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Garage => Mechanicals => Topic started by: 1980sdga on 29 June 2011, 07:50 PM

Title: Parallel flow condenser
Post by: 1980sdga on 29 June 2011, 07:50 PM
I'm in the process of fitting a parallel flow condenser (16" X 20") and a Sanden 709 compressor.  Anyone done anything similar?

This is turning into a Can-O-Worms  ;D
Title: Re: Parallel flow condenser
Post by: jbrasile on 29 June 2011, 08:58 PM
Jon, you are on the right track. You may run into a little bit of trouble getting a bracket that would work with the Sanden but I am sure one can be fabricated.

Let us know how it goes, this mod could benefit a lot of us wanting to improve the efficiency of our a/c system.

Tks,

Joe
Title: Re: Parallel flow condenser
Post by: 1980sdga on 29 June 2011, 09:12 PM
I actually ordered a York to Sanden bracket to use as a starting point for building a bracket.  I can't tell exactly what I'm going to do until the compressor gets here tomorrow.

I've seen OM617 brackets for Sanden compressors so I know it will fit in the space. The oil cooler lines may get in the way though...
Title: Re: Parallel flow condenser
Post by: WGB on 29 June 2011, 09:19 PM
This is probably a necessary mod for the 280/300 guys so will be interested in how it goes.

Please post pictures.

Bill
Title: Re: Parallel flow condenser
Post by: 1980sdga on 29 June 2011, 10:12 PM
The only thing that bugs me is that it'll be smaller by 40 square inches and I don't know what the volume differences are.

Cool picture:

(http://i711.photobucket.com/albums/ww112/jhoff/condensers.jpg)

The first two are tube/fin like We have, the third is a "serpentine" and the far right is a parallel flow.  I've never held either but I think a parallel flow has header tanks on either side, whereas the serpentine is like the tube/fin with different shaped tubing.

It would be interesting to know the volume differences.  Since my compressor has the same displacement per revolution as the old R4 this would be the only big change in the system volume-wise.

Interesting that with an R4 it seems to be recommended that oil be dispersed throughout the system when it's assembled but the Sanden just requires the compressor to be filled. It still recirculates  but the Sanden must not be as sensitive to oil volume as the R4.

I will say that removing the old condenser was more work than I anticipated  :o
Title: Re: Parallel flow condenser
Post by: 1980sdga on 30 June 2011, 05:04 PM
Just some pictures of my compressor mock-up.

This is pretty close to where it will end up:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2338.jpg)

I believe I can weld onto the bracket and use the lug that runs parallel to the crankshaft for one mounting point. And use the lug beneath it (with the bore parallel to the cylinder bores) for another.

Top view:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2337.jpg)

Thankfully it doesn't look like it will interfere with the cooler lines  :D  I am going to have to pull them all the way out though  :P  There just isn't enough room to work in there with them in the way...

So far I haven't ran into any big obstacles.

Where I am now:

(http://i711.photobucket.com/albums/ww112/jhoff/mod.jpg)  weld

(http://i711.photobucket.com/albums/ww112/jhoff/weld1.jpg)

The yellow shows where the parts will need to be welded.  Gotta scrub the engine some more...
Title: Re: Parallel flow condenser
Post by: WGB on 01 July 2011, 02:48 AM
Looking Good.

Bill
Title: Re: Parallel flow condenser
Post by: 1980sdga on 01 July 2011, 08:47 PM
So far it's looking like it'll be relatively easy to pull off  :)
Title: Re: Parallel flow condenser
Post by: KenM on 02 July 2011, 05:17 AM
Interesting Jon, what made you abandon the R4 replacement, did I miss something in your other post? No need to bother with putting oil in any other part of the system with any compressor, the oil will circulate around the

system and come back to the comp in good time. The new condensors are much more efficient space wise and it should be a nice modification, the only drawback with the aluminium is that it's so easily holed, make sure it's nice

and secure so no rubbing occurs.

Look forward to more progress reports. Cheers,
Title: Re: Parallel flow condenser
Post by: 1980sdga on 02 July 2011, 09:41 PM
Some pics. of mocking it up after getting the compressor mounted in the bracket. More on the bracket later

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2342.jpg)

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2343.jpg)

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2344.jpg)

I clamped those steel bars to the crank pulley to line everything up. I had the wood clamp on the compressor/bracket assembly to use as a "handle" to position it. It was resting on the floor jack so I just raised/lowered it and kept shimming the "handle" with wood until it was in position.  It was like playing Jenga a couple of times  ;D

With jigs removed:


(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2345.jpg)


(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2346.jpg)

In the last pic you can see how I had to use 2 bolts on the tensioning slot. The pivot point is a through bolt on the bottom. I had the slider part made up with a through bolt and a spacer between the "ears" but the compressor didn't want to slide for adjustment. Plus it would have to squeeze the compressor ears to tighten it down.

