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Old 8th August 2008, 13:33   #1
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Default Air-con woes and Nightmare!

well this is how the story goes, yes its a story, and a long one at that.

i recently got the 40k kms service done and during this service i was very disturbed with less air speed from a/c blower, i could check this out and compare with my friend's accent crdi (54K kms done) and hence knew and felt it clearly. (owing to the summers of Hyderabad it was this june).



so i got the A/C serviced too( this was july), and to my surprise the blower vents were suffering from stuck parking tickets and a ruler i would give the credit to my elder cousin's 4year old it was the very same dark brown stainless steel 15cm ruler.



all of this was removed and cleaned away and then the evaporator was removed, washed, dried and put back, they did this as a part of the ac service and the A/C gas was topped up with approx 250g of gas and 150g of oil if i remember correctly. voila the speed was back to mint.(note the vehicle was 2.5years old exactly then)

i was so damn happy the ac was back and drove home paying a bill of 1700approx.

now after approx a week i drive to srikalahasthi my native place its 40kms from tirupathi.

now this drive gave me a good NIGHTMARE to REMEMBER!
well, i took the road from Hyderabad-nalgonda-narkatpally-piduguralla-addanki-ongloe-vijayawada 4-lane highway-naydupeta-Srikalahasthi.

i started in the afternoon around 1PM, the road from hyderabad to nagonda was fine, 80kmph do-able (depending on traffic ofcourse), then the trouble starts, the roads were visibly very good but all of a sudden there would be a pot hole not less than 1ft deep good enough to wreak my axle! thanks to my MXV8s they saved me and the car, the braking was just simply amazing on those wet roads (it was drizzling), and after that i was forced to maintain 60-70kmph till piduguralla, this is first thing and then,

the night mare starts, after i left narkatpally(close to nalgonda 40kms from it), all of a sudden i notice all the glasses the sides, front, rear, heck even the rvm, all gets fogged JUST OUT OF THE BLUES, all my VISION Is blurred I am stunned for a second and totally confused. With the poor visibility I had I tried pulling over and did so, and got down took a piece of cloth and wiped all the glasses, and got back in the car and to my utter surprise the ac was spitting mist around like a fog machine, I could clearly see this in the cabinís light, and the whole blower area of the was dripping water droplets, I wiped it all. (The AC was on blower speed 1 and ac running all this while), and then just out of curiosity i popped the hood to check out for the ac pipes if they were frozen, when I went to the hood, I stuck my let in a feet deep pot hole wow, just something I need man that was a dirty muddy one and I couldnít help thanking my fate that I dint put the car I this, now I pop the hood and check for the pipes they were just dripping water no ice flakes or any thing unusual on them.

This was one hell of an experience on highways I would never forget, imagine knowing the front or rear road you pull the car just with hazard and head lights and HELL you find a ditch 1 foot deep and you are driving alone in the middle of nowhere, that did give just the kind of jitters to remember or good!

So I get back in the car, turn the ac off and put the blower to full speed and drove till srikalahasthi, I just couldnít dare to turn the ac on even though it was humid, I dint was to be blinded again.

Now I reach srikalahasthi around 10.30pm, I reached this early vowing to the 4lane highway. And I was exhausted and tired by the time I reached I parked and went to bed.

The very next morning I drove to tirupathi, there is a KUN Hyundai service center there, I asked the person to check out my ac, the person promptly attended me, took a test drive with a thermometer, and I told him I had recently serviced the ac and explained all that had been done and what I went through, he says sir we have lesser man power so looking into the problem would take us 3-4 days as it requires removing the entire dash board and checking the thermostat which could have either become weak or for any loose contacts, we currently donít have the scanner here the one available is out of order, how ever he assured me sir you can use the car with the ac but just have the cold knob turned a little towards the warm and this should not happen, or you can just use the blower, nothing else is seriously wrong the car is still highway-drivable.

Man that was really annoying, I just thanked my ill fate, and was kind of happy that at least I can drive the car back to Hyderabad, and drove away from there.

It was after this kkr2k2 came to my place and we went to Chennai and met the fellow Tbhpians there and after about 10 days I came back to Hyderabad.

