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Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

We're back for 2014 2015 2016 2017 2018 2019, sweaty goons.



AC repair is something that shouldn't be attempted unless you are willing to learn how to do it properly. Incorrect repairs and maintenance very often end up costing far more to repair later than you've saved by attempting to bodge it up yourself. No matter what the "recharge kits" you find at the parts store say on them, no.....it's not that easy. If you are lucky it just might work, but it's still the wrong way to go and presents unneeded risks ranging from simply wasting money to bodily injury.



Still with me? OK, then this is the thread for you. Because we're gonna do this the right way with fairly inexpensive tools you can buy or borrow from a parts store, rather than with a $7500+ machine like they do at an actual shop.

I'm going to break this down into a few posts to cover various topics/scenarios. It's all going to be really general, so don't sperg at me about your exceptions.



For now, let's start by covering some basic terminology:

Refrigerant - This is what's in your AC system that makes it cold. No, it's not Freon (probably). Just call it refrigerant unless you know what it specifically is.

R-12: This is a great refrigerant but was phased out of new vehicle production in the '90s because it's not so good for the atmosphere. It is still available as new old stock or recycled, but it is illegal to produce any new R-12. You need an EPA 609 certification to service an R-12 system or buy quantities of less than 30 lbs. Fortunately, it's an open book online test that only costs $30 or so. http://epatest.com/

Freon - The DuPont registered trade name for R-12

R134a - This is probably what you have in your car. Only recently have some other alternatives come to market in a vehicle from the factory.

Condenser - This is the radiator-looking thing that's likely to be in front of your engine's radiator.



Evaporator - This also looks like a small radiator and is nearly always buried somewhere completely goddamn inaccessible. It has to be in the stream of air going through your cabin comfort air system, so it usually ends up in a box under the dash along with the heater core. If you're lucky it might be accessible under the hood.



Compressor - One of those things your serpentine belt turns in front of your motor. Most have a magnetic clutch so that when it's not on the pulley around the outside can still spin but the compressor itself doesn't move. Newer models have internal mechanisms to vary their displacement for greater efficiency.



Dryer (receiver/dryer) or accumulator - These are different things for different types of systems, but the important part is that you'll be replacing them any time you've opened the system to the atmosphere. They have a one-shot-use desiccant pack in them to get any remaining water out of the system after it's been opened. Water turns refrigerant acidic which will eat the system from the inside out.



Expansion valve or TXV - This is a venturi and/or nozzle that liquid refrigerant flows through to be atomized on it's way into the evaporator. This is where the physics come in. If you rapidly decompress pretty much anything it will get cold. Find something that is particularly good at getting cold when it changes phases like that and we call it a refrigerant. This works with all kinds of stuff including ammonia and propane. In fact, both of those are still in service today as refrigerants.



Capillary tube - Like a TXV but for a different type of system. The type that would have an accumulator. These systems are cheap and lovely and what you are likely to find in your car unless you spent some bucks on it.



Most importantly: THIS poo poo CAN BE DANGEROUS



DO NOT start poking around or unbolting things unless you are positive you understand what you are doing. Refrigerant is under pressures up to 400 PSI in vehicle applications and can be even higher during specific types of failures. Venting this refrigerant into your face or hands WILL BURN YOU. As in, instant frost bite, flesh turning black in hours kinda poo poo. Don't be stupid. Know what you are doing, wear safety glasses, long sleeves, and gloves among other appropriate protective equipment.

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Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

BASIC RECHARGE

First we need to figure out if your shitbox a candidate for recharging. If the AC is kinda working but not very cold and you can hear the compressor clicking on and off a lot it probably is. This is assuming that everything else is working like your cabin fan. The other criteria here is that you don't actually have a leak. So if it's not more than 5 years old or has been charged in the last 5 years you really shouldn't be charging it: you should be finding the leak and fixing it first. The rubber hoses in the system are called "barrier hoses". Neither them nor the seals between components are completely refrigerant tight, so it is normal to lose refrigerant over the years. Most vehicles I've dealt with that are in proper working order haven't lost enough refrigerant to cause any cooling related issues until pretty close to 10 years on the road. Some are worse than others, like things with rear air conditioning (more barrier hose).

