***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
#51
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
ok i have an EF, stock motor, EG half size radiator w/ SPAL fan, and pusher fan in front of condensor. i recently blew the safety valve on the compressor. the tech told me it was due to not getting sufficient flow to the condensor. my question is would running the stock radiator setup with two puller fans like stock configuration be more sufficient?
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
nice write-up, (2000 civic ex 4door) my wifes compressor went out so im changing that and the accumulator/drier because i heard if you dont change the drier its like changing the oil and not changing the oil filter, also the place i went to recommended the ac expansion device linked below but you know how people always try to up sell you, anyways, should i get the expansion device or is it not worth the $45?
http://www.discountacparts.com/Honda...-60~40198.html
http://www.discountacparts.com/Honda...-60~40198.html
#53
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
yes, if your already changing those other things out, you might as well change the expansion valve too while the system is open.
i dont remember exactly, but i think i got mine at autozone for around $30.
i dont remember exactly, but i think i got mine at autozone for around $30.
#55
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
got a 95 accord after tcompresor seized up and was replaced along with the reciever dryer and charged up a month later started blowing out wark air compressor stays engaged both fans work , hooked up the manifold gauges Low read 30 high read in the 90 tried evacuate vacum and recharge still blowing warm air.
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
The new compressor I got says to flush and vacuum the A/C before installing new parts, any idea how to do that? Also says to check the oil in the compressor?
#57
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
to check oil in the compressor, you take the old compressor off and pour the oil out of it in to a jar. get another jar and pour the exact same amount of NEW oil in to it, then pour that into the new compressor.
i guess that wouldn't really classify as checking it though, more like measuring it so you put the right amount of oil into the new comp. (other than pouring the oil out, i dont know of a way to "check" it)
as far as flushing the system out, i usually take all the ac components out and apart. then i use some denatured alcohol and spray into everything with an air hose until it all comes out.. then i let the parts sit for a few mins just to let all the alcohol dry out.
once you've put everything back together with new seals, you hook up a vacuum pump to it. i think this is covered in the 1st page or one of the other AC threads..
i guess that wouldn't really classify as checking it though, more like measuring it so you put the right amount of oil into the new comp. (other than pouring the oil out, i dont know of a way to "check" it)
as far as flushing the system out, i usually take all the ac components out and apart. then i use some denatured alcohol and spray into everything with an air hose until it all comes out.. then i let the parts sit for a few mins just to let all the alcohol dry out.
once you've put everything back together with new seals, you hook up a vacuum pump to it. i think this is covered in the 1st page or one of the other AC threads..
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
ok so i got everything on, and my old compressor didnt have any oil in it so i put 4oz of pag 100 in the new one, new ac belt and new drier........so i started the car up and it sounded like ****, definitely coming from the new compressor, is this because the A/C belt is too lose? too tight? not enough oil in the compressor? i tightened it to about as tight as i usually do an alternator so it is fairly snug, thanks for any input
#59
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
umm... can you elaborate on the sound its making?? was the system vacuumed? is the system working at all ? does it just sound bad or what??
#60
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
I've determined that there's a problem with my heater valve control cable. I removed it from the heater valve and the heater valve moves smoothly. The cable seems frozen. Whenever I start the car, I can hear a grinding sound coming from behind the dash only when I have the temperature **** turned to cold. I'm assuming that the electronic AC system is trying to push that cable, is unsuccessful and gives up after about a minute. Can anyone help me with replacing that cable? I can't even find it's location in the dash. My Chilton manual describes how to fix it, but assumes you know how and where to tear apart the dash to access it. There are no pictures.
If anyone could provide me with a guide, along with some pictures, that would be great. I'm driving a '99 Civic LX Sedan.
Thanks in advance!
If anyone could provide me with a guide, along with some pictures, that would be great. I'm driving a '99 Civic LX Sedan.
Thanks in advance!
#61
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
ok i have an EF, stock motor, EG half size radiator w/ SPAL fan, and pusher fan in front of condensor. i recently blew the safety valve on the compressor. the tech told me it was due to not getting sufficient flow to the condensor. my question is would running the stock radiator setup with two puller fans like stock configuration be more sufficient?
#62
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Are all Honda Civics "prewired" to have a/c? I am trying to do a retrofit and want to know what I am getting into.
#64
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Can you extrapolate a bit? Believe it or not I have searched and looked at the a/c install for the 5th gen. Starting with in the cabin, do I need a harness that connects to a now empty plug inside the cabin or is the a/c already wired into the button? In the engine bae, what controls the compressor? I saw that there was an empty plug by where the fan goes, but...?
#65
Oh look, I can change this
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Nothing required in the interior. All pre-wired. That 2- or 3-wire connector plugs in to the thermostat. ONLY section required is under-hood. Connector is pretty obvious on the passenger side, towards the front.
#66
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
I have a thread here: https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/honda-civic-dx-c-retrofit-questions-wiring-3046993/
If you would be willing to come over and help me out a bit. Don't want to clutter this very good thread anymore than I have.
Have a picture in the thread of the harness I have to make sure we are on the same page.
Thanks!
If you would be willing to come over and help me out a bit. Don't want to clutter this very good thread anymore than I have.
Have a picture in the thread of the harness I have to make sure we are on the same page.
Thanks!
