AC Compressor & other related AC Problems

Transcription

1 AC Compressor & other related AC Problems SANDEN COMPRESSOR: Question: My wife will bring our REVO kina Mang Mario tomorrow for diagnose & repair,sabi sa Santiago City,Isabela Toyota Casa eh compressor daw ang sira and that i dont believe and i need to have a second opinion,binaklas na nga yung AC Compressor, sakali lang if compressor AC nga ang problem at di na maremedyuhan ni Mang Mario.San po ba ako makakabili ng SANDEN AC COMPRESSOR?(address & Tel. # pls. o kaya instructions or guide, galing kasi ng province di kami well verse sa Manila) How much will it cost/price? Turning 5 years old na REVO 2.4L Diesel GLX ko, do you think advisable ba na pabuksan ko na rin yung Dashboard ko para sa cleaning ng AC?am having second thought & mixed emotions here kasi yung sa amin sa Isabela rough road is 1 kms. to & from home, eh baka mag loose mga fittings,bolts or whatever kung sakaling pabubuksan ko yung Dashboard for AC cleaning.what do you think? Answer: SANDEN AIR CONDITIONING CONDITIONING SERVICENTER INCORPORATED ADDRESS 871 Quezon Avenue 1100 Quezon City, Philippines TELEPHONE (632) ; (632) My revo is 4 yrs old na, kung sanden ang hanap mo, ang alam ko, dito sa quezon avenue malapit sa honda show room ang office nila. from edsa, turn right to quezon avenue, bago mag c3, nandun ung sanden. eto pa lang ang nakita kong sanden office dito sa qc. regarding sa pagbalkas ng dashboard, it depends on the worker, dapat may experience na cla magbaklas ng revo para maibabalik nila sa dati. btw, nabaklas ko na rin ung sa akin dahil nag pageneral cleaning na ako ng AC. 19k including charging and installation. Recommended by: Jasper Espino <jasper_espino@yahoo.com> Answer: The a/c compressor on your Revo is probably a DENSO, not a Sanden. I am not sure what model number it is but I am sure of the brand - kakasilip ko lang sa GLX namin, it says DENSO at the back. Diesel ba yung revo mo, or 2 liter? Akin kasi is a 7K-E, baka yun lang ang may DENSO compressor. You need a mirror to look pero baka hindi mo nga kailangan kasi sabi mo yung compressor mo nakakalas na. Anyway, you can get Sanden and Denso compressors straight from the suppliers in CUBAO, Quezon City. Here are the directions: Coming from NORTH SUPERHIGHWAY, take EDSA then turn right at WEST AVE. When you get to the end of West Ave, dapat tatawid ka to get to TIMOG AVE pero hinarang ng inutil na MMDA yung patawid so you have to turn right and make a U-turn to get to TIMOG. When you are on Timog Ave, drive til you get to the Rotonda (may Petron station & Yellow Cab pizza, very good pizza if you're hungry by this time) then turn right, Tomas Morato na yun. Keep going down Tomas Morato until you get to a T-intersection (left & right turn lang). That is E. Rodriguez Jr. and you must turn LEFT to get to Cubao. Keep driving along E. Rodriguez (approx 3 kms) then when you see a small "tunnel" underneath a flyover, SLOW DOWN!!! Malapit ka na! Before you reach the tunnel look to your RIGHT side, you will see a lot of aircon supply stores like MRV, Jovenette, Reynaldo's, etc. Diyan ka pupunta. Show your compressor as a sample. Halos factory price sa kanila. I'm not sure how much ang DENSO na compressor but a typical Sanden SD-508 will cost approx P5,500 to P5,800 sa kanila, versus P10,000 to P15,000 sa casa. REYNALDO'S MARKETING CORPORATION ADDRESS 1978-A E Rodriguez Sr Boulevard 1100 Quezon City, PhilippinesTEL(632) MRV REFRIGERATION AND AIRCONDITIONING PARTS AND SUPPLIES ADDRESS 250 Mayon 1100 Quezon City, Philippines TEL(632)