Now to verify all is well and you are just low on refrigerant. You need to know what's in there. It's going to be R-12 or R-134a. Then you need to get a manifold gauge set appropriate for that refrigerant. If it's R-134a you're in luck.



Now you need to find the high and low side fittings. These are usually somewhere obvious and often close together, but that's not always the case. R134a fittings look like quick disconnects when the cap it off. R-12 fittings look like a big tire valve when the cap it off. In either case the caps simply unscrew (the inside of the 134a fittings are threaded for the cap - this thread is not used for service). You should make sure they have good seals in them, are clean, and replace them when you are done.



Now make sure the car is off and the valves on each side of the manifold gauge set are CLOSED. Put your drat leather gloves on. And eye protection. Seriously. Hook up the blue line (with a black stripe if it's a proper R-134a set) to the low port. It won't fit on the high side. Then connect the red line to the high side. The just push down and click in place. You shouldn't be able to pull them back off unless you pull up on the collar of the fitting at the end of your gauge set hose.

If you are doing this on an R-12 you'll need to do the same thing, but you have the screw the fittings on and you CAN screw up high and low (well, I suppose you can do this with R134a as well by jamming the high on the low port - it will spit some refrigerant at you). High is typically going to be by the receiver dryer, and low....somewhere. Sometimes even right off of the compressor. Here's where Porsche put them on the 944s for exactly a year and a half (85.5 and 86). After that the low side went to the compressor which is accessed from underneath and requires a 90 degree fitting:



Now that you're hooked up with the car off you have the pressure on the high and low sides of the system flowing up the hoses past the gauges and to the closed valves. This means there is no reason to mess with the valves at this point to get a reading: you are already direct to the gauges. If all is well you should see some sort of pressure. This is called the static pressure.

So what should it be? That depends on how warm it is outside.

Let's say is 90 degrees, so we assume your car and the refrigerant is also 90 degrees:



It's right on the gauge. Look at the R134a temperature line and see what the equates to in pressure. It's that simple.

Now there are three things that you may find:

- It's lower than that pressure: This means you have only gas phase refrigerant in the system, meaning there is almost nothing in there.
- It's at the correct pressure: You have some amount of liquid refrigerant in the system. It could be a thimbleful, it could be a tanker truck full. That's just how physics works. No matter how much or how little of a liquid you have it's vapor pressure is constant at a given temperature.
- It's too high: that's bad. You have contamination in the system. Just stop here, you're not recharging it. You have repairs to do.

One other possibility is that you may have one gauge different that the other. If the car hasn't been off/AC off for at least an hour I wouldn't sweat this one, but I would wait it out and try again to be sure. If it's been off overnight and you have different pressures you likely have an obstruction in the system and not only shouldn't you be charging it, you shouldn't be using it at all until you repair it.

So let's assume this has all worked out: you have a low or correct pressure reading on both the high and low side, plus the other criteria previously discussed. This makes it look like an even better chance you can get away with just charging it. On to running pressures. Make sure the hoses aren't going to get tangled up in any moving parts. Make sure you haven't left tools and poo poo in the engine bay. Start the car. AC on full blast, recirculate if you have it (or "MAX AC" on more Fords), windows up and all that. Close the thing up and let it run. We want to let the AC draw as much moisture as possible from the cabin so the evaporator doesn't freeze while we're charging.

Now go back to the gauges. What you should be seeing is the low side going down in pressure as the high side goes up. Then you'll hear your compressor click off and both gauges will swing back to near the static reading. Then it will click back on an repeat this cycle. That's called short cycling.



If your static reading was below 60 or 70, this may not even happen as the "low pressure cut off" switch will probably never even turn on the compressor.

Either way, it's time to put in a bit of refrigerant and see what happens.

Get a can of R-134a. No leak stopper poo poo, just pure R-134a. Get at least one can with dye in it if you see it on the shelf. They don't all need dye. You also need an R-134a "can tap"/refrigerant valve. They're cheap.



When it is screwed all the way in, it will be closed, BUT it has a pin sticking down that is used to break the seal on the can, so you need to OPEN the valve almost all of the way. You do NOT want this pin getting anywhere close to that can seal right now.

