Vehicle Aircon Problem/s

[jansonfinn]

Anyone knows how to troubleshoot vehicle aircon?

Why do I have to step on the accelerator pedal in order for cool air to come in? Idling of the engine won't be as cool as stepping on the accelerator pedal.

What is the problem here?

[Art]

sounds like gas leak..

if the car is above 3 yrs then should do a servicing...make sure filter clean..make sure eunff gas...make sure no leak etc...

google for this shop called tomika...at ubi...they the aircon experts.

[Adrianli]

The air-con compressor is driven by the car's engine by way of v-belt.

1) Ensure that the v-belt is in working condition, no wear and tear and no cracks on the belt.

2) Ensure that there is no slippage of belt.

3) Check no bubbles in the sight glass if the is one. If have bubbles means gas leak and air in the system.

4) Check the filter-dryer. Make sure that it is not too hot when touched. Too hot means it is choke.

5) Use a differential gauge and connect to the high and low connection points. Ensure that reading is in its working range. U will need to consult a car mechanic to help u on tis if u dont know abt A/C system at all.


These are just the basic checks which will not cost u much $$$. Further analysis is required if the above does not work. I used to repair a/c and refrigeration system onboard ship.

I strongly recommend Markcool from Woodlands Industrial Estate. Goggle for their location.

[P4cm4n2000]

air con belts

Hi Janson,

I had similar problem during the period when I was looking out for solution to the smell problem from my car air con system:

http://www.daddyhobby.com/forum/showthread.php?t=48360&highlight=air+con

My problem was, when at hi-speed, sometimes there's no cold air coming out from the vents. I have to quickly press the Air-con knob on/off several times and sometimes the air con comes back.

First, I went to "service" my air con system, kanna "con" (didn't know mah!) into
- flushing out the gas
- changed the orifice valve that sprays the freon gas inside the air-con system
- add filter
This was done at the car air-con/audio shop at Serangoon Gardens (Sim Lim Pte Ltd).

I agree with Adrian's advice. And I highly suspect its the belt that may be loose of worn out.

Finally I changed the belts (2pcs) at Shell (Serangoon Gardens), and the intermittent air-con issue is gone!

The belts are greatly worn out, with lots of cracks, hanging still with the outer layer wires that are built into the belts. looked like thism see thread #154 :

http://www.daddyhobby.com/forum/showthread.php?t=44136&highlight=kia&page=11

This explains why there's no cold air, as at hi-speed, there are slippages of the belt driving the air-con compressor. Also, last year I had battery charging problem as my battery indicator (bought from Autobacs) always shows low,
and it takes more cranks to start the engine).

Changing to new belt and ensuring tension will help drive the alternator properly to charge your battery.

If you hear squeaking sound when you start the engine, or idle, likely comes from the belts as I had this prolem before too.

Quick way is to drive down to Shell, ask the guys check for you, its Free!
I did my change at Serangoon Gardens' Shell (next to market).

Best to get your car checked & solve the root of the problem.

Hope this helps Bro!

Rdgs
John

Anyone knows how to troubleshoot vehicle aircon?

Why do I have to step on the accelerator pedal in order for cool air to come in? Idling of the engine won't be as cool as stepping on the accelerator pedal.

What is the problem here?

[td_04]

Why do I have to step on the accelerator pedal in order for cool air to come in? Idling of the engine won't be as cool as stepping on the accelerator pedal.

What is the problem here? [/QUOTE]

Hi Bro, reason why you need to feed in gas is bcause you are inducing your compressor by making it to work extra time....Simple troubleshooting you can immediately do is chk your cooling fan condition. Make sure both cooling fan is running when you switch on a/con, especially the one infront of your condensor (looks like radiator assy but way smaller). Most vehicle will have 2 cooling fan unless they are air cool......like some Porsche..

If the cooling fan is in working condition, I suspect your car is experiencing chocking. Most workshop will try and recommend you to replace items (receiver drier / expansion valve / god know what) but if thats my ride, I'll just ask them to carry out complete vacuuming and insert new set of freon gas and I'll monitor at my own end....