2 Btw, yung mga aircon supply na yan pati aircon ng bahay at pyesa ng refrigerator meron din sila so kung magkaproblema yung ref mo or yung a/c sa bahay at ayaw mo ng tagang presyo, dyan ka pupunta. Kuha ka ng mga calling cards para matawagan mo sila mula sa Isabela kung magkakaroon ka ng kahit anong a/c-related na problema. As far as your dashboard is concerned, you should not worry too much about it, I have personally removed my dashboard about 5 times in the past 2 years para magpalit ng head unit, maglinis ng mga gauge, magdagdag ng mga switches & wiring. It is just a lightweight plastic cover, the real "dashboard" is made of steel and is welded to the firewall. The Revo dashboard is held in place by 6 metal screws on the lower edge, plus 4 more machine screws inside the glove compartment, plus 2 more machine screws on the ends of the upper surface (covered by plastic caps) for a total of 12 screws. As long as these screws (especially the 6 lower ones) are tight, your dashboard will not rattle. Mine never does. Just make sure you do not OVER TIGHTEN the screws because they can break the plastic material of your dashboard especially when the plastic heats up and expands (if you park under the sun). Just tighten them with hand pressure, do not use a power screwdriver or anything else. You can check every few months kung masikip pa sila, just take a regular philips screwdriver and tighten the screws. Nothing is hidden so madali lang talaga. NOTE: Be careful when you pry off the plastic caps on the upper ends of the dashboard, the plastic can easily be dented PERMANENTLY. Use a broad, flat tool and lagyan mo ng sapin yung ilalim tool para hindi magasgasan o ma-markahan yung dashboard. Kapag nagasgasan yan, hindi mo na mababalik yan so be extra extra extra careful pare. Balitaan nyo nalang ako kung naging maayos yung lakad nyo. Ingat & good luck. Sana nakatulong ito... Recommended by: Steven Yu" stevenedwardyu@yahoo.com COOLING PROBLEM: Question: My car has AC but it is not as cold as the AC in my friend's car Answer: This is usually where I come in and at this point I start asking questions. Many of the answers I would really like to know as they may require specialist knowledge but there are some questions you could ask yourself and make some judgements upon. 1. Bearing in mind the rule of thumb in the section above, how long since it was last charged? If you have owned the car for less than about two years and have no other evidence then look further. 2. Is there enough air coming through the face-level-vents? Turn the blower right up, put the air control to face-level and feel how much air is coming out, insufficient could be the result of blocked pollen/dust filters if you have them or a dislodged piece of air trunking under the dash or a vent control that has stuck or even a blower motor not pulling it's weight. Try pushing the recirculation button (your handbook will show you the logo for this) - if more air comes out of the face-level vents then suspect the pollen filters. 3. The heater may be turned off but is it still working a little and spoiling the AC? Turn off both heater and AC and with the car running on tickover for say ten minutes, the bonnet closed and the blower operating, check that the air from the vents is only at ambient temperature and is not heated. 4. Is the AC compressor actually running at all? Look under the bonnet at where the drive belt is running and get a friend to switch the AC on and off a few times, not too

3 quickly as some systems do not start for several seconds after the switch has been pushed. You should hear a distinct click as the clutch operates and you may then be able to identify which is the compressor, you should then be able to observe that when the AC is turned off the belt turns the pulley only but when it is switched on, the outer plate (which is connected to the compressor internals) turns also. If it does not turn, look first at the fuses - it could be something really simple. Should an AC fuse have blown, before you replace it, check that any electro fan on the radiator is able to turn freely - if it is stiff it may draw excessive current and blow the fuse again. If no fuse has blown probably the most likely scenario is that the gas pressure is so low that the safety switch has operated to prevent the compressor turning and risking damage. Doublecheck that the blower is actually running - if this fails the AC will not run. Early systems using the large black cylindrical Harrison or Frigidaire A6 compressor frequently used a strange three-legged fuse mounted on the front end of the compressor, under adverse conditions this blows to protect the compressor and to ensure that the system is looked at and preferably recharged before the fuse is replaced - this is one fuse that almost certainly means that a recharge is necessary, don't be tempted to just replace the fuse without having the system checked out first. 5. Once you have ascertained that the compressor is running you could try following the path of the thin pipe coming from the bottom of the condenser (the front radiator). This will often go into a type of metal bottle (the receiver/dryer) that will frequently have a small glass eye in the top of it (the sight-glass). Occasionally this sight-glass is independent and is set into a separate small block. Clean the glass and observe it whilst the compressor is running. Is it virtually completely clear? If you can see a continuous stream of bubbles or even what looks like foam then almost certainly the system needs recharging. It is perfectly normal to see a few bubbles each time the compressor starts and stops and if you have the later R134a refrigerant a few bubbles may be seen continuously on a very cold day but otherwise the sight-glass should show only a continuous flow of liquid. The majority of Vauxhalls and Volvos do not have a sight-glass as most of them use a slightly different system, as do some recent Fords. Other Pointers: When it comes to cooling: Expansion valve > kung walang pagbabago sa lamig, di kailangan palitan.unless na kumpleto naman ang karga ng freon at malinis lahat at walang choking sa system. Drier > its a must na palitan everytime na mag-charge ng freon. Pero gawa nga ng sa Pinas nagtitipid tayo. Ok lang na di mo palitan unless nasunog ang compressor mo at marumi na ang langis at pumasok na sa system. Recommended Shop: MANG MARIO 146, fort Santiago, bago bantay QC, near Sinagtala bakery. Telephone: kagagaling ko lang kanina ke mang mario reyes, sa bago bantay,qc, sa likod ng sm west. Turn right ka after SM west (kanto ng Caltex), left ka Bukidnon St (4th corner after Axis Market), right fort santiago st. Dire diretso lang, malapit na yun after the basket ball court sa gitna ng street. pwede ka magtanong sa mga tricyle dirver dun, hanapin mo lang c mang mario reyes, yung gumagawa ng car A/C. Very popular c mang mario. you'll see lots of posts sa mga car forums like tsikot and kotse. marami testimonials sa trabaho nya. Mura kasi sumingil, hindi taga. Imagine, tanggal dash board ng Revo, linis lahat for 900 bucks only! give it a try. me kasabay ako kanina na nagrupo rin natin dito sa revo group. while waiting, pasyal ka muna sm, fater 2 hours tapos na yan. Recommended by : TROC Members KREEKING /KIS-KIS & OTHER ADVENTITIOUS SOUNDS:

4 Question : help naman po, yung sanden compressor meron tunog na parang nagki-kiskisang metal, aka "kis-kis-kis-kis", mukhang sa magnetic clutch yung problem pag nag-engage na yung magnetic clutch eh wala na yung sound, pero once na malamig na eh mag-stop na yung magnetic clutch at ayun na naman yung tunog. so far malamig pa naman yung aircon at walang bubbles sa small glass window sa engine compartment.sa casa eh gusto palitan yung compressor pero ayaw ko kasi mukhang sa magnetic clutch lang and wala daw nabibili na magnetic clutch for sanden... is this true? revo GL diesel 2000 model po yung car. ano recommended shops? Thanks Answer: 1. are u sure hindi maluwag o madumi aircon belt? if magnetic clutch lang talaga problema, baka yung bearing ng clutch assembly. i think there are some aircon shops that sell magnetic clutch assembly only. You just have to look hard. Can't tell exactly where since the last time i did that was many years ago for an old car of mine. i think i bought it in a shop near vito cruz st., makati. 2. okay na yung compressor, yung clutch bearing nga yung sira.. pinalitan lang at nawala na yung maingay na tunog.. pinagawa namin sa Sanden quezon ave...wala talaga ako mapagkatiwalaan na aircon shops..sa denso sana kaso di daw nila kayang ayusin.., eto cost sa Sanden Quezon Ave. and 5% discount Compressor Clutch Bearing (NSK brand and same as original) = 2500 labor = 700 hindi na pinasingaw yung freon, niluwagan lang compressor para matanggal yung magnetic clutch.. medyo nahirapan sila baklasin yung magnetic clutch dahil sa kalawang eto price sa banawe na di ako sure kung meron sila tamang gamit or not.. NSK clutch bearing = 650 labor = 350 here.. talagang mahal, este sobrang mahal talaga sa sanden here... most likely cause ng sira, nabasa sa engine wash yung compressor.. 3. If you look in ur a/c manual, merong service work na magnetic clutch adjustment. maybe ur compressor needs adjustment lang para hindi tumama sa compressor body ung clutch pulley. may makukuha ding parts for sanden, kaya lang mas madalas surplus ang available. try other reputable shops, huwag puro casa kasi madalas tinataga ka lang nila Question: ask ko lang po, kasi nga yung akin GLX lumabas din yung krrrekkk na sounds whenever we switch on the AC into medium cool, tama ka sir, perhaps nabasa rin yung aking compressor kasi lumabas lang ito ng magpa-engine wash ako sa Shell sa amin. Does it also affect coldness? kc yung akin ng lumabas itong kreekkk sounds na ito di na rin gaanong lumalamig. Sabi naman ng mga tropa baka merong pinhole sa evaporator ko. Need your opinion. Answer: saan galing yung krrrekkk sound? sa compressor o sa cabin compartment? kung sa compressor, umiingay lang po ba pag naka-disengage yung magnetic clutch(aircon off)? tapos nawalala yung ingay pag nag-engage (aircon on)?

5 tatlo po ang bearing ng compressor natin sabi sa akin sa sanden quezon ave. and mga 3900php daw kung papalitan lahat.. syempre mura pa rin sa banawe ang parts.. clutch bearing = 2500 bearing inside the compressor = 1200 small bearing = 450 kung pinhole lang butas ng evaporator, yung iba mightybond nilalagay.. mga 6month daw ang tagal.. pero ipa-leak test na ninyo yun evaporator para sure.. or pwede din barado na yung expansion valve or receiver/drier...(not sure about this) kung ipapalinis ninyo yung aircon, mas okay siguro kung i-change oil na rin yung compressor para sigurado.. a brandnew evaporator will cost around 7K a brandnew sanden TRS-105 compressor is between 11K to 15K.. (19K kung sa sanden mismo) My compressor is making a noise - I've been told I need a new compressor They may very well be right but try this first - you may save a lot of money. Turn the AC off and start the car - does it make a noise now? If it does, get someone to switch on the AC whilst you listen carefully - does the noise (A)diminish, (B)stay the same or (C)worsen. If the noise doesn't start until the AC is actually switched on then you probably do need a new compressor although it is worth looking to see if the car has a belt tensioner idler pulley as that might just be the source of the noise. It is also worth saying that my twenty year old Mercedes has a noisy compressor - I've added a little too much oil and I turn the radio up a little but the AC works fine and it doesn't leak. If you have (A) above, you could be lucky; the problem is almost certainly a failed compressor pulley bearing - a fairly common fault. As long as you act quickly you could repair this for the price of a new bearing (between 10 and 40), frequently without even having to recover the refrigerant. If you have (B) above you may also be lucky like in (A) but there is a risk that the main support bearing within the compressor has also been damaged - this would require a rebuilt compressor. If you have (C) you probably do need another compressor AC CLEANING: Question: Kailan po ba kailangan magpa-cleaning ng AUV aircon? Ano ba ginagawa kapag-nagpacleaning? Marami ba binabaklas kapag nagpacleaning? Answer: Toyota recommends every 6 months pero if you want to save, at least once a year ang cleaning dapat. kapag dual aircon yan, isang buong araw ang cleaning. babaklasin ang front evaporator at rear evaporator for pressure washer cleaning. bobombahin din ang lines ng air pressure (nitrogen is better), and the compressor is checked for possible addition of oil. you need to have your aircon cleaned regularly kasi manipis lang ang aluminum ng evaporator kaya madaling mabutas kapag nadikitan ng maraming dumi. Steve, in my case it took me five years na hindi ko pinalinis ung aircon ng revo ko bago bumigay yung evaporator. nung binaklas, may butas due to too much dirt na kumapit na sa evaporator and which cause corrosion. palinis mo na yang aircon mo, malapit na yang bumigay kung hindi mo papalinis. there are many good and dependable shops, just ask around. sa case sa saudi, halos walang traffic jam dun di gaya dito sa metro na kahit saan may traffic jam kaya ang compressor ng sasakyan sa saudi palaging mabilis ang