Connect your refrigerant valve to the service line (yellow hose) of your manifold gauge set.

Screw the can of refrigerant onto the valve. At this point, the valve you are screwing the can on should be open, and both valves on your manifold gauges should still be closed.

Once everything is all set, CLOSE the valve you put on the can. All the way. You will feel some resistance, and you will hear it hiss. Once itís been closed all the way, the seal is all the way punctured, and you can re-open that valve all the way.

Side note for R-12. They have no threading on the cans. So you get you bust a hole in the side with one of this style can tap:



Some have valves, some don't. Mine doesn't but an R134a valve fits on it so that's what I use. In this scenario you hook that whole contraption up to the service line, put your $35 can of ozone-annihilator in the jaws of the tap and crank it closed swiftly and firmly so the can is punctured and sealed without losing any.

Now back to the generic instructions.

At this point, your service line is charged from the can, your high and low lines are charged from your system, and the only thing between the two are the valves on your manifold gauge.

Now SLOWLY open the low side manifold gauge valve. Youíll see the pressure shoot up to 80 something, the compressor will kick on, it will get dragged back down, it will happen again, etc. Let it go SLOWLY (valve barely open) for 30 seconds or so. Now close the valve. CAN UP THE WHOLE TIME. NEVER INVERTED OR ON IT'S SIDE. Yes, there are times when that is appropriate, but for a basic recharge it's not. If you invert the can you are going to dump liquid refrigerant into the lines and into the low side of the compressor (remember that second post? It's not supposed to be liquid there!). Liquids don't compress. This makes bad things happen. It's called slugging the compressor. If you slug it real good, especially if it's a Sanden, you'll have some pictures for the Horrible Mechanical Failures thread.

What do you hear? Probably still a compressor that is short cycling (or finally doing something), but itís cycling longer now. Open up the low side valve a little bit again. Let in some more. Slowly. I like to stop every 20 or 30 seconds and just let it go for 30 seconds or so at this point in the process. If you donít, you might freeze your evaporator.

If you started with no compressor engagement and the low side is 80-90 (might need to shake the can) and it still won't turn on, just stop. You have a repair issue.

So if all is going well so far, keep adding. Here's a chart to give you a basic idea of what you are shooting for:



Eventually the compressor will stop short cycling. But keep going until you get the required pressures but not over. Too little is always better than too much.

Some things that will be going on here: the can is gonna get cold. The head pressure of the refrigerant will drop because of this, so it will exit the can slower. Also, you may freeze your evaporator if the humidity is high, especially with accumulator systems. If that happens the compressor is just going to shut down due to low pressure on the low side. No big deal, just shut everything down and wait for it to thaw out. To avoid that, slow down and make sure everything is closed up in the car. Once you have a sufficient charge it won't happen.

You might even need more than one can. If you do, just close the manifold gauge, close the refrigerant valve, remove the refrigerant can and valve from the service hose, CAREFULLY open the refrigerant valve to release the residual pressure, and follow the original procedure for attaching a can of refrigerant.

Leather gloves and eye protection for all of this.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

Reserved

Krakkles
May 5, 2003

like and subscribe for more passive-aggressive roadway bullshit adventure in Chigcao

... oh, you do.

e:

Applebees Appetizer
Jan 23, 2006



Ok, perfect timing....Took my car into a local a/c specialist that does great work. My car (2012 xB) was taking an abnormally long time for the a/c to blow cold after it sat overnight. They checked it out and guess what....It needed FREON lol, but it hasn't completely solved the problem. It made a small difference in the time it takes to cool off, but it still takes at least five minutes before it blows cold air. So I'm assuming they saw it was low and figured that was the problem and did no other testing? What else could it possibly be? I really don't want to drop it off again to them but i guess i'm gonna have to to get to the bottom of it.

IOwnCalculus
Apr 2, 2003





Applebees Appetizer posted:

Ok, perfect timing....Took my car into a local a/c specialist that does great work. My car (2012 xB) was taking an abnormally long time for the a/c to blow cold after it sat overnight. They checked it out and guess what....It needed FREON lol, but it hasn't completely solved the problem. It made a small difference in the time it takes to cool off, but it still takes at least five minutes before it blows cold air. So I'm assuming they saw it was low and figured that was the problem and did no other testing? What else could it possibly be? I really don't want to drop it off again to them but i guess i'm gonna have to to get to the bottom of it.

