Closed - Car Talk - Nairaland
Nairaland Forum / Nairaland / General / Car Talk / Closed (82689 Views)
5 Sounds That Signal Your Car Needs Auto Repairs Immediately / Thread For Volvo Car Owners/lovers / Its A/C Season Again, Lets Share Problems And Solutions (2) (3) (4)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) ... (22) (Reply) (Go Down)
| Closed by GAZZUZZ(m): 1:10pm On Aug 25, 2016 |
closed 3 Likes |
| Re: Closed by Specialist900(m): 1:15pm On Aug 25, 2016 |
Good one boss. 1 Like |
| Re: Closed by GAZZUZZ(m): 1:57pm On Aug 25, 2016 |
Air conditioning's main principles are Evaporation and Condensation, then Compression and Expansion. To the engineer and physicists they talk of thermodynamics - but we'll explain it in our own way here: Evaporation: You may have noticed that if you rub a little surgical spirits on the back of your hand, then your hand will feel cold. Why is that? It's evaporation. It is because the spirits on the back of your hand start to evaporate. As the spirit evaporates, it takes away heat from the surface of your skin. Condensation: Have you ever noticed when somebody walks in from the cold into a take-away wearing glasses, their glasses steam up? Why is that? It's condensation. The moist air of the take-away cools as it contacts the cold surface of the glasses and the air has less capacity to hold moisture, so it condenses into water on the glasses. Heat of Compression: Have you ever noticed when you pump up a bicycle tyre with a hand pump, that the end of the pump gets hot? This is because the energy that you have put into the air by pumping it has not only compressed it, but has also caused the air molecules to push closer together so giving off heat with the friction. Compression: At some point all gases will eventually become liquid. An example of that would be a can of deodorant - it's liquid inside the can (because you can hear it when you shake it) but is a gas when it comes out and hits your underarm. The pressure inside the can is higher, so the propellant inside is liquid. Cooling by Expansion: Going back to the deodorant, you will notice also how cold it feels that's because the propellant has just expanded in volume quickly. Link: airconcars.com/html/how_it_works.html 7 Likes 2 Shares |
| Re: Closed by GAZZUZZ(m): 2:00pm On Aug 25, 2016 |
Hard tubing and flexible hoses connect all the actual components of the air conditioning in your car. Evaporation and condensation, expansion and compression are the physics of why it works. There are five main components to the whole system, namely the Compressor, Condenser, Receiver-dryer, Expansion valve, and the Evaporator. The fluid that passes around the whole system is the refrigerant. The refrigerant can evaporate at a low temperature, and then condense again at a higher pressure. In the bad old days, R-12 was the refrigerant used in almost all cars. It was widely available, however it was found to be a contributor to the hole in the earth's ozone layer as it was a chlorofluorocarbon (CFC). These refrigerants were discontinued, and all cars after 1996 use a non-CFC fluid called R-134A which is kinder to the environment. So, here is how all the various parts of a car's air conditioning works: Compressor: The compressor is the work horse of the air conditioning system, powered by a drive belt connected to the crankshaft of the engine. When the aircon system is turned on, the compressor pumps refrigerant vapour under high pressure to the condenser. Condenser: The condenser is a device used to change the high-pressure refrigerant vapor to a liquid. It is mounted in front of the engine's radiator, and it looks very similar to a radiator. The vapour is condensed to a liquid because of the high pressure that is driving it in, and this generates a great deal of heat. The heat is then in turn removed from the condenser by air flowing through the condenser on the outside. Receiver: The now liquid refrigerant moves to the receiver-dryer. This is a small reservoir vessel for the liquid refrigerant, and removes any moisture that may have leaked into the refrigerant. Moisture in the system causes havoc, with ice crystals causing blockages and mechanical damage. Expansion Valve: The pressurised refrigerant flows from the receiver-drier to the expansion valve. The valve removes pressure from the liquid refrigerant so that it can expand and become refrigerant vapour in the evaporator. Evaporator: The evaporator is another device that looks similar to a car radiator. It has tubes and