I took the car again to the Lakshmi Hyundai yesterday, they thoroughly checked my ac out

They kept the car running with ac on for like 2hours in blower speed-1 & cold hot knob to full cold and all the ac managed to do was condense a the water drop lets around the blower but did not spit the mist it previously did, he checked the temperature from the blower and it dropped till 3`C only and the thermostat cutoff was working fine too, he then used both the thermometer and the scanner and they both read the same readings and the graph on the scanner was showing the cut off too, they said sir the ac is perfectly fine, it must be the weather that caused all this menace, it does happen sometimes, you can just use the ac in this season with the cold knob a little away from the full cold, the ac is actually performing at its best. all the evaporator pipes were checked for blocks too.

We could make the temperature a little higher now with some settings of the valves, but you would feel the pinch in the summers and we may not be able to correct it to full cooling like this later.

Then I asked as to why this did not happen for the first 40k kms of the car it was the same way I was running the car and after this service this menace has started, he dint have an ANSWER, and said sir the recent servicing would have cleaned all the dust in the evaporator and would have made the AC OUT-PERFORM!, I was not convinced with this answer, I told him this is not the reason and you are unable to find the problem, I never saw the car spit one drop of water from the blower or condense water around it, and this simply should not happen when the car idles with ac on, he says sir, you saw it for yourself the scanner showing the specs and every thing is just fine in the car.

He says this usually happens to the cars when the weather gets chilling out side, and you say you dint notice the ac pipes freezing either, so there is not point in changing the thermostat either, just use the car this once and make it a point to check out for the ice or ice flakes formations on all the pipes if you find any this time we shall change the thermostat.

With a sighed look and a wasted day I returned home, and I am waiting for my next highway trip to checkout if this problem still persists.

I am clueless as to what actually went wrong, or I am rather unable to get the problem diagnosed.

Should I go to another Hyundai service center or any other good ac mechanic and get this checked or is this normal or JUST WHAT COULD THE PROBLEM BE? HAS ANY ONE FACED THIS BEFORE PLEASE HELP!

Last edited by tsk1979 : 8th August 2008 at 14:08. Reason: No need of separate posts
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Old 8th August 2008, 14:07   #2
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This fog machine effect is normal. When its very very humid due to rainfall, this happens.
The trick is to set the thermostat so that some warm air is mixed with cool air.
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Old 8th August 2008, 14:29   #3
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Quote:
Originally Posted by tsk1979 View Post
This fog machine effect is normal. When its very very humid due to rainfall, this happens.
The trick is to set the thermostat so that some warm air is mixed with cool air.

but his never happened before at all. why now? i have driven this vehicle for the past 2 years in all kinds of weather, and i have put atleast 35k kms myself on this car and why does this happen how?

EDIT: i had put up seperate posts so that i would not bore the readers to read on thats all.
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Old 8th August 2008, 14:36   #4
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This will happen in an AC system when its as good as new.
Moreover you need to have the optimum humidity-temp combination. Within 3-4 months as the cooling coils start getting choked marginally, this effect will go away
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Old 8th August 2008, 15:08   #5
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Cant give you a solution for the problem, but can share an experience. Had a similar problem in my Indica...

Used to spurt out mists of water vapour from the vents... once I think I even saw drops coming out.

This humidifying "feature" started after a A/C service and gas recharge. Stopped after a while...
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Old 8th August 2008, 15:30   #6
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Quote:
Originally Posted by tsk1979 View Post
This will happen in an AC system when its as good as new.
Moreover you need to have the optimum humidity-temp combination. Within 3-4 months as the cooling coils start getting choked marginally, this effect will go away
by coils you mean the evoporator? if so then the ac is actually out performing right now and would take some time for it to get dirty and would soon get back to normal right?

Quote:
Originally Posted by AbhiJ View Post
Cant give you a solution for the problem, but can share an experience. Had a similar problem in my Indica...

Used to spurt out mists of water vapour from the vents... once I think I even saw drops coming out.