#67
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Good Read, Well Done.......I have a Acura 07 TL type s with the 3.5. The AC is blowing off at the rear of the ac compressor. I, am hoping the high pressure regulator is stuck open and there is a mechanical high pressure blow off on my compressor or is it the seals or housing on my compressor fubar? I am a heavy equipment mechanic and do some AC work but first time working on a Acura.
#68
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
if the ac is compressor is fine, a vacuum has been pulled and the drier replaced, and correct amount of oil/freon replaced. and the compressor clutch engages but never cycles, and at no speed is the ac cooling, would this indicate a bad expansion valve or evaporator, or would it indicate a problem with a blockage or poor flow with the condenser?
#69
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
^Hook up a manifold gauge set to measure the high and low side pressures with the engine running and A/C on.
#70
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Is it a bad thing to add refrigerant when your condenser fan is not blowing?
I checked my high and low side with a manifold gauge, and they show as being in the yellow range, but my compressor seems to cycle very quickly unless I am at high rpm's. If my temp gets close to overheating because of traffic, etc., then my compressor will cut on and off within a few seconds, so i hope I am not damaging my compressor. Any ideas?
I checked my high and low side with a manifold gauge, and they show as being in the yellow range, but my compressor seems to cycle very quickly unless I am at high rpm's. If my temp gets close to overheating because of traffic, etc., then my compressor will cut on and off within a few seconds, so i hope I am not damaging my compressor. Any ideas?
#71
re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Assuming that i have this problem
"If you observe erratic needle movement, consistent fluttering, wild jumping (generally on the high side) you could have a bad compressor reed valve, or a partially blocked orifice tube or hose. replace the offending component, plus the filter assembly and metering valve, and retest."
Will any refrigerant oil need to be added as well and if so how can you determine how much will be needed? I plan on replacing filter assembly and metering valve. Also what would be the steps to clean or flush orifice tube and hose?
"If you observe erratic needle movement, consistent fluttering, wild jumping (generally on the high side) you could have a bad compressor reed valve, or a partially blocked orifice tube or hose. replace the offending component, plus the filter assembly and metering valve, and retest."
Will any refrigerant oil need to be added as well and if so how can you determine how much will be needed? I plan on replacing filter assembly and metering valve. Also what would be the steps to clean or flush orifice tube and hose?
#72
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Oil should be added to the system in regards to the manufacturers specifications for removing said device/part. In the event that there is not a specification, I add according to what I see. If it leaked I put nearly and ounce in especially if the leak is evident.
Take care not to over oil the system, it will impair the refrigerants ability to do its job. It coats the pipes and insulates the refrigerant from the lines.
Take care not to over oil the system, it will impair the refrigerants ability to do its job. It coats the pipes and insulates the refrigerant from the lines.
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
i this thread.
a/c operation is so simple, yet sooo misunderstood. (i guess it's like every other aspect of a vehicle)
a/c operation is so simple, yet sooo misunderstood. (i guess it's like every other aspect of a vehicle)
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Thermo-Expansion Valve (TXV)
This device controls the flow of refrigerant into the evaporator by sensing the discharge temperature on the evaporator outlet. (Compressor suction line) It has a diaphragm controlled valve and has a remote calibrated sensing bulb connected to this diaphragm via a thermal tube. Some may also have a ballast tube used to create differential pressures to control the valve as well. The cooler the evaporator outlet is, the more it opens, the higher the outlet temperature, the more it shuts.This method of control is purely mechanical, requiring no electronics to control the valve itself.
The flow is backward in the diagram. If the connection size is different you can't hook it up wrong, but if they're identical hooking it up backward will cause it to slam shut under flow.
The extra capillary tube found on some expansion valve is EQUALIZATION tube to CANCEL the pressure differential from evaporator inlet and outlet, not to create.
Also, the warmer it is more it opens, colder it is less it opens.
The temperature of liquid refrigerant in evaporator corresponds to boiling point of refrigerant at low side pressure. When the pipe exiting the evaporator is at exactly the same temperature, it is said that superheat is zero. Superheat is the temperature of refrigerant vapor above the boiling point at the point of exit. For MVAC, it is usually 5-8deg F.
The sensing bulb is filled with R134a and the TXV modulates the incoming liquid refrigerant. When the temperature is the same, there is no pressure differential. A spring is added to add pressure so that it modulates the flow to provide 5-8F superheat.
If there is no superheat, it will cause refrigerant to leave the evaporator. If it's a small amount, the line going back to compressor will become an extension of evaporator and reduce efficiency. If it's a large amount liquid will go back to compressor and cause damage.
TXV systems do not have a suction accumulator because a functioning TXV prevents evaporator from getting more liquid refrigerant than it can evaporate.
Last edited by Dudeliness; 08-20-2012 at 12:13 AM.
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re: ***Air Conditioning - A/C Guide, How it Works, and When it Doesn't***
Take components to A/C shop with a flush machine.
or
Depending on replacement part cost, you may find it cheaper to DIY replace condenser and/or evaporator than monkey with flushing. This is more so for evaporator since replacing evaporator will practically eliminate existing mold/mildew which is hard to remove completely.
Avoid mold regrowth by letting it dry by running the last few minutes of drive on vent without A/C on.
You should install an inline filter if you don't want a compressor failure down the road.
Inside of parallel flow condenser and fin and plate is similar to water treatment settling tank. Debris will settle and do not flush out completely and can get expelled subsequently and cause damage.
If you just put it back together anyways the effect on the compressor is similar to the effect on engine from driving in sand without an air filter.
.