #1 - no jointing of new pipe allowed.

Hi,

If you are installing a new air conditioner, and had opted for new piping, than it is important that you observe the installers to ensure that they do not joint the pipes.

Discuss this requirement with the seller and have it written in your order that no jointing is acceptable except at the FCU and Condenser and to use flared joints. Some worker braze the pipe at the FCU to save them the work to properly route the pipes.

Brazing of the pipes is not acceptable and you should be consulted if worker which to do brazing. Never Never allow them to braze the pipes.

As you are paying for the new pipe, there is no reason why the new pipe need to be jointed. New pipe comes at a length of 15m and this is sufficient for most houses in Singapore.

Jointing of new pipes are done when workers salvage left over new pipes from other installation to save cost. Some pipes may have a few joints from shorter pipes. When pipes are inserted into the insulation, it becomes difficult for the customers to check for brazed joints. Workers will normally insert the pipes into the insulation when you are not around or during lunch time when no one is watching them.

Have it in your agreement that you wish to inspect the new pipe before they are inserted into the insulation.

In Singapore, all air conditioner joint that are brazed are inappropriately done, ie without the use of nitrogen gas and as a result may cause serious failure to the system with expensive repair or even complete change of the whole system.

Attached is a link showing what happened when copper pipe is brazed with and without nitrogen.

https://youtu.be/Bpqxbc9XQ5Y

Air conditioner system consist of parts that have very fine holes in the control devices and scaling from brazed pipe without using nitrogen can easily choke the system.

So NEVER NEVER allow your new pipes to be brazed joint by the worker at any cost. Stop them, or reject the pipe and show them your agreement that you have with the seller.

The above are my opinion and hope that they are helpful.
dEv_ and Ulupandan like this.

Last edited by dachee; 07-01-2017 at 07:42 PM..
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Old 08-01-2017, 12:51 AM   #9199
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Hi, your image cannot be opened. Pls provide the link again.

https://imageshack.com/i/plPe20Zoj
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Old 08-01-2017, 01:03 AM   #9200
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Is it advisable to use the daikin pro shop for purchasing and installation? Have to decide on aircon soon since my renovations are staring.

Any difference between the different pro shops? Are they manage by daikin directly or are they sub cons?
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Old 08-01-2017, 01:47 AM   #9201
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https://imageshack.com/i/plPe20Zoj
Hi,

Sorry for the late reply.

Have a look at this: https://imageshack.com/i/pmG0SSVDp

I am assuming that there is a beam over the corridor from the kitchen to the living room. This FCU may have to be higher than the one in the living room. The normal height of the FCU is 8ft from the floor.

Do let me know if there is no beam there, so that I can look for alternative location.

You have a choice of one system 3 (bedrooms) and one system 2 (living and dining) or just one system 3 for the bedrooms. Living and dining no air conditioner.

If you are using 2 systems, then it is good to check that your house is allowed to install 2 power points for the 2 condensers.

Also let me have your comments.

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

Last edited by dachee; 08-01-2017 at 09:12 AM..
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Old 08-01-2017, 02:00 PM   #9202
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Is it advisable to use the daikin pro shop for purchasing and installation? Have to decide on aircon soon since my renovations are staring.

Any difference between the different pro shops? Are they manage by daikin directly or are they sub cons?
I'm currently going for an installation by a Pro Shop. Fortuna, to be accurate. It's interesting to see how few reviews there are for these shops here on the forums. However, they should be a little more dependable given that they are, after all, the authorised Daikin installers.

I'll post my findings after they install the piping this coming weekend.
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Old 08-01-2017, 02:02 PM   #9203
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Hi,

Sorry for the late reply.

Have a look at this: https://imageshack.com/i/pmG0SSVDp

I am assuming that there is a beam over the corridor from the kitchen to the living room. This FCU may have to be higher than the one in the living room. The normal height of the FCU is 8ft from the floor.

Do let me know if there is no beam there, so that I can look for alternative location.

You have a choice of one system 3 (bedrooms) and one system 2 (living and dining) or just one system 3 for the bedrooms. Living and dining no air conditioner.

If you are using 2 systems, then it is good to check that your house is allowed to install 2 power points for the 2 condensers.

Also let me have your comments.

The above are my opinion and hope that they are helpful.
yes there is a beam along the the foyer in the living room.

My plan

Living Room aircon above the entrance door beam - pipe trunking from TOP to kitchen down straight to yard then to ledge

MBR aircon above toilet door - pipe trunking all inside MBR false ceiling out to ledge

Bedroom 2 above door - pipe trunking TOP to the walkway beam to common toilet false ceiling then to MBR false ceiling to yard then to ledge

Bedroom 3 above door - pipe trunking TOP to the walkway beam to kitchen TOP then down to bottom straight to yard then to ledge

Thank you
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Old 08-01-2017, 03:32 PM   #9204
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Cheers, do let me know your experience with them, can’t seem to find any shop recommendations. Might just go with them since u have experience

I'm currently going for an installation by a Pro Shop. Fortuna, to be accurate. It's interesting to see how few reviews there are for these shops here on the forums. However, they should be a little more dependable given that they are, after all, the authorised Daikin installers.