6 takbo, siyempre hindi hirap ang compressor magpalamig. puwede ka ring magpalinis dun ng aircon, hindi nga lang uso, they rather wait for the aircon to give in bago pagawa at sabay na linis. manipis lang ang evaporator ng revo kaya nga mabilis at malakas magpalamig, kaya madali ring butasin ng kalawang kung hindi regular ang cleaning. I agree with revogsx. in fact, nabasa ko sa ibang thread (kotse or tsikot) na hindi recommended na hindi ipalinis ang aircon because of possible problems sa pag reinstall. I've read from the same thread na car sa saudi hindi talag pinapalinis ang aircon. if i'm not mistaken, it theveed who posted or answered that post. on my case naman, 4 years na revo ko, never ko pa napalinis ang aircon ko pero no problem pa rin. its still cool as before. balak ko sana ipalinis sa kasa (toyota ortigas shaw) 2 years ago pero ang quote sa sa akin is P 7-10K!!! masyado mahal lalo na kung twice a year ang cleaning. depende sa gumagawa, kung minsan mas lalong nasisira yung aircon pag pinalinis dahil napapasukan ng mga dumi at iba pa, yung ibang shops kasi hindi kumpleto ang gamit.. nung nagpalinis ako ng aircon sa liteace ni erpats,after 1 month eh busted compressor, most likely culprit is the improper aircon cleaning..sa revo GL ni erpats, twice na namin napalinis sa toyota north, so far okay pa naman at malamig pa din sya.. Mabusisi pala palinis ng aircon. Two years na nga po hindi nalilinisan sinve nun binili. Saan po ba reliable at maayos magpa-linis po ng aircon ng AUV (Makati Area)? Sigurado po ba maibabalik ng maayos kapag-binaklas nila? sa mga public vehicles lang kelangan yung every 6 months dahil mabilis magdumi.. sa mga private cars depende talaga sa gamit, pwede na siguro at least once every 2 years..ang cost ng cleaning eh usually from 1.5K to 5K including freon and no parts replacement, pero parang sobrang mura ng 1.5K?kung nagpalinis kayo at meron sira at di na pede i- repair, don't buy surplus, it will just cost you more in the long run.. ang cost ng original aircon parts compressor = 12K to 18K evaporator/cooling coil = 7K to 10K usually, evaporator ang unang nasisira at nabubutas sa mga gusto magpalinis ng aircon, sa toyota balintawak north ko pa lang na-try, mga 4K ang labor ang materials, abot ng 5.5K pag palitan expansion valve at drier pwede din kayo palinis sa coolmate denso sa pasong tamo or edsa-quezon ave.. di ko pa na try dito pero at least denso ito.. denso kasi ang aircon ng mga revo gas from GLX to VX, lahat ng diesel po eh sanden.. try calling up toyota casa, they have this 'thunder service', mura ang presyo, alam ko this is toyota's answer to customer requests for a much more competitive service pricing. sa casa din gagawin at although hindi original ang parts, these are duly certified replacement parts by toyota na malaki ang difference sa original price. among the services offered are brakes, clutch and aircon servicing OTHER AC General info and advantages Benefits of air-conditioning are generally accepted an a MUST in the Philippines due to rising temperatures during summer.. What are these benefits? The ability to reduce the in-car temperature to a comfortable level on exceedingly hot days, without having a seventy mile an hour gale buffeting you and being unable to hear the radio or your passengers because of the wind-noise. If you have youngish children you will quickly appreciate the extra quiet in the back aircon seems to almost magically remove the bad temper from most children. As aircon also conditions the air, the ability to remove the moisture from the air coming into the car on really muggy days and to achieve a comfortable atmosphere

