80 series AC intel? (1 Viewer)

[landcruiser3DP]

You didn't ask this but here goes: did you know that butane is a refrigerant, a flammable one but one that is interesting because you see the effects of ambient temperature on its boiling point. Take a butane lighter and hold it in your hand, get it nice and warm and it will light every time. take the same lighter and put it in the fridge for an hour, take it out and try to get it going... you can't, not till the heat from your hand warms the butane up enough to boil it and create gas and enough vapor pressure to drive up to the flame holder. Ever notice how a propane torch gets cold the longer you run it, and the flame gets smaller? That's because the vapor pressure in the canister of propane is getting lower with the temperature of the remaining liquid. Propane is also a refrigerant, a really good one actually. When the liquid refrigerant gets cold its boiling point goes down as does its vapor pressure. This is what the black and white temp chart is showing you for 134a. I used butane as an example because a lighter is something anybody can purchase, experiment with and see the direct results of vapor pressure.

On to what you did ask:

You can't do AC work without gauges, a vacuum pump and a decent kitchen thermometer (goes in a vent in the car to measure temp delta between ambient and refrigerated air).
I have a set up from harbor freight, yeah, yeah, yeah, get over yourselves; for the DIY'er they work fine. Get the good pump, not the cheap one, it pulls down to 3 microns vacuum.

Answers to your questions:
1) 0.90Kg max is the physical weight of the liquid refrigerant put into an evacuated system. If you look at the side of a can of 134 it will tell you how much is in the can. For example the black and white cans in your pic show 12 oz (340 grams) you need 900 grams, the cans are 340 so 900 /340 = 2.64 cans for a max fill. I'll let you do the math for the min fill.
Always add refrigerant through the low side, The first two cans can be run in, but you have to weigh the third can on a fish scale, with the hose attached, to ensure you don't overfill the system. Sometimes the system will be perfectly happy at the min fill value, still have to weigh the correct amount of refrigerant. Getting the second can in, and the partial third, can be a long process. As the refrigerant boils off in the can and becomes a gas, it cools the remainder in the can, the colder the can gets the lower the pressure in the can. (see the black and white temp chart you show) When the temp of the refrigerant in the can, and its subsequent pressure, is lower then the pressure in the system, it stops feeding gas into the system, and you can wait for the can to slowly...oh so slowly... feed gas into the system or you can force the process by raising the boiling temp of the refrigerant in the can by dunking it in a pan of warm water.

2) you add the new oil into the new dryer before you attach it to the system. It will distribute itself around when the system is running.

3) Answered with 1
4) The temp chart you show is the pressure 134A is at in a still (not moving) system at the temp shown. If you hook up the gauges to the high and low side and the system hasn't run for a good while the pressure across the gauges will be equal. At 75F the pressure =78.7psi. Near on useless information except to tell you there is indeed refrigerant in the system.

The meaning-full chart will compare the low and high side readings at the ambient temp.
View attachment 2973959

5) mostly answered with 1, as for measuring air or moisture in the lines, you can't. That's beyond the DIY'er. If that's the concern, take it someplace, and have the refrigerant recovered (not for you to reuse, just so its not released to atmosphere). Then change the dryer, draw a vacuum for an hour or so and fill per recommendation.

I suggest you go to the Sanden web site and poke around their technical data.
This is their quick trouble shooting chart.

https://www.sanden.com/objects/SANDEN_SYSTEM_DIAGNOSIS_CHART.pdf

and their trouble shooting guide.

https://www.sanden.com/objects/3_-_Troubleshooting_-_Web_01.pdf

Here is some of their tech bulletins. Even if you don't fully understand them, read through a couple, it will boost your general understanding of AC systems.

Sanden USA

Sanden, Sanden USA

www.sanden.com

hey RM,
thanks a ton for that. the practical butane/propane examples are super. working though the links now.
on the numbers some of it can get tricky so in case someone is following along i thought i would post a breakdown.
for what it is worth i always get thrown with ounces. for some dumb reason i sometime assume it is a volume measurement in cans like that.

 

[landcruiser3DP]

^^^^^

I would like for you to take a sheet of paper and place it over the lower half of the diagram and NOTES written there....and never look at it again. As most of it is wrong. In fact, anyone reading this.....please disregard the notes.

