Hi all, recently I had a Mitsubishi Heavy Industries system 4 inverter installed. However, I found that during operation, I can hear a soft strange and slightly high pitched "eeeee" whistling sound. The sound can be heard more clearly when the room is quiet or when you are right under the air con unit.

I concluded that it's not the fan noise as the whistling sound doesn't change or become louder or softer when I switch the fan speed to different levels. I'm not annoyed by the fan noise but rather the "eeeee" whistling sound that can be heard during operation. I tested it with all 4 units for my system 4 and all have the same "whistling" sound.

I'm satisfied with the air con but the "whistling" sound can be rather annoying at times especially when you are trying to sleep.

The previous air con i had (mitsubishi mr slim system 3), I don't recall hearing this strange sound during operation. Is this abnormal? Is it a problem with installation or the compressor/air con itself? anyone with mhi air con or have similar "probs" can feedback to me? Thanks!

My compressor : scm80zg-s

air con units : 3 x skm28zg-s

1 x skm50zg-s

Edited October 8, 200818 yr by jevil

Hi,

I have same encounter as you. On the day of installation, they came very late and no enough time to run thorogh test. Two days later, when I have time to test the new MHI aircon, i noticed all 3 indoor unit produce "eeeee" kind of high pitch noise. It is especially annoying in quiet ambient envirenment. I cannot image how one can sleep well with it. My aircon specs:

MHI System-3 Inverter

Outdoor: SCM60

Indoor: SKM28 x 3

Is your aircon also from same company xxxx Tech?

I'm yet to experience such irritating sounds.. not bought fm xxxx tech

IS the sound just happen when you just turn on the air con after that will disappear? If it does probably is normal as when you just turn on the unit the freon/gas is passing thru the piping. But if the noise just continuously then could be few possiblity. you might wanna ask your installer to come and redify or the agent itself

The "EeeEee" sound usually came from your blower's motor. You try push up on the right side of the aircon unit where the blower motor are located, see whether the will disappear when you push it up. If the sound disappear more or less your blower's motor is going to spoil soon and the sound will get louder and louder. Get your aircon man to check, I have a aircon techician no. Pm me if you need it.

Hi all, recently I had a Mitsubishi Heavy Industries system 4 inverter installed. However, I found that during operation, I can hear a soft strange and slightly high pitched "eeeee" whistling sound. The sound can be heard more clearly when the room is quiet or when you are right under the air con unit.

I concluded that it's not the fan noise as the whistling sound doesn't change or become louder or softer when I switch the fan speed to different levels. I'm not annoyed by the fan noise but rather the "eeeee" whistling sound that can be heard during operation. I tested it with all 4 units for my system 4 and all have the same "whistling" sound.

I'm satisfied with the air con but the "whistling" sound can be rather annoying at times especially when you are trying to sleep.

The previous air con i had (mitsubishi mr slim system 3), I don't recall hearing this strange sound during operation. Is this abnormal? Is it a problem with installation or the compressor/air con itself? anyone with mhi air con or have similar "probs" can feedback to me? Thanks!

My compressor : scm80zg-s

air con units : 3 x skm28zg-s

1 x skm50zg-s

What size of copper are you using? G22?

Hi,

I have used my for 11 month, so far i do not have this problem.

Hi,

I have used my for 11 month, so far i do not have this problem.

Where you buy the aircon?

copper size and foam type?

Hi,

Mine MHI System-3 is using G23 Copper pipe/13mm water pipe.

Last weekend Wo Kee Hong (MHI warranty service provider) has sent their technican to replace all 3 Fan motors for my indoor unit. But this kind of "eeeee" noise is still the same. Any ideas about what's actually going wrong? Please advise. Thanks.

hi,

Im also experiencing this problem. i bought it from BEST TECH also!!! i just got it fixed up 2 days ago!!! ****!! the "eeeEeeEeeEeEEEEeee" is making me sick~ especially at night! The techician from BT came, but he COULDNT hear that noise! Must be deaf.... And he asked us to refer back to the agent. What kind of customer service quality is this....

Poor workmanship and service. Crapped!!!

I really need help.. please save our EARS!!

BEST TECH !@#$%)#$%^&*(@#!@#$.

Cats & dogs may hear such high-pitched noise better if it's ultrasonic.

Is the noise super high-pitched 'air' noise? This may be caused by a leak of high pressure gas thru' a pin-sized hole in the copper pipes...

Or is it more like metal screeching noise?

Dear Friends,

To those who encounter low pitch sound (eeee...). Please contact MHI agent. The problem is coming from the motor itself. The defect batch motor is silver in color. The agent will change a new one (still warrantly with them) for free. It is white in color for the body of the motor. I have also encountered such problem, but the issue has been resolved!