Please take my advise with a pinch of salt cause I'm not an engineer by profession...hehehe

Rgds,
Td_04

[BullTerrier]

Anyone knows how to troubleshoot vehicle aircon?

Why do I have to step on the accelerator pedal in order for cool air to come in? Idling of the engine won't be as cool as stepping on the accelerator pedal.

What is the problem here?

In the very old days, cars use FICD (fast idle control device) to control the car idling speed which will move up or down depending on the aircon compressor load which will come off and on during idling depending on the temperature set.

So your mechanic will tune your car to idle with load i.e. aircon on. Should the aircon goes off at this time cos the temp is cool enough, the idling speed will suddenly go up by a 100 or more rpm or revolutions per minute. If you should tune your car idling speed to be without load i.e. say 800 rpm, then when the aircon kicks in, the idling suddenly become too low and the car engine will vibrate as if its gonna croak.

These days modern cars come with advanced FICD control so this is not a problem any more. Your problem with the aircon not being cold i.e. the compressor not kicking sounds like a FICD related one. Get a aircon person to have a peek at it.

[jansonfinn]

Thank guys for the suggestion.

No wear & tear at the belt & no leakage of gas.

Went to 2 workshops n both workshop mentioned different components faulty. 1st workshop said that it is the compressor, 2nd workshop said that it is the orifice valve that need to be change.

So who to believe?

[Adrianli]

Did both workshop use the high-low gauge to test your a/c system??? If the readings are normal, I dont think its ur compressor faulty. What are the readings??? If I recall correctly, low side is ard 2-4bar and high side is ard 13-15bar.

Here is a pic of the gauge :




The orifice thing is the TEV, Thermal expansion valve, it is used to regulate the amount of refrigerent gas in the evaporator.

Here is a pic of your a/c system :

[pck]

Hi guys, seems to see a lot of useful advice here so I like to ask for advice for my problem with my car aircon too.

My car's aircon will sometimes stopped blowing air out from the air-vents completely. If I have switch my aircon off and then on again sometimes it will start immediately, but sometimes I will have to wait a while and then turn on before it will work again. The cooling is fine, just that it turns off by itself at times.

Any idea what could be wrong here?

[P4cm4n2000]

Hi guys, seems to see a lot of useful advice here so I like to ask for advice for my problem with my car aircon too.

My car's aircon will sometimes stopped blowing air out from the air-vents completely. If I have switch my aircon off and then on again sometimes it will start immediately, but sometimes I will have to wait a while and then turn on before it will work again. The cooling is fine, just that it turns off by itself at times.

Any idea what could be wrong here?

Hi Johnson,
Seems I had similar problem with yours too, intermittent on/off air-con.
Read my reply in thread #4.

One thing I learned from observation at Shell is, switch off all your radio, etc...and listen closely to the sound produced with your engine idle.
Look at the rpm gauge, mine is about 1000rpm (If I can recall correctly)
Switching on / off the air-con will cause the rpm to dip slightly, then back to normal idle speed.==> the mechanic said this shows the compressor is working fine. Likewise the guage Adrian mentioned have similar variation in pressure when you on/off the air-con.

From my quest to fix the air con problem, I think it really varies from car to car, ranging from:
- belt worn out (slippage to drive the air-con compressor)
- low-air-con gas
- stucked orifice valve
- air-con switch contact problem
- etc...

I've also learned that we need to "flush" the compressor from its old-oil after don't know how many years (sorry),
and top up with new compressor oil. Autobacs charge about S$80 for Air-con flush (see here: http://www.autobacs.com.sg/images/promo_image/jul08.jpg) as the mechanics mentioned about heating up the compressor due to the lack of lubrication and a damaged compressor is very expensive to change (i.e. up to $1000 each depending on car model)
Shell charges about $180 similar package. Both takes about 2hrs.
see here:

http://www.daddyhobby.com/forum/showpost.php?p=446153&postcount=158

I know its annoying to get the air-con on/off just when you needed it ! especially during hot days.....also, some air-con smells when you started the engine first thing in the morning...