I am going to explain in a simple way how A/C systems work (in general) and it is true of ALL auto A/C systems.

Let us begin by recognizing what your A/C system does. It cools the cabin and at the same time removes humidity.

How does it accomplish this? An A/C doesn't bring in cool air. It removes hot air via multiple exchanges of heat. The absence of heat/hot is what we think of as being cool.

Let' start at the COMPRESSOR. Its job is two fold. It 'pumps' the refrigerant though the system and 'compresses' the gases that enter it (hence its name). A compressor should NEVER have a liquid go through it (liquids are not compressible).

From the compressor the hot compressed gas enters the CONDENSER. Air flowing across/through the condenser cools the hot gas and it 'condenses' to liquid form. At the same time it releases the heat that was absorbed from the cabin and created when the gases were compressed. It 'sheds' the heat if you will.

From the condenser the high pressure liquid refrigerant enters the DRIER. Here the desiccant in the drier is supposed to capture any moisture that may be present in the refrigerant. We do NOT want moisture in the system at all for a variety of reasons. The high pressure liquid refrigerant then leaves the Drier flows though the hard lines to the EVAPORATOR but first must go through the TXV (Thermal Expansion Valve).

It enters the TXV who's job is to regulate the amount (trying to keep it constant). Your TXV is the BOSS of the system and basically has the final say. IF all is working well the high pressure liquid (with a little gas) is regulated to a lower pressure as it enters the evaporator.

The liquid here is quickly becoming cooler as it enters the evaporator. It will turn into a gaseous state as the cabin temperature tries to heat it and it 'boils'. This is where the 'magic' happens. The gas in the evaporator absorbs the heat from the cabin and takes it along to the compressor where the process starts all over again.

So these heat exchanges remove heat and moisture from the cabin. It takes several cycles (air/heat) for the air to start feeling cooler and the cabin to actually cool down. The moisture in the air/cabin condenses on the fins of the evaporator and is drained away and out of the vehicle. That is the puddle of water under your vehicle that you see when it is stationary.

So to recap....the Evaporator ABSORBS heat (collects it) and the condenser DISSIPATES heat (sheds it). The evaporator after a few cycles physically becomes cold itself....so the combination of removing heat and the blower fan moving air across the now cool surface of the evaporator is what gives us cool air at the vents.

The main point to remember is that the system REMOVES heat. When you fill your system with refrigerant ...you are not 'pouring in the cool' to be circulated. You are creating a 'system' that absorbs and transfers heat to the outside.

nice! thanks FK.
so i was kind of hoping to draw this up properly. would you mind just letting me follow this one through with a written attempt or two?(!) some people want to draw a map of the world by memory before they die. i want to draw a heating and cooing cycle...

1. low pressure warm air from the condensor enters the compressor (this air is warm because it has absorbed heat from the cabin air. and it is low pressure because it oases though the TXV which allowed it to decompress).

2. the compressor physically compressed this air which leaves as a hot, high pressure gas?

3. this gas enters the condensor and the hot, high pressure air travels through a bunch of tubes as the - well the fan pulls air over the fins, the fins mechanically dissipate heat and any air blown through the condensor cools the hot tubes and fins?

4. this turns the hot, high pressure air into a cool, high pressure fluid (?!) - or maybe it is still a gas here? - which enters the dryer. in the dryer rhere is a solid desiccant which pulls out moisture and holds it in the desiccant?

5. the cool high pressure liquid enter rhee TXV which has a mechanical orifice. when this orifice opens it allows cool high pressure gas to enter the condensor. the cool high pressure gas travels through the condensor which has fins on it. as warm air that is on the fins cools though convection and warm air rhat is near the fins cools though conduction.
also water is produced as warm air adjacent to the fins reaches its "dew point temperature" and as this air is cooled it also produces water (based upon some law of thermodynamics i don't understand).

6. warm, low pressure gas (it absorbed heat from the cabin air and the pressure was dropped when it got dumped in though the expansion valve) from the condensor is sucked into the compressor (because it is pushing out the other end) and this warm, low pressure gas is then into the compressor where it is turned into a hot, compressed, high pressure gas.

