| Author |
Message |
dhaavers
Samba Member
Joined: March 19, 2010
Posts: 7757
Location: NE MN (tinyurl.com/dhaaverslocation)
|
 Posted: Tue Jun 09, 2015 7:12 pm Post subject: Red Tek real time help...<EDIT - Much better now!> |
 |
|
Charging with my Red Tek today, stopped with only about 2 cans in, reading
22 low side & 275 on the high; vent temps never got lower than 62...
After a failed "quick & dirty" attempt a few years ago, I was so sure I was
doing it right this time...& I've spent plenty of money to get to this point! 
Here's my story...
In the last month:
- new REAL Sanden 508 compressor w/5 oz. new PAG oil
- new barrier hoses, fittings & o-rings (+ 1/3 oz. oil each in hi & low lines)
- new R/D (+ 1/3 oz. oil)
- new binary switch (never had one w/stock early '86 system)
- new parallel-flow condenser
- new expansion valve ("L" type) & cork insulation
- clean, fully flushed evaporator (+ 2 oz. oil)
- new plastic baffles at condenser/radiator
Prep for today:
- pulled hard vacuum for 4 hours yesterday (2.5cfm HF pump)
- help vacuum overnight...yay!
- plenty of Red Tek on hand, ready to start in the morning!
Procedure today:
- ENGINE OFF: first can charged slowly to vacuum on high side (valve-down)
- Engine on @ high idle, box fan in front of condenser on HIGH
- AC fan on high, AC thermostat on MAX, compressor running, radiator fan on
- reading about 10 low/150 high before starting second can
- second can in slowly on low side, numbers go up to 20 low/250 high
- vent temps sometimes as low as 62, finished at about 66
- Engine off to rest, then bled some out to try to get to lower vent temps...
- Engine on again; now reading about 15 low/200 high
- started adding third can until numbers went to about 22 low/275 high
- vent temps never lower than 64 this time...
Sooooo...WTH???
Seems like my low is too low & high is too high. With only 2 cans in,
maybe should I just add another can & try to get to 30 on the low side?
Wife is not gonna be happy with only 65 degrees at the vents... 
Talk to me, Samba...
- Dave
_________________
86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS>
Last edited by dhaavers on Wed Jun 10, 2015 10:49 am; edited 1 time in total |
|
| Back to top |
|
 |
morymob
Samba Member
Joined: November 09, 2007
Posts: 4683
Location: east-tn
|
| Posted: Tue Jun 09, 2015 7:51 pm Post subject: |
|
|
| Did ac work before u swapped aii those parts?? Sounds like a mostly closed expansion valve or stuck in this position. After u get the pressures & shut of eng how long 4 system to equalize press? |
|
| Back to top |
|
|
dhaavers
Samba Member
Joined: March 19, 2010
Posts: 7757
Location: NE MN (tinyurl.com/dhaaverslocation)
|
| Posted: Tue Jun 09, 2015 8:00 pm Post subject: |
|
|
AC has never worked the 6 years we've had this van.
New expansion valve from GW (4 Seasons brand).
Engine off, seems like it took about a minute to equalize at about 110 psi...
_________________
86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS> |
|
| Back to top |
|
|
morymob
Samba Member
Joined: November 09, 2007
Posts: 4683
Location: east-tn
|
| Posted: Tue Jun 09, 2015 8:09 pm Post subject: |
|
|
| Last time i saw hi side like that was a plugged input filter screen in expansion valve on one of my 84's. Kept fooling with it not knowing the problem & blew hi side hose close to drier. Not familiar with that valve,, had the ac dropped, opened to clean inside the box but didn't need sys opened, run u out withe red tek before i put tunnel back up. It's a 86 tin top syncro. |
|
| Back to top |
|
|
shadetreetim
Samba Member
Joined: January 10, 2011
Posts: 1994
Location: Riverside, California
|
| Posted: Tue Jun 09, 2015 8:18 pm Post subject: |
|
|
My Redtek install got colder than that with only 2 cans, but I needed closer to 3 cans to get it good and cold.
_________________
Tim Potts
Doing my best every time I drive it to dispel the myth these Vanagons have to be slow!