Systems very, very rarely just "run low", and overcharging can be as bad as undercharging. Proper fix would involve actually getting some gauges on it, doing some leak investigation, and probably performing a vacuum / recharge to verify that it's actually at the right charge level before going much further.

Applebees Appetizer
Jan 23, 2006



I'm assuming that's what they did. And because the car had been running for awhile already it was probably blowing cold right away. The problem is when it sits for any length of time.

[e] I forgot to mention one of the valves was leaking so that's why it was low. They ran dye through the system and found the leak, fixed it and filled it up.

Applebees Appetizer fucked around with this message at 23:21 on Apr 25, 2019

meatpimp
May 15, 2004

Psst -- Wanna buy

EVERYWHERE
some high-quality thread's DESTROYED!



Hi thread. It's been over 2 years since I checked the air on the Escalade with the dual system. The air is working fine, but I think it's time to check the pressures. From what was said in the previous thread last time I brought it up, the lines going all the way to the back allow for some leakage over time?

Thelonious
Jul 15, 2005



I'd call it good if everything seems to be working fine. Throwing gauges on without good reason is a good way to waste a small bit of refrigerant or introduce contaminants needlessly.

But I'm just a dumb residential HVAC monkey who can get a pretty accurate idea of system performance just by checking some assorted temperature readings. Probably not as simple on a vehicle.

meatpimp
May 15, 2004

Psst -- Wanna buy

EVERYWHERE
some high-quality thread's DESTROYED!



Thelonious posted:

I'd call it good if everything seems to be working fine. Throwing gauges on without good reason is a good way to waste a small bit of refrigerant or introduce contaminants needlessly.

But I'm just a dumb residential HVAC monkey who can get a pretty accurate idea of system performance just by checking some assorted temperature readings. Probably not as simple on a vehicle.

Is it something you can talk me through on my home system? It's an almost 20 year old Trane A/C unit that I'm hoping to get one more year out of. I last had it checked about 4 years ago. I just cross my fingers every time it runs.

RIP Paul Walker
Feb 26, 2004



Put a thermometer in the vent when the AC is blowing.

I like this style because no batteries is nice: https://www.amazon.com/Rubbermaid-C...=gateway&sr=8-9

STR
May 12, 2006

I thought I was a nice jester


meatpimp posted:

From what was said in the previous thread last time I brought it up, the lines going all the way to the back allow for some leakage over time?

That's true for any flexible hoses for refrigerant. Your Escalade will leak more simply because it has more hose involved than most cars. Modern barrier hoses help (and I think most, if not all, R134a systems use it at least on the high side), but they still leak a little over time.

Something about the small molecules of R-134a... it's over my pay grade.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!



R-134a is always at pressure, and any pressurized system, except maybe a full-welded one will leak a wee bit over time, especially with a gas.

spankmeister
Jun 15, 2008








Slippery Tilde

If want do DIY a compressor replacement, how do I figure out how much oil to put in? I'm getting conflicting information on the internets.

STR
May 12, 2006

I thought I was a nice jester


Did the old compressor lock up?

If so, you need the complete system oil capacity, since you'll be flushing all of the lines and replacing the condenser and evaporator. If you're replacing the compressor because, say, the clutch went out, or a seal on it went out, you should be able to look up how much oil you need for just a compressor replacement online (Autozone's website probably has the info).

New and reman compressors usually ship with enough oil for the complete system. You have to dump it out into a measuring cup and pour the right amount back in if you're not shotgunning the entire system.

spankmeister
Jun 15, 2008








Slippery Tilde

STR posted:

Did the old compressor lock up?

If so, you need the complete system oil capacity, since you'll be flushing all of the lines and replacing the condenser and evaporator. If you're replacing the compressor because, say, the clutch went out, or a seal on it went out, you should be able to look up how much oil you need for just a compressor replacement online (Autozone's website probably has the info).

New and reman compressors usually ship with enough oil for the complete system. You have to dump it out into a measuring cup and pour the right amount back in if you're not shotgunning the entire system.