This humidifying "feature" started after a A/C service and gas recharge. Stopped after a while...

okay i have to give it time any way as suggested by the HASS so i think i need to wait and watch, will do that.


and did any one else here experience similar problem?
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Old 8th August 2008, 15:47   #7
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Yup, after some time it will get back to normal. I have noticed this mist in all our Tata cars.
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Old 9th August 2008, 10:57   #8
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Hi

I think this is most commonly seen in the aircrafts these days specially which take off from Mumbai (humid waether)

Amit
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Old 9th August 2008, 12:39   #9
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hi rider60,

i don't think there is anything wrong with your air conditioning system. on the contrary it is performing as it should. your first issue was with the windows
frosting on the outside. to understand that phenomena think of a chilled beer being poured in a glass. the glass frosts on the outside, right? why? because the chilled beer inside the glass makes its temperature drop and this causes condensation on the glass. same thing happened in your car. the insides were chilled and the warm, humid weather outside caused condensation on the glass surface due the temperature difference. condensation happens all the time when you run the air conditioner. every air conditioning unit has a water outlet pipe to dispose of all the condensation caused due to the contact between air and the chilled cooling coil. start your air conditioner and look below the car, you will see a steady flow of water droplets.

as for the mist blowing from the a/c vents, same reason holds true. ever been to a cold hill station, when you blow air from your mouth and if its really cold then it will give you the same effect. reason? warm, moist air from your body comes in contact with the cold and dry outside air and cools downs. this causes the water vapor content to convert into miniature droplets of water which we see as mist. same thing happened in your car. when you opened the door to get out of the car, the warm, moist air entered your cabin and that came in contact with the cold air from the a/c vents to give the mist effect. had you closed the doors and kept the a/c running, it would have disappeared in less than a minute.

i don't know if have helped you understand or confused you even more, but be assured that your air conditioning system is not at fault,
its just mother nature with her bag of tricks..

cheers
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Old 9th August 2008, 14:12   #10
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my replies are in bold in the following quote.

Quote:
Originally Posted by gotzuk View Post
hi rider60,

i don't think there is anything wrong with your air conditioning system. on the contrary it is performing as it should. your first issue was with the windows
frosting on the outside. to understand that phenomena think of a chilled beer being poured in a glass. the glass frosts on the outside, right? why? because the chilled beer inside the glass makes its temperature drop and this causes condensation on the glass. same thing happened in your car. the insides were chilled and the warm, humid weather outside caused condensation on the glass surface due the temperature difference. condensation happens all the time when you run the air conditioner. every air conditioning unit has a water outlet pipe to dispose of all the condensation caused due to the contact between air and the chilled cooling coil. start your air conditioner and look below the car, you will see a steady flow of water droplets.

okay this theory is just fine i agree with, it was not only from the outside also inside that this mist formed up remember this never happened for the first 40k kms of the car.

as for the mist blowing from the a/c vents, same reason holds true. ever been to a cold hill station, when you blow air from your mouth and if its really cold then it will give you the same effect. reason? warm, moist air from your body comes in contact with the cold and dry outside air and cools downs. this causes the water vapor content to convert into miniature droplets of water which we see as mist. same thing happened in your car. when you opened the door to get out of the car, the warm, moist air entered your cabin and that came in contact with the cold air from the a/c vents to give the mist effect. had you closed the doors and kept the a/c running, it would have disappeared in less than a minute.

now as a result of this mist the effect explained above took place, what i really want to know is why the hell is the water dripping from the blowers, why is the mist being spit like crazy, only after the last A/C service. like i said above i have been using the same settings for the past 2.5 years and have done 40k kms and this never surfaced before, i have traveled in all kinds of weather and never did this happen once, why now why now, did the guy mess up something while servicing?


thats what i strongly suspect atleast from my point of view? i mean did they remove any packings they are not suppose to, or the has the thermostat become weak or this happens as the A/C and car start aging?

the thing driving me nuts is after the service the ac is suppose to perform to its best and not cause problems like this that didnot exist before, and even after two days at two different HASS they failed to give me a proper technical explanation that is they could not diagnose the problem atleast according to me they couldnt, because this never happened for the first 40k kms, and neither i nor did they notice this in any of the new cars. and just said this is the weather, and it happens at times. which is too hard for me to digest. hope its clear now.


i don't know if have helped you understand or confused you even more, but be assured that your air conditioning system is not at fault,
its just mother nature with her bag of tricks..

cheers

Last edited by rider60 : 9th August 2008 at 14:22.
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Old 9th August 2008, 15:11   #11
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"Hyderabad-nalgonda-narkatpally-piduguralla-addanki-ongloe-vijayawada 4-lane highway-naydupeta-Srikalahasthi" ??