7. the circuit continues along to the condensor.

 

[landcruiser3DP]

You guys are sharing great information but I will repeat again that the chart is useful in confirming there is air in the system. Air is a noncondensable gas and will raise the pressure of the refrigerant for the given temperature. If the static pressures are higher than what the chart shows, the system is contaminated.



To clarify, the X part of the TXV stands for "expansion" which means this is where the magic of "cooling" happens. The coldest point of the system should be directly after the TXV and from there, its temperature will increase with the heat added in the evaporator.

Not necessarily relevant to help the OP, but clarifying nonetheless.

hi TD,
thanks a LOT for this. do you mind if i try to follow up and wrap my head around rhis a little more? the "PSIG" i looked up and i guess it is PSI but as it relates to air. or something.
but can you help me right this static pressure business? i get that the low pressure line is going to read different than the high pressure line. and i can kind of see the low pressure line is the entry to the compressor and the high pressure line is the exit. there was a third valve there that i have to - well maybe it is used for adding gas or dye. anyway.
"Saturation pressure-temperature data for R134a (psig) (*red italics indicate inches of mercury below atmospheric pressure) at:
75d F = 78.7 PSIG
which i can read with a manifold gauge aluminum the system has been sitting and it has equalized? so i see this value in the low and high lines?

then for the "R135a Temperature pressure chart"at 75d F i should see
35-45 psi low side and
150-170 psi high side
- - - well for any system that contains R134a gas? or what? i mean different systems will have differ t sizes and even the same systems will have different weights of r134a in them? or vapor? or oil?
i guess i don't white follow what rhis low side high side chart is telling me? it's like the gas performs optimallly if it is at these pressures (relative to the ambient temp)? or what?

lastly FSM seemed to want you to run the engine at some RPM? or what were the FSM diagnostics? just the sight glass since you are reading manifold pressures based upon an r134a chart that is not in the FSM?

i mean can i ask you to help me a little more with that stuff?(!)

 

[BILT4ME]

OMFG.

 

[Rusty Marlin]

Ummm, No.
Always think of a refrigeration system as moving heat around. You can't move cold anything, there's no energy in it.
I'll make the corrections in your text. Its going to be a little confusing because you didn't start at one end of the system or the other (highest temp or lowest temp.) but bear with it to the end. I'll do my best to lead you through.
Some things to keep in mind:
1) Compressors don't suck in anything, there is no such thing as suction, pressure differentials move gasses and fluids around.
2) heat always moves from high to low, energy always moves from high to low. You can't move cold anywhere. Everybody's Mom yelled at them to "shut the door, your letting the cold in!"... in reality you are letting the hot air out and the escaping hot air going out the top of the door frame allows cold air to be driven in the bottom of the door by atmospheric pressure.

nice! thanks FK.
so i was kind of hoping to draw this up properly. would you mind just letting me follow this one through with a written attempt or two?(!) some people want to draw a map of the world by memory before they die. i want to draw a heating and cooing cycle...

1. low pressure warm air from the condensor enters the compressor (this air is warm because it has absorbed heat from the cabin air. and it is low pressure because it oases though the TXV which allowed it to decompress).

Low pressure, hot refrigerant vapor (there is no air in the AC system, only refrigerant) exits the evaporator (in the dash) and is pushed into the compressor (remember, there is no such thing as suction), by high pressure liquid entering the evaporator through the TXV (on the incoming side of the TXV is high pressure liquid). The High pressure liquid is flashed to vapor in the evaporator. When it flashes to vapor the refrigerant's energy is lowered, hot outside air pushed through the evaporator fins by the fan, transfers its energy to the now cold vapor, heating it back up. The now cold air leaves the evaporator and cools the cabin by hot cabin air transferring it's energy to the cold air blowing out the vents.

2. the compressor physically compressed this air which leaves as a hot, high pressure gas?

The Compressor takes the hot low pressure refrigerant vapor that came from the evaporator and adds energy by raising it's pressure. The refrigerant exits the compressor as a high pressure gas and enters the condenser.