fins and is usually mounted inside the passenger compartment behind the fascia above the footwell. As the cold low-pressure refrigerant is passed into the evaporator, it vaporises and absorbs heat from the air in the passenger compartment. The blower fan inside the passenger compartment pushes air over the outside of the evaporator, so cold air is circulated inside the car. On the 'air-side' of the evaporator, the moisture in the air is reduced, and the 'condensate' is collected and drained away. Compressor: The compressor then draws in the low-pressure refrigerant vapour to start another refrigeration cycle. The refrigeration cycle then runs continuously, and is regulated by the setting of the expansion valve. The whole process is reasonably simple when explained like that. All air conditioning systems work on the same principle, even if the exact components used may vary slightly between car manufacturers. Link: airconcars.com/html/how_it_works.html 5 Likes 1 Share |
| Re: Closed by RazaqMB(m): 6:26pm On Aug 25, 2016 |
My nissan xterra   it has gone bad again just as you said  1 Like |
| Re: Closed by chukel(m): 7:53pm On Aug 25, 2016 |
Following 2 Likes |
| Re: Closed by salvo583: 9:49pm On Aug 25, 2016 |
My AC system gets cold iff you're in d front seat. The passenger at the back always complain of heat which leaves me at d mercy of No AC when carry people at the back. What could be the cause. 1 Like |
| Re: Closed by GAZZUZZ(m): 6:02am On Aug 26, 2016 |
RazaqMB: in your case, I'm 100per sure there's a leak in the system, and the compressor has shut down because pressure is below 25psi. 2 ways to attack your problem. 1. Electronic sniffers. These are leak detectors designed to make a beep when a gas leak is detected (I will post pics of the ones I use in the morning) 2. fluorescent dye tracer system for finding leaks. To find refrigerant leaks using the fluorescent tracer system, you first have to install the fluorescent dye into the AC system. The type I use at work has a device that looks like a caulking gun and a hose that connects to the low side fitting. Then you actually push the dye into the low side with the engine running and the compressor engaged. Next you run the air-conditioning system for several minutes to distribute the dye evenly. Then you put on your yellow glasses and examine the system with a fluorescent light. The fluorescent dye shows up easily wearing the yellow glasses. (pics when I get to work) Update: added pics fluorescent dye method 3 Likes
|
| Re: Closed by GAZZUZZ(m): 6:07am On Aug 26, 2016 |
salvo583: problem sounds like a dirty cabin filter. When was the last time you replaced or washed it? (there are washable types) 1 Like
|
| Re: Closed by GAZZUZZ(m): 6:32am On Aug 26, 2016 |
link:slideshare.net/mobile/AboNasserAlYahri/air-conditioning-system-automotive
|
| Re: Closed by salvo583: 7:00am On Aug 26, 2016 |
GAZZUZZ:I haven't changed it before. I guess i have to change it 1 Like |
| Re: Closed by shedyman: 8:04am On Aug 26, 2016 |
When I put of my AC, I hear this funny sound coming up from the dashboard, can any one kindly profer solutions? 1 Like |
| Re: Closed by GAZZUZZ(m): 8:36am On Aug 26, 2016 |
shedyman: hissing sound? Low charge |
| Re: Closed by fortunejum: 8:37am On Aug 26, 2016 |
GAZZUZZ:Am having the same issue, but i was told that my car 1999 toyota camry has no filter. what should i do? |
| Re: Closed by GAZZUZZ(m): 8:54am On Aug 26, 2016 |
fortunejum: correct, meaning air flow is not your issue, since there is nothing restricting it. Look at this pic closely the cabin temp is 10.5 degrees, it went al low as 6.5 when re-filling was complete. What is your cabin temp? 1 Like
|
| Re: Closed by fortunejum: 10:24am On Aug 26, 2016 |
I will ask the technician to check |
| Re: Closed by 9icetoo(m): 1:11am On Aug 27, 2016 |
the issue with mine is that it works intermittently. on cool days and early mornings or late evening, it works but doesn't cool as well as it should. I have changed compressor and replaced a leaking low pressure hose but the problem persists. its an automatic compressor and I'm considering changing it to a manual compressor but not the usual Peugeot compressor. it never works on a hot day. there is gas in the system. I have also replaced condenser. there is power supply to the compressor as the system is fed with 12 volts which the Ac guy verified with a light bulb tester but even with power supply, I don't get any cooling whatsoever on a hot day. the radiator and condenser fans work as well. car is Skoda Octavia with the annoying sanden compressor. any pointers? 1 Like |