Thanks!
Yeqh just the clutch is bad but it's one where you can't replace the clutch and magnet.

e: do I need to add the amount for the dryer which I will be replacing as well obviously or is that factored in/negligible?

STR
May 12, 2006

I thought I was a nice jester


It may or may not be a decent amount of oil.

Got a or kitchen scale that can measure down to 0.1oz? Get 2 identical containers of some kind, place one on the scale, zero the scale, pour the oil out of the dryer into the container, note the weight. Swap the other container over, make sure the scale is reading 0 (if not, zero it again), and pour enough fresh oil into it to make it match. Add that weight to the "compressor replacement" oil capacity.

Or get 2 identical glasses, put em side by side, empty the dryer into one, pour fresh oil into the other, get them to match. Again, include the amount of oil as if the compressor is getting replaced.

spankmeister
Jun 15, 2008








Slippery Tilde

Much obliged.

Adiabatic
Nov 18, 2007

What have you assholes done now?


Hello Motronic I want you to know this is the best thread.

IOwnCalculus
Apr 2, 2003





With the new compressor you'll probably want to drain it of any new oil in it and measure that back into it. The new Denso that I put on my who few years ago for the same reason had way more oil in it than necessary for a not-dry system.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

IOwnCalculus posted:

With the new compressor you'll probably want to drain it of any new oil in it and measure that back into it. The new Denso that I put on my who few years ago for the same reason had way more oil in it than necessary for a not-dry system.

In fact in this case I'd probably just remove the old compressor, drain it to measure what's in there, drain the new one and replace with how much came out of the old one.

nitsuga
Dec 31, 2006

It's the only way to live.

Is there any harm in leaving an A/C system undercharged? Iím not sure I have a leak, but I think I might. Iím trying to figure out how much I should or shouldnít prioritize fixing that.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

nitsuga posted:

Is there any harm in leaving an A/C system undercharged? Iím not sure I have a leak, but I think I might. Iím trying to figure out how much I should or shouldnít prioritize fixing that.

If it has any pressure in it it's at least not completely open and getting water in it, so it's not too bad. If it's still running it's probably running like poo poo and icing up. That's more annoying than damaging.

nitsuga
Dec 31, 2006

It's the only way to live.

Motronic posted:

If it has any pressure in it it's at least not completely open and getting water in it, so it's not too bad. If it's still running it's probably running like poo poo and icing up. That's more annoying than damaging.

Thanks! I might call around a bit to see what it would cost to get diagnosed. This and the last thread have convinced me A/C is not my gig. Good to learn from, but like zero interest in opening it up.

STR
May 12, 2006

I thought I was a nice jester


A friend has a car that's been parked for almost 3 years. I know I'm already an idiot for considering this car just due to how long it's been sitting, but the price is right, he's offering to finance it for me, and it's an appliance car that's known for reliability.
edit as of next weekend I won't be driving for a living as my primary income anymore either, most days it'll just see 5-10 miles total instead of the 100+ I normally drive a day now. I'll be keeping my current car on standby until I'm sure the Corolla is out of maintenance debt and reliable.

The condenser is leaking. I'm not sure if it's held any pressure whatsoever, or if it's actually completely empty. He got a quote to repair it before he parked it, they said it needed a condenser. The lines still all hooked up, so it's not like it's completely open to atmosphere.

What are the chances that sitting for so long with a leak will have caused issues with the compressor or anything else (besides the dryer)? I intend to spin the compressor a few revolutions by hand to make sure it's not locked up or rough, also intend to try applying power to the clutch to make sure it locks (engine off though, I don't want it to see full speed while empty).

2004 Corolla, FWIW.

STR fucked around with this message at 05:57 on Jun 1, 2019

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

I wouldn't give anything made out of rubber on that car more than a 50% chance of working past the first 2 weeks you drive it regularly.

RIP Paul Walker
Feb 26, 2004



I bought a car with an AC system that leaked all of its refrigerant out. My understanding is the oil mixes with the refrigerant during operation, does this also apply if it leaks out? Iím trying to figure out if I need to add oil, and if so, how much (entire quantity or just *some*).