3. this gas enters the condensor and the hot, high pressure air travels through a bunch of tubes as the - well the fan pulls air over the fins, the fins mechanically dissipate heat and any air blown through the condensor cools the hot tubes and fins?

Yes, but there is no air in the AC system, only refrigerant.

4. this turns the hot, high pressure air into a cool, high pressure fluid (?!) - or maybe it is still a gas here? - which enters the dryer. in the dryer rhere is a solid desiccant which pulls out moisture and holds it in the desiccant?

The refrigerant is cooled and condensed to a high pressure liquid, and yes this passes through the dryer where any residual moisture is trapped by the desiccant. Think of this like hot steam condensing on a cold window. Taking a hot vapor and turning back into a liquid.

5. the cool high pressure liquid enter rhee TXV which has a mechanical orifice. when this orifice opens it allows cool high pressure gas to enter the condensor. the cool high pressure gas travels through the condensor which has fins on it. as warm air that is on the fins cools though convection and warm air rhat is near the fins cools though conduction.
also water is produced as warm air adjacent to the fins reaches its "dew point temperature" and as this air is cooled it also produces water (based upon some law of thermodynamics i don't understand).

You have your terms messed up. The high pressure liquid passes though the TXV into the Evaporator and is instantly vaporized into gas because the evaporator is a low pressure zone compared to the inlet side of the TXV. Remember the propane example I gave you. In the torch tank is liquid propane at the bottom and vapor (gas) propane above the liquid. When the valve is opened the vapor is released, lowering the pressure in the tank and the gas is driven out of the nozzle by more liquid propane boiling off. The energy to boil this liquid propane is provided by the ambient temperature around the tank. When the nozzle is closed the vapor pressure in the tank increases until no more liquids can boil off, it goes into equilibrium. this is what happens when you turn off the AC. the system goes into equilibrium and there is a mix of gas and liquid in the system. When you turn on the AC the Compressor and Condenser create a high pressure area and the TXV and Evaporator create a low pressure area.

The water dripping out the bottom of the evaporator box: The fins of the Evaporator are cold, the hot moist outside air is driven across these fins by the fan (in the dash). The moisture drops out of the air as it's cooled, exactly like a cold glass of iced tea sweats. Its the same mechanism.

6. warm, low pressure gas (it absorbed heat from the cabin air and the pressure was dropped when it got dumped in though the expansion valve) from the condensor is sucked into the compressor (because it is pushing out the other end) and this warm, low pressure gas is then into the compressor where it is turned into a hot, compressed, high pressure gas.

Yes, Except, there is no such thing as suction!

7. the circuit continues along to the condensor.

And it goes round and round as long as energy is put into the system via the engine driving the compressor.

 

[gummycarbs]

@landcruiser3DP you're confusing "air" with "gas".

There are four states of matter: solid, liquid, gas, and plasma. If your refrigerant is solid, then you have parked on the far side of the moon. If it's plasma, then it would appear that Russia has launched nukes.

You only need to be concerned with the transition from liquid to gas. This "makes cold". It's exactly the same reason that spraying a can of compressed air chills the can.

 

[flintknapper]

@landcruiser3DP you're confusing "air" with "gas".

There are four states of matter: solid, liquid, gas, and plasma. If your refrigerant is solid, then you have parked on the far side of the moon. If it's plasma, then it would appear that Russia has launched nukes.

You only need to be concerned with the transition from liquid to gas. This "makes cold". It's exactly the same reason that spraying a can of compressed air chills the can.

^^^^

Actually there are 5.

There is what my Wife says 'Matters'.

Somehow.....we always have to go with that.

 

[BILT4ME]

^^^^

Actually there are 5.

There is what my Wife says 'Matters'.

Somehow.....we always have to go with that.

When I was in Jr. High, science teacher, Mr. Graff asked PJ: "What's matter?"

PJ replied as he lifted his head from his desk........ "Awww, nothin'."





True story.

 

[FMC80]

Suffice to say school is very different today than 69 years ago when @BILT4ME was in junior high.

Today’s science teacher will ask a single person, “It, they, him/her, what is matter”

It, they, him/her’s response: “I’m an elephant and need special accommodations for my bathroom. This is my truth”

Probably true story.