'89 Vanagon Bluestar/Country Homes 1.8T & .77 4th
'74 Jeep CJ5 |
|
| Back to top |
|
|
markz2004
Samba Member
Joined: November 13, 2007
Posts: 944
Location: Portland, OR
|
| Posted: Tue Jun 09, 2015 8:34 pm Post subject: Re: Red Tek real time help... |
|
|
| dhaavers wrote: |
- ENGINE OFF: first can charged slowly to vacuum on high side (valve-down)
|
I thought you could only safely charge to the LOW pressure side, where the pressure in the system is LOWER than the contents of the can..... |
|
| Back to top |
|
|
markz2004
Samba Member
Joined: November 13, 2007
Posts: 944
Location: Portland, OR
|
|
| Back to top |
|
|
Altoona
Samba Member
Joined: November 14, 2011
Posts: 505
|
| Posted: Tue Jun 09, 2015 8:39 pm Post subject: Re: Red Tek real time help... |
|
|
This is why this worked for the first can into a hard vacuum.
| markz2004 wrote: |
| dhaavers wrote: |
- ENGINE OFF: first can charged slowly to vacuum on high side (valve-down)
|
I thought you could only safely charge to the LOW pressure side, where the pressure in the system is LOWER than the contents of the can..... |
|
|
| Back to top |
|
|
dhaavers
Samba Member
Joined: March 19, 2010
Posts: 7757
Location: NE MN (tinyurl.com/dhaaverslocation)
|
| Posted: Tue Jun 09, 2015 8:40 pm Post subject: Re: Red Tek real time help... |
|
|
| markz2004 wrote: |
| dhaavers wrote: |
- ENGINE OFF: first can charged slowly to vacuum on high side (valve-down)
|
I thought you could only safely charge to the LOW pressure side, where the pressure in the system is LOWER than the contents of the can..... |
Read again: at vacuum, the system was -29 psi before putting in that first can... 
_________________
86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS> |
|
| Back to top |
|
|
markz2004
Samba Member
Joined: November 13, 2007
Posts: 944
Location: Portland, OR
|
| Posted: Tue Jun 09, 2015 8:49 pm Post subject: Re: Red Tek real time help... |
|
|
| dhaavers wrote: |
| markz2004 wrote: |
| dhaavers wrote: |
- ENGINE OFF: first can charged slowly to vacuum on high side (valve-down)
|
I thought you could only safely charge to the LOW pressure side, where the pressure in the system is LOWER than the contents of the can..... |
Read again: at vacuum, the system was -29 psi before putting in that first can... |
You did great by getting a good vacuum. However, I believe the correct procedure is to introduce the Redtek into the LOW side while having a high engine idle and having/getting the AC compressor to cycle. I haven't heard of someone, or read any recommendations for introducing any refrigerant into the high side valve. Actually, I believe reading that it is quite dangerous to do so as the can may explode.
If your compressor will not cycle because your system is completely empty, there is a way to 'jump' the compressor to get it to cycle.
It sound like you have a good AC system, but you put the redtek into the wrong side of the system.
_________________
87 Westy, 250k GW 2.4 - 2.0 , 16" wheels |
|
| Back to top |
|
|
Howesight
Samba Member
Joined: July 02, 2008
Posts: 3274
Location: Vancouver, B.C.
|
| Posted: Tue Jun 09, 2015 8:52 pm Post subject: |
|
|
| dhaavers wrote: |
AC has never worked the 6 years we've had this van.
New expansion valve from GW (4 Seasons brand).
Engine off, seems like it took about a minute to equalize at about 110 psi... |
What were the ambient temps when you were at two cans of Red Tek and what is/was the ambient temp with the system all shut down? The "equalized" pressure with the system shut down, engine off and all parts cooled to ambient will still vary directly with the ambient temperature.
Having said the above, I strongly suspect your TXV. On the "L" units, it is very easy to damage the temperature sensing bulb. As a quick test, peel back your cork tape and try to use a hair drier or heat gun to heat up the temperature sensing bulb while a helper watches pressures and vent temps. This will only reveal a calibration problem. If the bulb and TX valve are bad, then nothing will change.
My quickie math suggests to me that you have a total of 7 oz of PAG oil in your system. If improperly placed (eg: lots of oil at the TXV), this could make your TXV react poorly and/or slowly.
Did you install your condenser and liquid line so that the hose from the compressor is connected to the upper condenser outlet and the hose to the Receiver Drier is connected to the lower condenser outlet? This is important to ensure that only liquid (albeit high pressure) refrigerant goes into your rec/drier.
If the hoses/condenser orientation are correct, the the problem is definitely related to the TXV.
On the plus side, you appear to have a system with no leaks and your compressor is good, as indicated by the ability to pull 22 psi on the suction side and put out 275 on the discharge side. For what it is worth, if your ambient temps were high and your box fan is not very powerful, it is possible that you only needed to add some more RedTek to get more cooling. My system uses and orifice tube instead of a TXV, so YMMV, but I think that you will generally want to see 28 to 30 psi on the low side before concluding, definitively, that the TXV is bad. Depending on the ambient temp, 275 psi on the high side is not totally out of range.