7 within the car, perhaps in conjunction with the heater control - the AC button will control the Relative Humidity and the heater if needed will control the temperature leaving you free to enjoy the warmth without being stuffy. Very few cars are not able to utilise this extremely useful facility. The ability to be able to see through the windscreen and all the other glass clearly without a film of mist. The safety aspect of aircon is often overlooked but is extremely important particularly to the mini people carriers which are becoming so popular now. Using the AC button to direct the air to the screen the moisture on the glass will be evaporated very rapidly, long before the heater has had a chance to warm up and will continue this advantage around the side glasses and on to the rear screen. For best effect use the AC button, perhaps in conjunction with the heater in winter and on the fresh air setting (not recirculation). AC is usually extremely good at de-misting and this safety aspect of good all round visibility, even when picking up a crowd of wet noisy kids in winter is one of AC's strong points. The cleaner, fresher air with low Relative Humidity will enhance driver awareness and help prevent drowsiness making your journeys and those of your loved ones safer over long distances as drivers are better able to remain fresh and alert. Being caught in a long traffic jam on a hot day can be purgatory with all the exhaust fumes coming straight into your open windows, particularly if you are dressed for business - wet under the arms and hot under the collar- probably the time when you most wished that you had bought a car with aircon. This is when AC proves it is one of the nicest affordable luxuries. All the air coming into a car with aircon passes through a heat-exchanger, which as it is very cold, quickly becomes dripping with condensation, which collects and drains out under the car. Air entering this heat exchanger will contain dust and pollen grains, but by the time the air has passed through this heat-exchanger (called the evaporator) the vast majority of these pollutants will have been filtered out, trapped by the condensate and dripped back onto the road. It is estimated that approximately 80% of all dust and pollen is trapped in this way on each pass through the evaporator - this helps us all but is a source of particular relief to Hay Fever sufferers or Asthmatics. By allowing all car windows to remain closed, even on the hottest days, the aerodynamics of the car remain at optimum, keeping fuel consumption low and exterior noise to a minimum, increasing safety to the driver and passengers. How does it work? - it's not necessary to know but if you have an enquiring mind read this section The engine drives a compressor that sucks the refrigerant gas in the pipe from the evaporator (that's the heat-exchanger next to the heater) and compresses it to quite a high pressure. This pressure can vary a lot but typically in summer would be around 250 psi. Gas compressed this much heats up considerably. This hot, high-pressure gas leaving the compressor is piped to the front of the car where it is connected to a radiator capable of containing these high pressures. As cool air passes through the radiator it cools the gas sufficiently to turn it into a liquid in exactly the same way that if steam is cooled it turns back into water. So now the refrigerant is in liquid form coming out of the pipe from the bottom of this radiator (still at high pressure remember) and it is piped back towards the evaporator where there is a restriction in the pipe like a pin hole where it is squirted in a fine spray into the evaporator. This high-pressure liquid spray now finds itself in an area of very low pressure (remember this is where we came in - it is the area that the compressor is sucking). It now has the room to expand and turn back into a gas, and it longs to do this, but to turn back into a gas it has to absorb some heat (stretch your mind back to school-days, 'Latent Heat of Vaporisation and all that', is it coming back to you?). It finds the heat necessary to return to a gas by stealing some of the heat from the car's interior - it takes what it needs and leaves you with just a little heat - perhaps five degrees Celsius. Aha - this is just what you want. You feel naturally that the AC is giving off cold, but what is really happening is that it is taking your heat away and leaving you with a lack of heat - which is of course what we call coldness.

8 There are one or two niceties about the system that we don't need to go into here but that basically is the whole system, with the gas being compressed, condensed into liquid and returned to a gas in a continuous cycle. It is the change of state from liquid to gas which achieves the cooling, and if for any reason there is insufficient air passing through the front radiator (the condenser) then the gas will remain as a hot, highpressure gas and will complete the circuit back to the compressor still as a gas and there will be no cooling. It is vitally important that the cooling fans are operating properly, both electro fans and any engine fans, whether directly coupled, viscous coupled or clutch operated. They may be perfectly adequate to keep the engine cool but the extra task of coping with the AC may sort the sheep from the goats. Viscous coupled fans in particular have a finite life and eventually need replacement, as they may no longer be capable of shifting the quantity of air they did in their younger days. An electro fan that may not have had to do any work for six months because the refrigerant has run down and has not been recharged for a time may easily seize up and refuse to work again (particularly common with Ford Scorpios and BMW s). When you press the AC button a sensor checks that there is sufficient refrigerant in the system to not damage the compressor and assuming that there is, it allows 12 volts to flow to an electro-magnetic clutch on the compressor. At this point you can usually hear a distinct click as the clutch is pulled in by the electro-magnet and the compressor starts to turn at the same speed as the belt pulley. Within 15 seconds some cooling can be felt but it may take a minute or so to achieve the lowest temperatures. It is normal for the system to have other sensors to monitor for excessively high pressures (over about 450 psi) and to turn off the compressor to avoid the possibility of damage, and also another to turn on or to increase speed of an electro fan when pressures rise to about 275 psi - this fan will quickly reduce this pressure. The temperature of the evaporator is usually maintained at just over freezing point either by a thermostat or by a switch or a valve that controls the pressure and thence the temperature. This description of a typical AC system is sufficiently accurate for illustration but some slight differences may be obvious in your own vehicle. For example many of the earlier systems used the GM Axial 6 cylinder compressor utilising a strange looking 3 legged fuse, this system does not check for sufficient refrigerant pressure as stated in the paragraph above, but will deliberately blow the fuse if the compressor detects that it would be damaged by an insufficient refrigerant charge - Jaguars were the most frequent users in the UK. But I've got Climate Control Climate Control is a more sophisticated control of temperature to what ever is required by the driver or even the passenger independently. So that the driver may set a required temperature of say, 18º C and the passenger may prefer 21º C. The system will then ensure that both are kept to the temperature they require. However the system tries to anticipate your requirement in other little ways - for example if a sensor detects that the sun is shining, it automatically reduces the settings by two degrees to compensate for the extra warming of the sunshine through the glass. Several sensors monitor other factors and compensate as necessary. Climate Control does sound really the bee's knees and nothing else should be considered. In practice however even the simplest system of AC can work so efficiently that it does make you wonder why anyone should go to the trouble of the complexity of climate control. After a little use it is very easy by adjusting fan speeds and face-level-vent apertures to achieve very acceptable comfort from a very simple system. My own car at present (VW Golf) has a very basic system but takes us down to Laoag City very comfortably indeed. Our previous car, a twenty year old Mercedes, had a slightly more variable system that gave slightly more control, and I suppose that if I had enough money to splash out on a newish Mercedes C Class I think I could get quite spoilt with full Climate Control - but don't misunderstand me, AC is brilliant and full climate control just a little bit more so.