And Jk @BILT4ME. Love you. Mean it.

Back to tech: to the OP, this maintenance you’re deciding to embark on seems to be above and beyond your abilities so I recommend you outsource this job to a reputable shop near you. AC systems aren’t for the faint of heart and a proficient level of understanding is required not to **** it up.

 

[Rusty Marlin]

hi TD,
thanks a LOT for this. do you mind if i try to follow up and wrap my head around rhis a little more? the "PSIG" i looked up and i guess it is PSI but as it relates to air. or something.

PSIG, means Pounds Per Square Inch, Gage, as in read directly off the Gage with "Zero" being at normal standard atmospheric pressure.
When measuring a vacuum it's customary to read the value in InHg, Inches of Mercury. It's the same measurement method as finding Barometric pressure in the atmosphere. If one is looking for a more precise value they might use ft of water, as a pure vacuum can hold up approximately 28Ft of water vs only 30" of Hg. If the gage were labeled in PSIA, pounds per square inch, absolute, 14.7 would be were the zero is on the PSIG gage.
Google how barometers work and are made if this doesn't make sense.

In the above image, notice how the 0-30 inHg section is identical to the 0-15Psi region?
This is because 14.7 psi is standard atmospheric pressure, and a "pure" vacuum is the absence of the 14.7Psi or 30inHg.

but can you help me right this static pressure business?

Static = still, ie not moving. Hook a gage up to a can of 134A and to the high or low pressure port of the not running and AC system and you'll get the same answer provided they are at the same temp and the AC system is uncontaminated with air or moisture.

i get that the low pressure line is going to read different than the high pressure line. and i can kind of see the low pressure line is the entry to the compressor and the high pressure line is the exit. there was a third valve there that i have to - well maybe it is used for adding gas or dye. anyway.

Ignore it. Use the low side for all inputs. DO NOT EVER add refigerant to a operating AC systme through the High pressure port. You'll explode the canister of refigerant if you expose it to the high side pressure.

"Saturation pressure-temperature data for R134a (psig) (*red italics indicate inches of mercury below atmospheric pressure) at:
75d F = 78.7 PSIG
which i can read with a manifold gauge aluminum the system has been sitting and it has equalized? so i see this value in the low and high lines?

Only when the system is stopped and at 75F. Assuming ambient temp is 75: If the vehical has been running, the AC system will heat soak and will be at some temperature above ambient. This is one of the reasons the static pressure of the system is not good for anything other than to tell you the system actually has refrigerant in it. It takes several hours for a vehical engine and all other systems to return to ambient temperature.

then for the "R135a Temperature pressure chart"at 75d F i should see
35-45 psi low side and
150-170 psi high side
- - - well for any system that contains R134a gas? or what? i mean different systems will have differ t sizes and even the same systems will have different weights of r134a in them? or vapor? or oil?

Yes, that's how it works. If you change refrigerants you use different pressures. If the system is contaminated or otherwise not functioning properly the pressures won't match the tables.
hence the need for the Trouble Shooting and Diagnostics tables:

i guess i don't white follow what rhis low side high side chart is telling me? it's like the gas performs optimallly if it is at these pressures (relative to the ambient temp)? or what?

ABSOLUTELY! If the system gets out of its optimal charge or it has contaminates, the system doesn't work optimally.
See table above.

lastly FSM seemed to want you to run the engine at some RPM? or what were the FSM diagnostics? just the sight glass since you are reading manifold pressures based upon an r134a chart that is not in the FSM?

i mean can i ask you to help me a little more with that stuff?(!)

The system needs to be stable to get proper readings. Both thermally and RPM. The FSM wants you to run the system at an RPM higher than the kick up RPM. Idle is 625, kick up when AC turns on is around 800-ish. So the FSM wants 1200 or something like that, its been a while since I read that part.
Its just so the system is stable.