I usually test with the vehicle interior closed so that the closed-loop system gradually removes heat from the interior. This will gradually lower the high side pressures. You might also consider hot-wiring your rad fan on in addition to the box fan. I used thick adhesive-backed foam to seal the condenser to the radiator so the rad fan more effectively pulls air through the condenser.
My system has slightly less volume than a normal VW system owing to a very compact evaporator, but I still needed very close to three cans of RedTek to optimize performance. My anti-ice-up thermostat keeps mine from producing vent temps lower than about 42F to 44F, but adjusting or disabling that would get me down to the mid 30's. RedTek works!
Do not fret - - leaks and bad compressor are the expensive and ornery problems. TXV is not so difficult to replace. You will get there!!
_________________
'86 Syncro Westy SVX |
|
| Back to top |
|
|
dhaavers
Samba Member
Joined: March 19, 2010
Posts: 7757
Location: NE MN (tinyurl.com/dhaaverslocation)
|
| Posted: Tue Jun 09, 2015 9:32 pm Post subject: Re: Red Tek real time help... |
|
|
| markz2004 wrote: |
| ...you put the redtek into the wrong side of the system. |
Umm, no. I just saved a little time on the first can... 
Thanks for checking in, Howie...here's what I remember...
- Ambient temp while charging was about 80F...
- Condenser hoses correct...from compressor directly to top of condenser; bottom of condenser to R/D & then exp.valve...
- I did have the hatch and engine cover open...
- The box fan is a cheap plastic model, but it's what I had...
After your input & some other searching, I'll try a few things to fine-tune this tomorrow:
- cover the engine & shut the hatch...
- in place of the wimpy box fan, I'll run the garden hose with a mist of cold water on the condenser...
- keep the rad fan on (it comes on whenever the compressor runs)...
- go for a drive to see what I get on the road (closed interior, faster ram air & higher rpm's)...
...anything else...???
_________________
86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS> |
|
| Back to top |
|
|
Terry Kay
Banned
Joined: June 22, 2003
Posts: 13331
|
| Posted: Tue Jun 09, 2015 9:38 pm Post subject: |
|
|
NEVER introduce the freon into the high side for any reason, at any time, regardless what somebody has told you, or what you may assume.
Period.
But--that being said, and what you have done--I'll tell you what it probably is-
The aftermarket expansion valve from your favorite vendor--
It ain't the same, it won't work, and your not the only guy that has had big pressure readings on the high side with a low volume of refrigerant in the system.
I don't know what CFM your vacuum pump is, or what it's capacity might be--
Some of the newer pumps won't pull all of the moisture out of the system in 4 hours--might be this.
But with that 275 reading, you have either a restriction somewhere, too much moisture still in the system or that expansion valve isn't working right.--being an aftermarket, non -OE item.
Seen this happen a bunch.
_________________
T.K. |
|
| Back to top |
|
|
nevadaesh
Samba Member
Joined: May 08, 2013
Posts: 214
|
| Posted: Tue Jun 09, 2015 11:04 pm Post subject: |
|
|
Dave, good luck with your charging of the system. I hope you don't mind my post, but I'm fairly frustrated with trying to get my AC working properly like you. I don't want to hijack your thread but I have to comment and ask some questions.
I have read several threads where pressures have not been correct and one of the culprits mentioned is the expansion valve. And most all of the posters say they put in new valves.
So, is it potluck on getting a good valve when you order a new one? Is there anyway to test the valve before you put in the rig? I know mine is a PITA to install and remove. So when you put in a couple of cans of RedTek and find you have a bum valve, you then have to vent the system to put in another suspect valve and start all over.
Do all you DIYers have evacuation machines that you can save what you put in?
So I bought my new expansion valve from either GW or Van Cafe so here is the really dumb question - where do you get a "real" expansion valve that is not going to be suspect?
_________________
'85 Westy
'07 FJC
'02 Camry |
|
| Back to top |
|
|
djkeev
Samba Moderator
Joined: September 30, 2007
Posts: 32625
Location: Reading Pennsylvania
|
| Posted: Wed Jun 10, 2015 2:56 am Post subject: |
|
|
| nevadaesh wrote: |
Dave, good luck with your charging of the system. I hope you don't mind my post, but I'm fairly frustrated with trying to get my AC working properly like you. I don't want to hijack your thread but I have to comment and ask some questions.
I have read several threads where pressures have not been correct and one of the culprits mentioned is the expansion valve. And most all of the posters say they put in new valves.
So, is it potluck on getting a good valve when you order a new one? Is there anyway to test the valve before you put in the rig? I know mine is a PITA to install and remove. So when you put in a couple of cans of RedTek and find you have a bum valve, you then have to vent the system to put in another suspect valve and start all over.