I really donít want to yank the compressor to check itís oil level but Iíd rather do that than have an issue.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

RIP Paul Walker posted:

My understanding is the oil mixes with the refrigerant during operation, does this also apply if it leaks out?

Yes.

RIP Paul Walker posted:

Iím trying to figure out if I need to add oil, and if so, how much (entire quantity or just *some*).

Good luck. There is no way to tell how much leaked out. Fast leaks blow a whole lot out, slow leaks not so much.

If I were in your situation I'd figure out where the leak is first and see how bad it is. If it's very minor then add maybe 1/4 of the total oil volume. If it's a big leak......ehhhh...depends on how big. I'd add like 1/3 or more to "this hose literally explosively blew out" and everything changes if we're talking about collision damage taking out an evap....then I'd start with 1/3 for what was in the evap you had to take out and another 1/3 to account for what was carried out of the rest of the system. Which is probably slightly too much, but better a bit too much than too little.

The good thing is unless you go absolutely crazy overfilled oil won't hurt anything - it just slightly reduces system performance (less room for refrigerant). If you put way too much in it will slug the compressor. But playing the odds the system was probably filled at least somewhere around an appropriate level before the leak, so unless you have other information or suspicions I'd treat it that way.

Motronic fucked around with this message at 18:56 on Jun 17, 2019

RIP Paul Walker
Feb 26, 2004



Thank you, thatís helpful. I donít think the leak was too big, it held vacuum for hours, only half gone overnight. That could also be the well-used HF gauges leaking, too.

It takes 7.25oz (1991 MR2, long hoses), I think Iíll put in 2-3 ounces with dye and see what happens.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

Sounds like you're on the right track. Could be nothing more than natural seepage if your gauges/ports are leaky.

I don't suppose you can get your hands on some nitrogen to pressure test the system?

RIP Paul Walker
Feb 26, 2004



Motronic posted:

Sounds like you're on the right track. Could be nothing more than natural seepage if your gauges/ports are leaky.

I don't suppose you can get your hands on some nitrogen to pressure test the system?

No, your question made me do some reading tho. Iím going to take the gauges off after pulling a vacuum, see if it keeps overnight and if not... itís super tempting to use my smoke machine but I have no idea if the smoke will react in some sort of crazy way.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

If you can't find a leak just put in as little refrigerant as possible to allow it to run along with some dye. Run the system for a bit and it should be obvious with a black light where it's leaking.

Also, most ports won't hold vacuum since they're designed for pressure. When you take off the hoses the valve is just gonna suck in and fill the system partially or fully with air.

MrOnBicycle
Jan 18, 2008
Wait wat?

Crosspost from the Volvo thread, but my dads 2014 Volvo V70 has a problem when the A/C stops working intermittently when the temperatures get above ~28 degrees C, especially after being parked in the sun e.t.c. Going from shade / garage to highway driving is usually fine AFAIK. So stop and go traffic / parking in the sun = A/C shuts off. It comes on about 10-15 minutes later, and usually stays on but can shut off again even if driving at speed. The problem first arose last summer with the same symptoms, but has worked flawlessly and cools very well when temperatures got a bit lower. Engine is not overheating / reporting odd temperatures afaik, and the outside temperature sensor(s?) are working.

The consensus in the Volvo thread was that it probably isn't the A/C clutch on a car that new, but might instead be a pressure problem. I can't check pressures myself (unless it's OBD reported) since it hard to find the tools, and illegal to release pressure without proper equipment and certifications etc etc. I also don't have access to the car at the moment.

There are A/C "service/diagnostic" services that can be done where they check pressure, empty, test vacuum, refill, remove moisture etc etc (according to description), that I think I should get my dad to do. Like I wrote in the A/C thread, I'm driving the car to Berlin and just found out that it's gonna be 37-38 degrees those days...

Any ideas?

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

MrOnBicycle posted:

There are A/C "service/diagnostic" services that can be done where they check pressure, empty, test vacuum, refill, remove moisture etc etc (according to description), that I think I should get my dad to do.

Yes, that's a basic AC service. And there's nothing you can do unless you can check pressures. So if you can't do that then bring it somewhere that can.

IOwnCalculus
Apr 2, 2003





Motronic posted:

Yes, that's a basic AC service. And there's nothing you can do unless you can check pressures. So if you can't do that then bring it somewhere that can.