9 If you have a simple AC system you can cheat though. There is no real difficulty emulating some of the characteristics of Climate Control with just plain old AC. If you experience some times when with the AC set on it s minimum setting so that it is giving just a little cold and after a short while the air coming in is too cold for comfort, you could try turning the AC completely off. In all probability, after a couple of minutes, you will get so warm that you need to turn the AC on again. Just pretend you are a Climate Control Module and turn on a tiny amount of heat (with the AC still just turned on believe me it s perfectly alright). This combination of a little heat and a little cold should be just what you need this is all the Climate Control Module is doing for you if you have this. Does the AC use more petrol? The short answer is - yes it does. But in most cases not much it all depends on how the car is used. For example if you get in your car and drive up the motorway for a hundred miles at seventy miles an hour the amount of extra petrol or diesel used to run the AC is negligible. Indeed if you were to turn the AC off and drive instead with a window open to keep cool, you may well find that the increased drag on the car would increase the fuel consumption more than by using the AC button. On the other hand if your car is mostly used for short journeys there may be a penalty to pay in petrol for the comfort of continuous AC. For example you get into a stinking hot car and drive 15 minutes to the supermarket. By the time you get there the car is comfortably cool and you leave it in the full sun for an hour while you do the shop. After the hour the car has returned to its stinking hot status and you have to have the AC on full again for the short journey home. If this is the sort of travelling this car has to do all its life with only short journeys then the fuel consumption is definitely going to deteriorate but after all you get comfort in exchange. For a few minutes each day the compressor is going flat out, taking power from the engine and in addition both the internal blowers and the electric condenser fans are working hard to cool the car down, causing the alternator to work hard to power them and loading the engine further. If this same car is then used for a long journey, after perhaps ten minutes once the internal temperature is reduced comfortably, the AC throttles itself back its done the hard work, now it only has to keep the car cool and now the fuel consumption returns to a much more acceptable level. Similarly if on a hot day you drive along and perhaps note that the fuel consumption on your onboard computer shows 34mpg and you turn on the AC and it immediately drops to 28 mpg it would be easy to assume that you were loosing 6 mpg for the AC. Having read the previous few sentences you can now work out that this simplistic assumption is not in fact correct and that within a few minutes the computer will show a gradual rise to near the point at which it started. Research shows fuel economy on trucks which included the use of AC. This technical evaluation was done at the top speed lorries are able to do with their speed limiters (56mph). At this relatively low speed the effects of an open window are nothing like so serious as at 70 mph, but even so the effect on fuel consumption was an increase of 7% - quite a considerable increase for this moderate speed. With the windows closed and with the AC on, to quote the official report - the consolidated data suggest that air conditioning has a minimal affect on fuel consumption. I've heard that AC is responsible for the hole in the ionosphere Whilst not true there is an element of truth in this story. Up to about twelve years ago only luxury cars had AC in Britain, some Mercedes, BMW's, Jaguars, and the top models of the popular makes, such as the Ford Granada/Scorpio and the Vauxhall Senators. Rolls Royce had a nice system and cars that would otherwise be extremely hot and uncomfortable such as Ferrari, Lamborghini and Porsche had to have AC. Not only cars of course, the top-of-the-range Volvo lorry was fitted as standard with AC over twenty years ago and many farm tractors and most combine-harvesters are also so fitted. They used a system much the same as today but the difference was they used a gas popularly known as Freon.

10 This is a trade name but is properly called R12 and it is this refrigerant which is a CFC and the mis-use of it by the AC technicians of the day that is partly responsible for the problems in the ionosphere. This refrigerant was not only used in AC of course, every domestic refrigerator and freezer all over the world was filled with R12 as was every shop frig or freezer and also the walk-in chillers that butchers have and the huge coldstores that farmers use and the vast freezer warehouses that the processors and the supermarkets use. Food safety legislation over recent decades has forced the use of refrigeration into many areas of life, one has only to notice the large number of chill cabinets in shops for cakes and cheese and drinks and - the list is endless. Additionally there is now a large number of refrigerated lorries on the road where chilled or frozen food must be kept to set temperatures during delivery, take a look when you are next driving on a motorway and first look at the number of Tesco/Asda/Safeway/Sainsbury/etc lorries you see - almost every one is a reefer (refrig), then look at the number of similar artics used by the supplier companies, I'm sure you will be amazed at the extent of refrigeration in transport. Almost every application where refrigeration was needed you would find R12 or another similar refrigerant of the same family of CFC's, the use of it world-wide was huge. Every frig we the general public scrapped would have been broken up by the rag-and-bone man to recover the steel and copper and the R12 allowed to escape. Hindsight is a wonderful thing and if we were able to put the clock back I'm sure that things would have been done differently, but, up until the mid '80s the best knowledge available said that the release of R12 into the atmosphere was safe. In those days, if there was a problem in the system, the refrigerant was released as not only was it thought to be safe, it was relatively cheap and therefore the customer would benefit from a completely new charge of refrigerant with no possible contamination. One cannot blame the local Sainsburys for what was done on their behalf by the technicians of the day; they were doing what was thought right at the time. Now most refrigeration is handled by a different family of gasses, thought to be safer! When a refrigeration or an AC system develops a fault the refrigerant is recovered and recycled - we have moved on. R12 is now only used for the AC in cars built before 1993 but it is not completely dead and buried however - although no longer used in car AC systems it is still widely used by Medicine and also by the Military (among other things it is used to cool the warhead in missiles I believe). How long does the refrigerant last? It varies a lot depending upon a number of factors. Exceptionally I have serviced AC systems on cars that were still working - just - after ten years without being recharged. A more usual time for the first recharge would be around four years. R12 systems will usually last slightly longer than R134a systems as the R12 molecule is larger and the type of oil used with R12 provides a better seal on the compressor shaft I believe. However although R12 systems lose their charge more slowly than R134a systems this is offset by the fact that is more important for R12 systems not have a low charge as if moisture enters the system (as it can with a low charge) this will mix with R12 to create acids within the system which will do no good at all and will start to corrode the system from the inside. A good rule of thumb would be to recharge a new car after no more than four years and then to recharge at three-year intervals. Most problems occur when the system is struggling because it has insufficient gas to do it's job properly, and some of the results can be expensive to put right. It's usually much cheaper to maintain it regularly every three years than to wait for a breakdown and possibly an expensive repair. Particularly do not leave a car with a low charge over the winter months - this is when the air contains most moisture in it and it is likely to enter the system. Get it sorted when you first notice it and you will still have a system next spring - leave it and you take a big risk. I know that it needs occasional recharging but is there anything else that needs doing? Yes very occasionally. The biggest enemy of AC is moisture within the system with the refrigerant. The oil used in AC systems is hygroscopic and will absorb moisture if it

