Aircond Flushing

Recently, I've sent my own car to an air conditioning specialist on the high recommendation of one of my suppliers. My a/c system had problems such as :

-irregular cut on/off
-sluggish engine when a/c kicks in
-warm... doesnt cool down after car is parked under the sun for some time
-not as cold as it used to be last time

I replaced my compressor, drier, expansion valve, and added a high speed fan to my system as it wasn't as cold as it used to be. Furthermore, I was eager to try this service out. My aircond system was not as cold as it used to be after I plonked the 'half-cut' in. I was thinking it was due to the new engine heat affecting the whole system.

Therefore, I decided to do a flush as i've never done it once before throughout the life of the vehicle. This particular shop uses a state-of-the-art machine that costs a whopping RM28,000.00 thats gonna do the flushing job.








The boss/ technician, Dahari, dia a very good job as I, as a fussy pot, myself observed every single step and task performed and couldn't find any flaws in his workmanship. Very carefully, he performed the below task :

-Preparation
I briefed him on what was changed earlier (such as expansion valve, receiver drier) to make his job easier in troubleshooting. My coil was taken out for cleaning 5months ago.
Dahari started my car and my a/c system to monitor the cooling capacity of my system. It seems that it wasnt really cold even after an earlier shop added some gas into it. We came to two conclusions, we suspect there may be a leak in the system, or the a/c shop just simply didn't put in enough refrigerant in the system.

Process 1 - Troubleshooting
He then switched the Flush Machine on and hooked the pressure hoses onto my a/c service ports. Immediately, he recovered all the refrigerant (a/c gas) and oil that's left in my system back into his machine and went on to the Vacuum process to remove all air thats in the system. Weirdly, I noticed that he closed the valve on the service ports when he vacuum was done. I asked him why. Pleasantly, he explained to me "Vacuum was done on my hoses and service valves first so that I would know if my own hose is leaking, and not your system. We will do a vacuum on our hoses, and switch it off for ten minutes. If the meter on the machine goes from negative pressure towards atmospheric pressure, it means that I have a leakage in the hose".

Once he confirmed that there wasn't any leakage in his hose, Dahari then opened the service valves that was attached onto my service ports to perform another vacuum process, this time on my entire a/c system. Once the vacuum was done, it was switched off again and we waited for another ten minutes. Hhmm... no leaks.


Process no. 2 - Troubleshooting (2)
Vacuum done. Dahari then set the machine to a certain amount of refrigerant and recharged my a/c system and unhooked the machine hoses from my service ports. The car was then started to check if there was any leaks with a specially calibrated leak detector. He even faced the leak detector onto my a/c vents to detect for any leakage of the R134a regrigerant from the cooling coil(which, other workshops will just opt to take the whole cooling coil off and pressure test it in a tub of water).

We went on to check other joints,seals, service ports for any leakage with the leak detector. Apparently we couldn't find any leak.




Final conclusion, there was no leakage in the system at all.


Process 3 - Flushing
Dahari hooked on the machine hoses again and recovered my refrigerant again. This is where the flushing process starts ;

1. Engine switched off
2. 8-step flushing process starts with the touch of a button on the machine
3. Aircond refrigerant in liquid form circulates the whole system in one direction (say... clockwise).
4. Step 3 repeated several times.
5. Refrigerant now goes anti-clockwise as a more effective method of cleaning.
6. Step 5 repeated several times.
7. Process stops when the machine cleans the whole system entirely.
8. Precautious measures were taken to prevent the receiver drier and cooling coil from 'icing', which is bad for the system.



Process was done after close to two hours.





Conclusion : The above picture shows the color of refrigerant that came out of the system. This is a 100% flushing process mind you. The original color of the refrigerant i put in was pure fluorescent green. Look how it is now after only three months of usage? Water and specks of dust could be seen closely.


Process 4 - Long Vacuum

Vacuum process was started again, this time, was 20mins, to really ensure that there was NO air in the system. The air in the system, the better the purity of the refrigerant in the system without any presence of air.

Process 5 - Recahrging

After vacuuming the system, carefully, Dahari inserted new compressor oil into the system. FULLY SYNTHETIC COMPRESSOR OIL (46 viscosity as per specification) was used this time. Not cheap.





Another thing that other shops would not do :

While vacuum still in process (last 3minutes), Dahari closed the low pressure valve and disconnected the machine hose. Vacuum is still present in the system and the machine hose. He connected the synthetic oil along with a press gun and nozzle into the low pressure service port.



He opened the valve on the nozzle thats connected into the port and the oil automatically gets sucked into the system from vacuum effect. Keep in mind that the High pressure hose is still connected and is vacuuming the system. That way, vacuum pressure has not drop a single bit yet.

Nozzle valve was closed and disconnectd after 150ml of oil was put in.


The last step would be recharging the whole system with 550gm of refrigerant before firing up the car.

Dahari connected back the low pressure machine hose back to the service port. Keep in mind that the valve is still closed.
By selecting 'recharge' mode on the machine, he pre-setted the volume to 550gm of refrigerant/gas as per manufacturer specification.


This is another part which other shops would not do :
Recharging step activated - he loosened the machine hose from the valve at the service port to allow air to flow out and to allow refrigerant to flow through and fill up the hose, tightened the hose back to the head, AND THEN OPENED THE VALVE for the refrigerant to go through the service port.

The above step was done so that present air thats in the machine hose does not go into the system. If not, this beats the purpose of vacumming the system already.



Final Step - Firing up the car (finally! woohoo!)

All hoses disconnected and machine was switched off. We started the car with the aircond switched off. Dahari carefully switched the a/c compressor on and off several and numerous times in order for the compressor oil to go through the compressor but not run the compressor yet. This is to ensure there is sufficient oil in the compressor when it starts running (damage MAY occur if this step is not done). Its the same process as starting an engine without the fuel line hooked in to get oil flowing through the engine just after you overhaul your engine.


Conclusion :
My car was freezing all the way to Subang when we were done. I tested my car in the sun the next morning/afternoon and noticed that the cabin cools down much faster than it used to be, ven if the car was parked under the sun for an hour.

This shows that the refrigerant in the system is SUPER pure and becomes as cold as it was supposed to be when compressed by the compressor.
Pricing is a bit pricey, but taking into consideration the price of the machine, price hike of a/c refrigerant, synthetic oil was used,the rental of the workshop, the time needed to perform this task on just one car, I wouldn't mind forking out this amount of cash for something that we need most in Malaysia, good a/c.c.

It made a world of difference, and will do so even on new cars. Some cars claim that the rpm doesnt drop when the compressor kicks in due the the quality of the oil used in the compressor.

Needless I must say, this is the BEST service I've ever experienced so far.

Thumbs up to Air Cond Station in Shah Alam, Section 7!!


Overall Rating : 10/10
Pricing : RM450.00 onwards (not incuding labour and parts to replace whatever that's necessary)