Nevertheless, hope you find the root of the problem soonest Bro!
Basically if you look at the a/c system Adrian posted, we just have to "troubleshoot" one by one to narrow down the root.

one more thing to note is , whether is the blower working (underneath the glove bin compartment)...or is there particles stucked as it sucks air from the rear (inlet) where the passenger's legs extended.

Beter get more reputable service centres to help you out, like Shell or Autobacs....otherwise they anyhow quote you prices and change or charges extra just to profit.


Cheers!
John

[td_04]

If the cooling fan is in working condition, I suspect your car is experiencing chocking. Most workshop will try and recommend you to replace items (receiver drier / expansion valve / god know what) but if thats my ride, I'll just ask them to carry out complete vacuuming and insert new set of freon gas and I'll monitor at my own end....

Please take my advise with a pinch of salt cause I'm not an engineer by profession...hehehe

Hi Janson,

Read through my statement again and I almost knew what the aircon people / workshop will advise you cause it is almost SOP for workshops to answer (No pun intended)... Rgds to the TEV (Thermal Expansion Valve) or also what Adrian had mention is also known as expansion valve in laymans term...Search in my profile and you could get my contact number and drop me a line cause its easier to explain as I'm not good in writing....Btw I'm with Eurokars Group located at Sungei Kadut not far from your location but we do not service other makes except our brands... I can only give you my advise but I'll leave the choice of workshop for you to visit / patron.

Rgds,
Td_04

[td_04]

Hi guys, seems to see a lot of useful advice here so I like to ask for advice for my problem with my car aircon too.

My car's aircon will sometimes stopped blowing air out from the air-vents completely. If I have switch my aircon off and then on again sometimes it will start immediately, but sometimes I will have to wait a while and then turn on before it will work again. The cooling is fine, just that it turns off by itself at times.

Any idea what could be wrong here?

Hi Johnson,

It sounds to me like your a/con blower might fail you anytime soon but I may be wrong...I knew that you drive a Bimmer but did not notice whether your aircon system is equip with ACC (Automatic Climate Control) or MCC (Manual) cause this unit may also be the culprit....

Rgds,
Td_04

[pck]

Hi John, td_04, thanks for your advice.

I went to one so-called aircon specialist and the guy told me my compressor 'up the lorry' and said i had to change the entire compressor which will cost $1400! When I said I will think about it, he told me not to 'think too long' as it may lead to more complications which will result in higher repair cost...

My car is 7.5yrs old now and I am really hoping that I don't have to spend too much $$$ on the repair. If the air is still cold, then can i safely say that the compressor is still working?

John, yes the cool air is still coming out when i switch on the 'leg vent'. I will try the Shell station at Serangoo garden. Hopefully they can fix the problem without buring a hole in my wallet. The hot weather is coming and the last thing i need is the aircon stopped working in the middle of the day.

[pck]

Hi Johnson,

It sounds to me like your a/con blower might fail you anytime soon but I may be wrong...I knew that you drive a Bimmer but did not notice whether your aircon system is equip with ACC (Automatic Climate Control) or MCC (Manual) cause this unit may also be the culprit....

Rgds,
Td_04

It's ACC bro...

[td_04]

Hi John, td_04, thanks for your advice.

I went to one so-called aircon specialist and the guy told me my compressor 'up the lorry' and said i had to change the entire compressor which will cost $1400! When I said I will think about it, he told me not to 'think too long' as it may lead to more complications which will result in higher repair cost...

My car is 7.5yrs old now and I am really hoping that I don't have to spend too much $$$ on the repair. If the air is still cold, then can i safely say that the compressor is still working?

Hi Bro,

Since the aircon is cold I dont think the compressor kaput cause worst case scenario it will still blow air but warm air instead...You may try calling up PML for advise but if you want and (I happen to have a former colleauge who is working there and base in Alexandra workshop) Sms or drop me a line on your model and year of manufacture and I'll try to get more info from him regards to your concerns....

Rgds,
Td_04