Mistubishi Mr. Slim compressor problem

I have Mitsubishi Mr. Slim 12000 BTU. Its compressor heats up so much that you can not touch the steel underneath compressor (outdoor unit). Afterwards it switches-off (but FAN of outdoor does not).

I have done complete service including gas replacement etc. There is not electricity problem.

what could be the possible reason & any suggestions to resolve it.

I am facing similar problems since last one month. One expert asked for maintenance, got money, and went away.

Second expert filled gas, got money and gone.

Third Export removed heating system, suggested a shade on outdoor unit to save it from sun-light, got money and now nowhere.

4th expert blamed compressor and asked for replacement with new one and suggested for a cheaper solution "Dawlance" compressor. We purchased it, he fixed it, AC was okay only for two hours, then converted into fresh air (room temprature circulation) and then hot air.

Now the gentleman is blaming to voltage as it is not sufficient to pick the load of AC. While other 8 ACs are working fine on the same load, (I think it is light of truck, as now I am suppose to check electricity of whole building, wow what a good trick by the expert).

Now we are going to arrange a stablizer to give him continue power supply of 220. Current voltage is 205-209. Since last 4-5 days we are busy in these negotiations which are not ending.

The problem is that AC when started, works fine only for two hours.

Another expert says, he can fix the problem, but the question is, now again I have to pay whereas I already spent half price of a new AC.

Hussain (hussain@voiceteltech.com) 0300-8503800

for both the above 2 posts :

there can b 4 reason of tht problem

number 1-

make sure that the gas valves (at the side of the outdoor unit) is fully open , it opens with the L key .

number 2 -

have you chekd the capacitor in the outdoor unit ?

replace it and insha ALLAH it will work fine.

number 3-

chk the relay of the compressor , bcz of loosing in the connectors OR the loosing internally in the relay causes this.

number 4-

if you charged the gas make sure tht the Gas is fully filled and it is taking proper load when the the compressor is working if it i staking less amperes then it means the gas is less and thts y the compressor is running freely and thus heating up .

voltage should not b the prob as all other a/c are working fine as u mentioned.

Wrong forum, Its the topic of General Tech.

Finally after getting various verdicts from various mechanics I called the Mitsubishi service center. The gentleman there was very kind and told me solution which was very simple. He notified that there could only be two possible reasons for that

1. Outdoor condenser coil is dirty and choked.

2. low GAS.

As per his advice I first cleaned outdoor unit condenser coil with blower and then washed it with water (little bit pressure). My AC is now working like new.

You just have to make sure that compressor part & electrics does not get wet. You can follow below sequence:

1. open the top cover.

2. open the front cover (the FAN side).

3. use blower to clean the coil. Remember to do this from inside-out i.e., blow from the FAN side so that dirt goes out from where it came from.

4. use pressure water to clean the coil (must save compressor & electric from getting wet).

5. use blower to dry the coil and any other wet parts.

6. wait for 4 to 5 hours as a precaution (may be electric & compressor got wet and you don't know).

7. Re-assemble the outdoor.

8. Enjoy......

The person from Mitsubishi (WHO TOLD THIS) is engineer with 32 years experience in same field.

Dear A. Q. Sahib Assalam-o-Alaikum,

I shall be grateful if you provide me the contact details of Mitsubishi expert you talked with. As my problem is still there.

Thanks in advance.




Dear Hussain Sb,

Below is the phone number of Mitsubishi Service center (Rawalpindi)


You can ask for Mr. Zulfiqar (I guess) who is the center manager.


Abdul Qayyum

Wow such a simple solution. Lesson learned is periodic maintenance is a must!