11 gets the chance. Obviously any free moisture floating around in the system will sooner or later get to the place where the cold is produced and will promptly freeze into a chunk of ice thus stopping the AC working. As the evaporator defrosts it will flood the windscreen with moisture and mist up the screen, after a couple of minutes the chunk of ice will melt and the AC will resume working again which will quickly demist the screen and then that blessed bit of moisture will freeze up again and restart the cycle. Every AC system has a container, which has a bag of desiccant in it to absorb any free moisture. Depending on the design of the system this container is either a receiver/dryer or an accumulator. These are intended to be replaced on a regular basis, rather like an oil filter but perhaps not so frequently. If the system should develop a fault it is probably worth replacing this dryer when the fault is cleared but if there is no fault then replacing perhaps each alternate recharge would be prudent - that is, about every six years. This is because the desiccant is gradually absorbing moisture that has entered the system and after a time it reaches the limit of it's capacity - and it is important not to approach too close to that limit. If the drier is really quite old the desiccant can sometime break down and circulate with the refrigerant and eventually clog the expansion valve. This is quite common on the older Jaguars with the long horizontal receiver/drier and manifests itself by the lack of coldness out of the vents but the expansion valve glowing with hoar frost. Some of the common driers are only about 20 but a few specialised ones like some BMW receiver/dryers are more expensive. If you expect about 40 you won't be too far out and you may be happily surprised. A few models produced since about 1998 are incorporating this drier element into the construction of the condenser which has the advantage that when the condenser is replaced after say an accident that the drier is replaced as well (as it ought to be), but does create complications for routine drier replacement in the future - it could be that the manufacturers have used a much larger quantity of desiccant than usual, I do not know about this at present. How do I know when I need a top-up? First let's get this term 'top-up' out of the way. Although this term is often used, I try to avoid using it as in common with any self respecting aircon technician, a top-up is never just a top-up. To operate efficiently an AC system needs a specific quantity of refrigerant. For example a 1990 BMW 525 needs 1,925 grams of R12 whereas a 1999 Rover 200 uses only 560 grams of R134a plus or minus 25 grams. In other words for optimum operation this Rover needs somewhere between 535 grams and 595 grams, no more and no less. This is perfectly typical of modern cars - if the system had only 510 grams or 620 grams it would work slightly less effectively and if the disparity were greater the efficiency would fall even more, indeed if it had too much refrigerant it would quickly get to the point of damage to the compressor. Now to get back to the 'top-up', if the quantity of refrigerant is so crucial, how do I know how much refrigerant to add to the system to bring it to the correct charge? The short answer is I don't. Except in only exceptional cases for short term expedience would I consider just adding refrigerant to an existing system - the correct procedure which is followed in 99.9% of cases is to recover all residual refrigerant, evacuate the system to deep vacuum and recharge with the correct weight of refrigerant. The evacuation to deep vacuum plays an important part in the recharge; it is also the lengthiest part of the recharge procedure. The object of this is to achieve such low pressures within the system that any moisture within the system will boil away at normal temperatures and be drawn away by the vacuum pump. In the absence of any other indications (ask yourself the questions on the page above) a reasonable rule of thumb would be for a first recharge when the car is four years old and thereafter every three years. It is certainly cheaper (and more comfortable) to keep a good charge in the system rather than to repair a system that has been allowed to deteriorate with a depleted system. What is the best way to run my AC?