 

[landcruiser3DP]

PSIG, means Pounds Per Square Inch, Gage, as in read directly off the Gage with "Zero" being at normal standard atmospheric pressure.
When measuring a vacuum it's customary to read the value in InHg, Inches of Mercury. It's the same measurement method as finding Barometric pressure in the atmosphere. If one is looking for a more precise value they might use ft of water, as a pure vacuum can hold up approximately 28Ft of water vs only 30" of Hg. If the gage were labeled in PSIA, pounds per square inch, absolute, 14.7 would be were the zero is on the PSIG gage.
Google how barometers work and are made if this doesn't make sense.
View attachment 2976453
In the above image, notice how the 0-30 inHg section is identical to the 0-15Psi region?
This is because 14.7 psi is standard atmospheric pressure, and a "pure" vacuum is the absence of the 14.7Psi or 30inHg.

Static = still, ie not moving. Hook a gage up to a can of 134A and to the high or low pressure port of the not running and AC system and you'll get the same answer provided they are at the same temp and the AC system is uncontaminated with air or moisture.

Ignore it. Use the low side for all inputs. DO NOT EVER add refigerant to a operating AC systme through the High pressure port. You'll explode the canister of refigerant if you expose it to the high side pressure.

Only when the system is stopped and at 75F. Assuming ambient temp is 75: If the vehical has been running, the AC system will heat soak and will be at some temperature above ambient. This is one of the reasons the static pressure of the system is not good for anything other than to tell you the system actually has refrigerant in it. It takes several hours for a vehical engine and all other systems to return to ambient temperature.

Yes, that's how it works. If you change refrigerants you use different pressures. If the system is contaminated or otherwise not functioning properly the pressures won't match the tables.
hence the need for the Trouble Shooting and Diagnostics tables:
View attachment 2976477

ABSOLUTELY! If the system gets out of its optimal charge or it has contaminates, the system doesn't work optimally.
See table above.

The system needs to be stable to get proper readings. Both thermally and RPM. The FSM wants you to run the system at an RPM higher than the kick up RPM. Idle is 625, kick up when AC turns on is around 800-ish. So the FSM wants 1200 or something like that, its been a while since I read that part.
Its just so the system is stable.

thanks. i'm catching up here.
can you help me with the steps if i want to run the compressor out to have it serviced? should run it to a shop and have them vacuum refrigerant out? i couldn't quite tell if i can do this myself with this "vacuum pump - air or aerated" for $26 from the AC shop they were going to sell me along with the manifold gauge?
i mean i didn't quite get the steps for the - well is it - refrigerant drain, vacuum and fill? i did catch someone said i should get a vacuum that "pulls to within 3 microns".
say i want to pull the compressor, can i drain refrigerant with something i buy from the shop or do i run it to a shop and pay them to do that?
then - well FSM seems to want me to run engine at idle with AC on for ten minutes. then drain. then disconnect.
also, can i easily (?) snake the compressor belt out, cap the open lines, and run the compressor over to the AC shop for service? worst comes to worst they take a look at it and tell me to put it back in?(!)
THANKS

 

[bhsdriller]

I'm not even sure what the purpose of this thread was now

 

[ChaseTruck]

I'm not even sure what the purpose of this thread was now

Asking questions, as per usual. Nevermind the previous & highly explicit answers...

 

[gummycarbs]

should run it to a shop and have them vacuum refrigerant out?

Yes, you should take the vehicle to an AC shop to have the refrigerant removed.

Since you still haven't wrapped your head around the subject, you should just take the vehicle to an AC shop for the entire service.

i couldn't quite tell if i can do this myself with this "vacuum pump - air or aerated" for $26 from the AC shop they were going to sell me along with the manifold gauge?

Nobody here knows what service your AC shop was selling you. You should ask them.

 

[BILT4ME]

I'm not even sure what the purpose of this thread was now

 

[flintknapper]

thanks. i'm catching up here.
can you help me with the steps if i want to run the compressor out to have it serviced? should run it to a shop and have them vacuum refrigerant out? i couldn't quite tell if i can do this myself with this "vacuum pump - air or aerated" for $26 from the AC shop they were going to sell me along with the manifold gauge?
i mean i didn't quite get the steps for the - well is it - refrigerant drain, vacuum and fill? i did catch someone said i should get a vacuum that "pulls to within 3 microns".
say i want to pull the compressor, can i drain refrigerant with something i buy from the shop or do i run it to a shop and pay them to do that?
then - well FSM seems to want me to run engine at idle with AC on for ten minutes. then drain. then disconnect.
also, can i easily (?) snake the compressor belt out, cap the open lines, and run the compressor over to the AC shop for service? worst comes to worst they take a look at it and tell me to put it back in?(!)
THANKS

Please take it to a shop and have them do ALL the work you need to have done.