I'll post my findings after they install the piping this coming weekend.
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Old 08-01-2017, 03:35 PM   #9205
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weather very hot today ><
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Old 08-01-2017, 08:03 PM   #9206
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Hi,

If you are installing a new air conditioner, and had opted for new piping, than it is important that you observe the installers to ensure that they do not joint the pipes.

Discuss this requirement with the seller and have it written in your order that no jointing is acceptable except at the FCU and Condenser and to use flared joints. Some worker braze the pipe at the FCU to save them the work to properly route the pipes.

Brazing of the pipes is not acceptable and you should be consulted if worker which to do brazing. Never Never allow them to braze the pipes.

As you are paying for the new pipe, there is no reason why the new pipe need to be jointed. New pipe comes at a length of 15m and this is sufficient for most houses in Singapore.

Jointing of new pipes are done when workers salvage left over new pipes from other installation to save cost. Some pipes may have a few joints from shorter pipes. When pipes are inserted into the insulation, it becomes difficult for the customers to check for brazed joints. Workers will normally insert the pipes into the insulation when you are not around or during lunch time when no one is watching them.

Have it in your agreement that you wish to inspect the new pipe before they are inserted into the insulation.

In Singapore, all air conditioner joint that are brazed are inappropriately done, ie without the use of nitrogen gas and as a result may cause serious failure to the system with expensive repair or even complete change of the whole system.

Attached is a link showing what happened when copper pipe is brazed with and without nitrogen.

https://youtu.be/Bpqxbc9XQ5Y

Air conditioner system consist of parts that have very fine holes in the control devices and scaling from brazed pipe without using nitrogen can easily choke the system.

So NEVER NEVER allow your new pipes to be brazed joint by the worker at any cost. Stop them, or reject the pipe and show them your agreement that you have with the seller.

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

So NEVER NEVER allow your new pipes to be brazed joint by the worker at any cost. Stop them, or reject the pipe and show them your agreement that you have with the seller.

- so it means when my bedroom aircon piping is more than 15m..then my room cannot have aircon inside.

In Singapore, all air conditioner joint that are brazed are inappropriately done

- any prove to show??
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Old 08-01-2017, 08:56 PM   #9207
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So NEVER NEVER allow your new pipes to be brazed joint by the worker at any cost. Stop them, or reject the pipe and show them your agreement that you have with the seller.

- so it means when my bedroom aircon piping is more than 15m..then my room cannot have aircon inside.

In Singapore, all air conditioner joint that are brazed are inappropriately done

- any prove to show??
Hi,

There are alternative methods of jointing pipes other than brazing and one common method is flared joint. If you need more than 15m of pipes, you still can joint them but not by brazing.

However, if you accept brazed joints, it is not of my concern if your system failure in future. It is your choice.

Most systems have pipe length limitation. Some 20m others 30m.

If you think that there are installer/s who braze the air conditioner copper pipes appropriately, do let us know who and how it was done that you think is appropriate.

Maybe STL Air Conditioning can show us how they do their brazing on a video.

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

Last edited by dachee; 09-01-2017 at 09:04 AM..
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Old 09-01-2017, 05:45 AM   #9208
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Just installed piping over the weekend..
Is this ok?

https://imageshack.us/i/poKnIIfKj

Thanks!
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Old 09-01-2017, 07:51 AM   #9209
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Just installed piping over the weekend..
Is this ok?

https://imageshack.us/i/poKnIIfKj

Thanks!
That's just the point right before the fan coil unit, so it's a little hard to tell if the whole system has been installed appropriately.

I think you can only determine if it's alright by observing the entire installation process, and noting if they're doing anything that raises alarm bells such as:

- Brazing copper pipes together
- Sharing insulation of copper pipes from the condenser
- Tearing the insulation

Out of curiosity, which A/C company did your installation?

Last edited by Quantom; 09-01-2017 at 07:58 AM..
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Old 09-01-2017, 08:40 AM   #9210
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Just installed piping over the weekend..
Is this ok?

https://imageshack.us/i/poKnIIfKj

Thanks!
Hi,

The link shows an insulated pipe photo at the FCU. The FCU consist of the evaporator coil with 2 ends, one incoming and another outgoing. The incoming pipe is smaller, carrying liquid refrigerant while the outgoing pipe is larger, carrying refrigerant gas back to the condenser.

Both these pipes are placed together in one insulation inside the FCU. It is normal for installer to group both the smaller and larger pipe from the condenser together in one insulation as it get nearer to the FCU to joint to the respective pipes in the FCU that are in one insulation.

It is good practice to observe the installer during installation to ensure that the pipes before this grouping into one insulation are actually individual insulated pipes. This grouping should be as short as possible. There is no standard to date as to the length of this grouping, it should be done just to allow the pipes to fit nicely within the FCU. Two individual pipes may likely be too large for the available space within the FCU.

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

Last edited by dachee; 09-01-2017 at 09:02 AM..
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