12 Two examples: Let's imagine that your car has been sitting in the supermarket car park in full sunshine for a couple of hours and is too hot to touch. A reasonable result can be achieved by following this. 1. Open all the doors whilst you load up the car 2. Once in the car, start the engine, run the windows down, set the blowers to maximum, AC on (ensure the Econ button is OFF), any temperature controls to the lowest temperature setting, fresh air (not recirc) and air directed through the Face Level Vents. 3. Once you have blasted the hot air out of the open windows and filled the car with colder air, shut the windows and turn the Recirculation control ON (simply marked as Max on some models). 4. Keep the settings this way until the fabric of the inside of the car has cooled down and then either reduce the blower speed or turn the Recirc control to Fresh Air whichever you choose to do, or perhaps both. 5. Once the inside of the car is really cool, turn the blowers down a little further to suit your comfort and perhaps turn the Face Level Vents upwards to direct the cool air over your head and come down in the rear of the car. Alternatively to use the AC to demist the car the technique is quite different. 1. If the car is already misted up then simply turn on the AC, air directed to screen, blowers to highest speed, fresh air selected and the heat turned to maximum. Many cars simply have a demist button that does all this for you, but try it out as some are only a heated screen, use of the AC will be far quicker. 2. If the weather is warm but the car has misted up, use full heat on the screen together with the AC until it is safe to back the heater off and reduce the blower speed. Continue to use the AC in Fresh Air mode (Recirc OFF) for best demisting. How much would it cost to have Aircon installed into my car? This is a question that I am asked constantly, frequently by . As the answer is not straightforward and what is more, I do not do installations like this, I will go into it a little. If your car does not have AC at all, apart from a little advice, I cannot help. As to the cost the following paragraphs may help a little. Firstly it should be noted that to install AC into a car whilst it is being assembled is a great deal easier and thus cheaper than it is to add it later to a finished car. Having AC fitted later can be a bit of a shock. Let me divide cars into two broad categories: Type 1 Cars built by Japanese manufacturers or by manufacturers heavily influenced by Japan - Examples: Toyota, Mitsubishi etc, and ROVER when it was building cars influenced by Honda, also Range Rovers although probably not under Japanese influence. Type 2 Other cars generally of European origin or design - Examples: BMW, Ford, Vauxhall etc and DAEWOO (uses GM technology) Cars in the first category are relatively simple to retrofit AC as the Japanese tend to install the evaporator under the dashboard in front of the passengers knees, where it is relatively easy to access.

13 Type 2 cars generally have the evaporator mounted underneath or behind the heater matrix right deep behind the dashboard, which means that to access it the whole dashboard with all the wiring, airbags, possibly the steering column needs to come out. This can be a very lengthy and expensive task, possibly up to two days work. The evaporator is not the whole story of course, many cars have the wiring loom for AC installed in all models, whether actually fitted with AC or not. Naturally this simplifies any later retrofit. Also have a look under the bonnet. Is there room for a mechanic to get his hands into the space around the engine like a Honda Civic or is the under-bonnet space crammed with components as are so many cars where a large or powerful engine is shoehorned into a tiny space, necessitating removal of some other components first in order to mount the compressor (about the size of a kilo bag of sugar) and the condenser (a radiator, similar in size and shape to the water radiator and mounted directly in front of it). General rule: the more room under the bonnet, the easier and thus cheaper it will be to retrofit. Type of installation - 4 possibilities 1. Manufacturers kit 2. Approved alternative kit 3. An installation by an AC technician - varies from excellent to very mediocre. Some I have seen are every bit as good as a manufacturers installation but some have been barely adequate. Fortunately some of the mediocre installers eventually go to the wall. 4. A secondhand system.. R12 after October 2000 Now that R12 is now longer available we need to look at what has to be done when it is time to recharge the system. If your car has the earlier refrigerant R12 or Freon (basically prior to 1993) and you feel that it is time to recharge the system let's stop and consider the options. 1. The AC is still working reasonably but it is 3 years since it was last recharged and surely it must need a recharge now 2. The AC is hardly working with little cooling or has stopped completely. Let's cover the first one - number 1. Ignore all my exhortations in the paragraphs above about 3 yearly recharges and hang on to the remainder of the R12 that you have. The alternatives are not as good as R12 so wait until the system is noticeably not cooling as it should and then go on to number 2. Once you get to number 2. there are several options available probably with your AC technician's advice but broadly here is the scenario. If the system has stopped working because of a perhaps a compressor failure, perhaps the best solution is that when the compressor is replaced, also replace the drier and retrofit with the later R134a refrigerant. In many cases a drop in performance may be noticed but should still be acceptable. A few compressors used on early classic cars are unable to use R134a, it is also worth looking at the rest of the rubber hoses as some of the earlier ones are unsuitable for R134a and would need replacing with more modern hoses. Even if the compressor is not being replaced it may be worth considering retrofitting to R134a if the compressor type is capable of handling the higher pressures required - your AC technician will know. You may also consider changing a perfectly performing R12 only compressor for a new compressor which is able to handle R134a, many of which are identical in size and configuration and can fit directly on to the car.

14 In all cases of retrofitting to R134a the oil in the system would need to be changed but the technicalities of the oil type and the extent and type of the change are beyond the scope of this article. The other real alternative is to have the remaining R12 recovered and use one of the 'drop-in' replacement refrigerants for R12 that have been approved for automotive use. Again a replacement drier may be prudent together with the addition of a small amount of a synthetic compressor oil. The performance should in most cases approach that of R12, the loss may not be noticeable. At the moment all the evidence suggests that these replacement refrigerants would need recharging at slightly more frequent intervals than R12, as the risk of compressor damage would appear to be greater as the charge gets low than it was with R12. The details of the law on R12 after January 2001 appear to have been written by someone with little appreciation of the real world out there but maybe someone will revise it with a little common sense. Oh look, there goes another herd of pigs flying past. I feel that a little update might be appropriate on this matter nearly two years after the removal of R12. As at September 2002 we have now treated very many cars that were previously R12 systems. The vast majority of these have been given a refrigerant that is not a mixture of gasses as are some of the drop-in replacements but is basically the latest refrigerant R134a together with additives to ensure that the refrigerant carries the existing lubricant around correctly. In theory at least the system should be slightly less effective than with R12 but I am happy to report that in practice I can see no difference with the performance of the alternative refrigerant