| Re: Closed by GAZZUZZ(m): 7:25am On Aug 27, 2016 |
9icetoo: what are the low and high side pressures when a.c is turned on? |
| Re: Closed by connkg(m): 7:54am On Aug 27, 2016 |
Hello Gazzuzz, I hear a gurgling sound sometimes, when A/C is running. Thought it was a rat or struggling snake...from under fascia of front passenger seat. (I usually use "Auto"/pre-set climatic on Honda Accord '02, V6) 1 Like |
| Re: Closed by GAZZUZZ(m): 8:04am On Aug 27, 2016 |
connkg: iv got same sound in my avensis at the moment. It is caused by excessive play of the blower motor, or foreign material touching the blades of the motor |
| Re: Closed by okpeho(m): 11:03am On Aug 27, 2016 |
Hello Gazzuzz, Please, I have this challenge with my Honda Civic automatic (2002) model. The A/C cools and works very well in the morning and afternoon but it does not cool in the night. Sometimes while driving home in the night, it will refuse to work until I arrived at my destination, park and then start the car again, switch on the A/C, then it will start working again. @ Gazzuzz, please what do you think is the problem? Thank you as I await your prompt feedback |
| Re: Closed by 9icetoo(m): 11:38am On Aug 27, 2016 |
GAZZUZZ:the LST time I took it to a tch, it was 35 and 120. not sure of the low side figure now. we had to bleed off some gas to get to 35 on the low side and it started cooling. I left and the intermittent issue resumed 30 minutes into my drive. I will get the figures again today. |
| Re: Closed by GAZZUZZ(m): 12:55pm On Aug 27, 2016 |
okpeho: Very strange problem, it normally happens the other way round. . Location sir? |
| Re: Closed by GAZZUZZ(m): 12:57pm On Aug 27, 2016 |
9icetoo: Compressor is toast. You need a new compressor for sure. Low side should be at least 25psi high side 180-200psi (for most vehicles |
| Re: Closed by okpeho(m): 2:36pm On Aug 27, 2016 |
@ Gazzuzz, Thanks for your swift response sir. Location is Ilasamaja, Mushin sir. |
| Re: Closed by Ozzugworgroup: 5:12pm On Aug 27, 2016 |
Pls...my car goes off after some minutes when my ac is on especially when am abt entering a pothole... |
| Re: Closed by GAZZUZZ(m): 8:22pm On Aug 27, 2016 |
okpeho: Oh good you are in lagos, you can contact me on my signature, and book an appointment, diagnosis will be free. 1 Like |
| Re: Closed by GAZZUZZ(m): 8:23pm On Aug 27, 2016 |
Ozzugworgroup: Introduce your vehicle, and engine specifications. Include any modifications that may have been made. |
| Re: Closed by Teeboy06(m): 8:39pm On Aug 27, 2016 |
I just get Toyota sienna Nigeria used and the a c not chilling at all , just blowing fan and I took it to Ac repairer and refill the gas for me and it was chilling after a week it started blowing ordinary fan again and I took it to the same guy again and he said my evaporator is bad and charge me #40,000 and I smell foul and asked him to leave it.please advice me.thanks 1 Like 1 Share |
| Re: Closed by okpeho(m): 9:05pm On Aug 27, 2016 |
GAZZUZZ: @ Gazzuzz, thank you so much sir for your concern. I will definitely get in touch with you. I appreciate sir. |
| Re: Closed by tegbeyemi01: 9:28pm On Aug 27, 2016 |
@gazzuz i drive a nissan almera 1999. D ac used to work perfectly since i bought it until some days ago, i put on d ac and ut hooks d engine till it goes off.. I noticed if i put it on nd d compressor tries to roll, it makes d engine stop thru stopping d fan belt.. Then i tried to check d gas pipe, pining it with an object to check there was gas there, to my surprise a black watery substance was coming out.. My kazeem says i need a new compressor.. Just want to confirm whats up sir.. |
| Re: Closed by GAZZUZZ(m): 8:07am On Aug 28, 2016 |
tegbeyemi01: Compressor is frozen solid  New compressor Dryer receiver Expansion valve Possible new discharge pipes Preferably new condenser. 1 Like |
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) ... (22) (Reply)
See The Monster Car That Got People Talking / The Cars Mark Zuckerberg, Warren Buffet And Other Billionaires Drive / See How This Abuja Taxi Driver Packaged Himself
(Go Up)
| Sections: politics (1) business autos (1) jobs (1) career education (1) romance computers phones travel sports fashion health religion celebs tv-movies music-radio literature webmasters programming techmarket Links: (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Nairaland - Copyright © 2005 - 2024 Oluwaseun Osewa. All rights reserved. See How To Advertise. 54 |