You don't need to understand it, you just need cold air.

You can not 'drain' refrigerant, it must be 'evacuated' (captured using specialized machinery). The DIYer (without equipment) can only let refrigerant (in its gaseous state) escape into the atmosphere. R134a is not an ozone-destroying agent, but it is a greenhouse gas, and is illegal to vent.

I know you want to understand the how's and why's of A/C and I can appreciate that. But all of that info is available on line. It isn't useful for us go over the principles of refrigeration here. Only to discuss how it applies specifically to our vehicles.

This thread is getting well outside of those constraints....and frankly a bit painful as well.

So I am out of here. Hope it works out for you. Summer is on its way.

 

[landcruiser3DP]

Please take it to a shop and have them do ALL the work you need to have done.

You don't need to understand it, you just need cold air.

You can not 'drain' refrigerant, it must be 'evacuated' (captured using specialized machinery). The DIYer (without equipment) can only let refrigerant (in its gaseous state) escape into the atmosphere. R134a is not an ozone-destroying agent, but it is a greenhouse gas, and is illegal to vent.

I know you want to understand the how's and why's of A/C and I can appreciate that. But all of that info is available on line. It isn't useful for us go over the principles of refrigeration here. Only to discuss how it applies specifically to our vehicles.

This thread is getting well outside of those constraints....and frankly a bit painful as well.

So I am out of here. Hope it works out for you. Summer is on its way.

thanks. i was trying to confirm i need to take it to shop to evacuate the refrigerant or if i could do this myself. but i think it requires expensive equipment to do this. so i guess it has to go to a shop.
the next question was once the refrigerant is evacuated - if i can pull the compressor and have it serviced at the AC repair/supply place that hooked me up. and if so if there are any cautions to pulling it.
seems like it makes sense to service the compressor as long as the system is going to be apart.

 

[ToyotaDon]

Yes, you can pull the compressor after the refrigerant is recovered, but hardly anybody "services" compressors. If there is something wrong with it, that will be determined while the compressor is still in the vehicle and running. If it's noisy or leaking (or if metal is found in the lines when opened) the compressor would need to be replaced.

 

[landcruiser3DP]

Yes, you can pull the compressor after the refrigerant is recovered, but hardly anybody "services" compressors. If there is something wrong with it, that will be determined while the compressor is still in the vehicle and running. If it's noisy or leaking (or if metal is found in the lines when opened) the compressor would need to be replaced.

hey man. thanks a lot for that. i started thinking i should take an opportunity to service it like i would a starter.
i talked to a local guy yesterday who is very good with most stuff and i think he was saying he'd like to see me do the fan clutch first, then vacuum the system and fill. the reasoning being (i think) that partly functioning fan clutch would affect pressures and make them higher (i'm supposedly at 260/40 but i don't think we got it to the proper rpm).
and i also have to admit i had a hard time diagnosing if the fan clutch is on its way out or not (it doesn't "spin"). but he also seemed to thing the new values won't be accurate if the fan clutch is old anyway.
so the thought was to replace the fan clutch and then vacuum and fill and go from there.
can i ask if you have any expert input on either of those?

 

[flintknapper]

hey man. thanks a lot for that. i started thinking i should take an opportunity to service it like i would a starter.
i talked to a local guy yesterday who is very good with most stuff and i think he was saying he'd like to see me do the fan clutch first, then vacuum the system and fill. the reasoning being (i think) that partly functioning fan clutch would affect pressures and make them higher (i'm supposedly at 260/40 but i don't think we got it to the proper rpm).
and i also have to admit i had a hard time diagnosing if the fan clutch is on its way out or not (it doesn't "spin"). but he also seemed to thing the new values won't be accurate if the fan clutch is old anyway.
so the thought was to replace the fan clutch and then vacuum and fill and go from there.
can i ask if you have any expert input on either of those?

YES....good plan of attack.