Could do some basic electrical testing to see if the computer is even calling for the clutch to engage, but yeah, anything other than that, you need to know system pressures.

MrOnBicycle
Jan 18, 2008
Wait wat?

Motronic posted:

Yes, that's a basic AC service. And there's nothing you can do unless you can check pressures. So if you can't do that then bring it somewhere that can.

Thanks, got him to try to book as service tomorrow. Best case, the service fixes it (maybe?), worst case they claim it has a massive leak and refuse to recharge it. Shouldn't be a possibility since it actually always works at lower temps, and cools like the day he got it (i.e very good)... right?

Jaded Burnout
Jul 10, 2004




Jaded Burnout posted:

It's a balmy 30ļC today and I think my AC is on the blink (in a 2004 UK Honda Civic) on account of it blowing hot air for the several minutes I could stand to wait for it to (not) cool down. My assumption is it needs a refrigerant refresh? It's a sudden development but I don't use the AC much after winter.

Is that a likely diagnosis, and is this a relatively simple task for a mechanic to do? I assume it's not something I should be trying myself on account of having to buy refrigerant and correctly dispose of the old stuff.

monsterzero posted:

Can you hear the compressor cycle on or off? It's usually pretty noticable on a Civic. If you pop the hood with the car running and AC off, then press the AC button you should hear a click, and the engine load (revs may dip momentarily and then go back up.)

Jaded Burnout posted:

I can hear stuff moving through the pipes as usual, which only happens when the AC is on. I'm assuming that means the compressor is running but I can test that next time I use the car; as you say it's very noticeable, in a "lights dim briefly" sort of way.

monsterzero posted:

Anyway, sudden no AC doesn't sound like a slow leak you could bandaid with a charge kit. You should head over to Motronic's thread and ask if you need more freeon.

So, I am here, for your sage wisdom. I only skimmed the OP because it was full of advice on how to do this on your own which I'm definitely not up to doing on account of it apparently being not only troublesome for dealing with the waste refrigerant but also extremely dangerous.

MrOnBicycle
Jan 18, 2008
Wait wat?

MrOnBicycle posted:

Thanks, got him to try to book as service tomorrow. Best case, the service fixes it (maybe?), worst case they claim it has a massive leak and refuse to recharge it. Shouldn't be a possibility since it actually always works at lower temps, and cools like the day he got it (i.e very good)... right?

Update: A/C Dude said it was pointless to do an A/C service unless we wanted to waste $280 (which was nice of him) as the car was cooling down to 4 degrees from a single vent. He couldn't see anything immediatly wrong with the A/C while inspecting it, and didn't have much of an explanation to why it stops working when it's very hot outside.

A/C worked 95% of of the trip to Berlin, only giving out after 10 minutes after driving away from Berlin (where it sat for an hour in the sun while we loaded the stuff). I guess we should just leave well enough alone for now.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

Jaded Burnout posted:

So, I am here, for your sage wisdom. I only skimmed the OP because it was full of advice on how to do this on your own which I'm definitely not up to doing on account of it apparently being not only troublesome for dealing with the waste refrigerant but also extremely dangerous.

Find a shop that does AC repair.......this sounds like you basically need to start with checking system pressures. Happy to help evaluate their diagnosis/quote, but like I'm sure I put in the OP: this almost always starts with needing a set of gauges to get anywhere into a diagnosis.

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Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

MrOnBicycle posted:

Update: A/C Dude said it was pointless to do an A/C service unless we wanted to waste $280 (which was nice of him) as the car was cooling down to 4 degrees from a single vent. He couldn't see anything immediatly wrong with the A/C while inspecting it, and didn't have much of an explanation to why it stops working when it's very hot outside.

A/C worked 95% of of the trip to Berlin, only giving out after 10 minutes after driving away from Berlin (where it sat for an hour in the sun while we loaded the stuff). I guess we should just leave well enough alone for now.

You should bring it to someone who can be arsed to at least check the static and running pressures.

I'm confused about "the car was cooling down to 4 degrees from a single vent" If by this you mean it was working properly as far as cooling, just not out of the right vents then you have a different issue that likely involves the blend doors or control panel.

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