Do all you DIYers have evacuation machines that you can save what you put in?
So I bought my new expansion valve from either GW or Van Cafe so here is the really dumb question - where do you get a "real" expansion valve that is not going to be suspect? |
Some good questions ^^^
I cannot recover refrigerant at hone.
I too have noticed this Expansion valve Phenomenon!
Can good parts no longer be purchased? Are we subject to an ever increasing supply of Crap?
While I have spent $$'s on a new Expansion Valve, I am tempted to simply clean mine and leave the new one in the box!
Dave is Way ahead of me and am sorry for his troubles.
Dave
_________________
Stop Dead Photo Links how to post photos
Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473
Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537
Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert |
|
| Back to top |
|
|
djkeev
Samba Moderator
Joined: September 30, 2007
Posts: 32625
Location: Reading Pennsylvania
|
| Posted: Wed Jun 10, 2015 3:33 am Post subject: |
|
|
Good Morning Dave!
Bet you slept well last night? 
First off........don't be rattled by the OMG!!! You put refrigerant in the High Port?!? You will surely die! Comments.
If the system were running, yes, you could over pressurize and explode the can in your hand!
But, the engine was off, a full vacuum was pulled, it is actually a recommended procedure when filling with R12a to let the system suck in R12a putting a precharge into the compressor. It is also a method to check for a stuck closed Expansion Valve before starting the engine.
However....... Todays public safety announcement .......
NEVER RUN THE COMPRESSOR WITH A CAN ATTACHED FEEDING INTO THE PRESSURE PORT!!!!!
You are likely over charged or overheating..... Or as TK said.... Sucky Expansion Valve.
I Didn't know that you frozen Northern folk even had 80* days!
Hychill is an R12a company down Under in the Land of OZ. They Put out some fantastic literature.... Unlike our North American R12a friends..... 
I have a group of Kiwi's in my guest quarters for the Summer.... Should see what they know?
Follow this link, print it out and put it into your Bentley, but start at page 16 and figure out what may be wrong. At worst it's a bad valve. Not the end of the world. A true PITA but you will get through it.
I had this linked in the RedTek thread but Hychill moved it.... Go figure.
I just updated the link.
I also just finished printing out the manual. The link being moved was very disconcerting and I Like hard copies of such things! Into my Bentley 2.0 it goes!
http://hychill.com.au/content/3-info/hychill-manual.pdf
At least you have some morning reading literature today!
Dave
_________________
Stop Dead Photo Links how to post photos
Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473
Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537
Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert
Last edited by djkeev on Wed Jun 10, 2015 4:28 am; edited 6 times in total |
|
| Back to top |
|
|
tpinthepack
Samba Member
Joined: July 11, 2004
Posts: 816
Location: clearwater,florida
|
| Posted: Wed Jun 10, 2015 3:44 am Post subject: |
|
|
Do you guys know if the later style Expansion Valve that is shaped like a square block of alloy is also junk from Four Seasons? I don't want to hijack thread either, but I am at the same stage as Dave right now so this thread has my interest.
Tony
_________________
TP in the Pack (I am a cyclist)
1968 Manx N.O.S. w/ Barrett Chassis
1960 Single Cab 1914 w/ 40 DLRA's
1990 Vanagon DOKA
1972 Super Beetle
1979 Super Beetle Convertible
2011 Porsche Cayenne |
|
| Back to top |
|
|
morymob
Samba Member
Joined: November 09, 2007
Posts: 4683
Location: east-tn
|
| Posted: Wed Jun 10, 2015 4:27 am Post subject: |
|
|
| Don't look to be overcharged at all. The block style was, maybe still used by earlier chrysler minivans, had one go bad but a simple device. Just my way of doing things, todays questionable parts, but after cleanout u can 'bench test' orig expansion valve to see if it does open/close, of 5 i was able to use the original ones,i think trying at least u have at least a 90%chance . This has applied to the brand'X'ones too. Even being on the old side i still have more confidence in orig german parts over this newer stuff, my2cts, as usual no warranty offered at this time. Never needed more than 3 cans of red tec. |
|
| Back to top |
|
|
djkeev
Samba Moderator
Joined: September 30, 2007
Posts: 32625
Location: Reading Pennsylvania
|
|
| Back to top |
|
|
Terry Kay
Banned
Joined: June 22, 2003
Posts: 13331
|
| Posted: Wed Jun 10, 2015 6:41 am Post subject: |
|
|
You have a sight glass on the dryer?
You see bubbles, or is it clear?
Is the lines frosting up?
All indications are leading to s stuck open expansion valve, possible restriction in the dryer, possible some air & moisture remaining in the system.
_________________
T.K. |
|
| Back to top |
|
|
|