I use this route to Nellore very often. You need to be very careful on this route. The road is very bad these days and not suggested for Cars. SUVs are better on this route. and always stay below 80kmph.
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Old 9th August 2008, 16:30   #12
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Happend once while driving back on the First of January 2004 in a friends car filled with drunk friends.
Was around Patancheru when the car car fully misted up and gave me a scare.
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Old 9th August 2008, 18:51   #13
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Looks like your evaporator is forming frost.To check this see if the airflow reduces when the mist phenomenon you mentioned occurs.If yes your expansion valve is not functioning properly.This can occur while cleaning of the AC evaporator.

There are 2 temps concerned with the manual HVAC,the evaporator temp and the air temp close to the evaporator.The Evaporator temp must be at 0-1 C to prevent freezing of the evaporator and is controlled by the expansion valve by controlling the flow of refrigerant.The air temp is controlled by the thermostat and is set between 3-6C.

Even if your thermostat fails to cut off the compressor the evaporator core will never freeze because of the above arrangement.

Last edited by merve_extreme : 9th August 2008 at 18:53.
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Old 9th August 2008, 20:09   #14
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Quote:
Originally Posted by merve_extreme View Post
Looks like your evaporator is forming frost.To check this see if the airflow reduces when the mist phenomenon you mentioned occurs.If yes your expansion valve is not functioning properly.This can occur while cleaning of the AC evaporator.

There are 2 temps concerned with the manual HVAC,the evaporator temp and the air temp close to the evaporator.The Evaporator temp must be at 0-1 C to prevent freezing of the evaporator and is controlled by the expansion valve by controlling the flow of refrigerant.The air temp is controlled by the thermostat and is set between 3-6C.

Even if your thermostat fails to cut off the compressor the evaporator core will never freeze because of the above arrangement.

now finally finally i have an explanation i can buy, thanks a TON for sharing this info.

now i remember the mechanic at lakshmi hyundai mentioning the valve settings, he said the cooling can be lowered now by doing the valve settings but it might hurt in the summers and it just might not be possible to get the cooling back to normal, and that would hurt later on. i dint pay alot i attention to that part at that time as he was suggestion setting the cold hot air knob settings strongly.

now is it so that this problem can be solved by replacing that valve or should i go by the mechanic's recommendation and set my cold hot knob to a little on the hotter side this season and set it in full cool mode in the summer? can this problem we solved like this or is changing that valve is a good thing or what is the best solution to the problem?

and would using the ac like the mechanic suggested cause problems in the long run?

now that i know the problem i am totally clue less about the solution. PLEASE HELP!



EDIT: also since i have a highway trip soon so let me give it some time as well like the people above suggested but i would still like the answer for the question just above, thanks alot in advance for all the help!

Last edited by rider60 : 9th August 2008 at 20:20.
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Old 10th August 2008, 00:33   #15
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Quote:
Originally Posted by rider60 View Post

now i remember the mechanic at lakshmi hyundai mentioning the valve settings, he said the cooling can be lowered now by doing the valve settings but it might hurt in the summers and it just might not be possible to get the cooling back to normal, and that would hurt later on. i dint pay alot i attention to that part at that time as he was suggestion setting the cold hot air knob settings strongly.
The expansion valve is a precision component,manually adjusting it will be extremely difficult and not worth the effort.

Quote:
now is it so that this problem can be solved by replacing that valve or should i go by the mechanic's recommendation and set my cold hot knob to a little on the hotter side this season and set it in full cool mode in the summer? can this problem we solved like this or is changing that valve is a good thing or what is the best solution to the problem?
Now generally the heater core is in front(towards the vent side) of the evaporator,so there is no way that changing the temperature setting is going to solve the problem of the evaporator freezing due to the malfunctioning expansion valve,changing the expansion valve is the only and proper solution.It will involve removing and refitting the AC piping and hence a refrigerant recharge.

Last edited by merve_extreme : 10th August 2008 at 00:36.
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