The bracket I used is supposed to be a York to Sanden adapter but it's really more of a kit because it needed quite a bit of work to get the adjustment slot working using a single long bolt for the pivot.

The compressor is a mid 80's 709 from a Hyundai Elantra  :o  It's a Four Seasons reman.

I gave up on the R4 because they seem to have a poor reputation for durability. It may just be that folks damage them during charging and start a snowball with failed compressors from previous crud in the system.  Anyway, the stories have me spooked, plus my old R4 was cooling fine but it was noisy. I also just do stupid stuff sometimes  :D

I'll be sure to make sure I don't have any rubbing going on when I get around to the condenser.

I sure hope this works...

Here's the bracket I started with:

(http://i711.photobucket.com/albums/ww112/jhoff/bracket.jpg)

The instructions had it using 4 separate nuts and bolts on 4 of the compressor ears.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 03 July 2011, 12:30 AM
Quote from: 1980sdga on 02 July 2011, 09:41 PM
Some pics. of mocking it up after getting the compressor mounted in the bracket. More on the bracket later

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2342.jpg)

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2343.jpg)

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2344.jpg)

I clamped those steel bars to the crank pulley to line everything up. I had the wood clamp on the compressor/bracket assembly to use as a "handle" to position it. It was resting on the floor jack so I just raised/lowered it and kept shimming the "handle" with wood until it was in position.  It was like playing Jenga a couple of times  ;D

With jigs removed:


(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2345.jpg)


(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2346.jpg)

In the last pic you can see how I had to use 2 bolts on the tensioning slot. The pivot point is a through bolt on the bottom. I had the slider part made up with a through bolt and a spacer between the "ears" but the compressor didn't want to slide for adjustment. Plus it would have to squeeze the compressor ears to tighten it down.

The bracket I used is supposed to be a York to Sanden adapter but it's really more of a kit because it needed quite a bit of work to get the adjustment slot working using a single long bolt for the pivot.

The compressor is a mid 80's 709 from a Hyundai Elantra  :o  It's a Four Seasons reman.

I gave up on the R4 because they seem to have a poor reputation for durability. It may just be that folks damage them during charging and start a snowball with failed compressors from previous crud in the system.  Anyway, the stories have me spooked, plus my old R4 was cooling fine but it was noisy. I also just do stupid stuff sometimes  :D

I'll be sure to make sure I don't have any rubbing going on when I get around to the condenser.

I sure hope this works...

Here's the bracket I started with:

(http://i711.photobucket.com/albums/ww112/jhoff/bracket.jpg)

The instructions had it using 4 separate nuts and bolts on 4 of the compressor ears.

Ken, my compressor says it has "100 VIS PAG" in it and it says compatible with both R12 and 134a.  I'll actually have both type of valves on the system when I get it together  :o  so I guess I can go with either?
Title: Re: Parallel flow condenser
Post by: Squiggle Dog on 03 July 2011, 02:10 AM
This is great! I will for sure need working (and efficient) air conditioning the next time I drive down south or move somewhere warmer. I'm also going to be doing the manual heat conversion fairly soon, so I should work on the air conditioning at the same time.

It's always nice when someone goes ahead and experiments with things first. This way I can learn from your mistakes instead of my own!

It's looking good, though. I also have to add that I much prefer the location of the compressor on the W116 300SDs versus the W110 200Ds with the compressor and bracket getting in the way of almost everything in front of the engine, making even adjusting the alternator belt difficult!
Title: Re: Parallel flow condenser
Post by: 1980sdga on 03 July 2011, 01:08 PM
Check this out Squig:

http://www.oldairproducts.com/catalog/heater-cores/50-1555/heater-valve-p-3667.html

May give you some heater ideas. 

If this compressor project works out then it could be duplicated with a welder and some basic steel stock.
Title: Re: Parallel flow condenser
Post by: Squiggle Dog on 03 July 2011, 06:34 PM
I got a manual heater valve from Mercedes-Benz that is a direct replacement for the ones with manual heat, and it was only $20 and came with the vacuum pod for opening and closing.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 03 July 2011, 08:12 PM
Quote from: Squiggle Dog on 03 July 2011, 06:34 PM
I got a manual heater valve from Mercedes-Benz that is a direct replacement for the ones with manual heat, and it was only $20 and came with the vacuum pod for opening and closing.

Cool. Don't you have ACC?
Title: Re: Parallel flow condenser
Post by: KenM on 04 July 2011, 12:53 AM
You're right about the oil Jon, if you have PAG already then you can go with either refrigerant, remember to flush the system if you are changing from mineral though (think you already had 134a from memory).

Thinking back to your pic of the grungy filter/receiver I'm sure you will notice much improved performance whichever way you go.
Title: Re: Parallel flow condenser
Post by: Squiggle Dog on 04 July 2011, 02:17 PM
Quote from: 1980sdga on 03 July 2011, 08:12 PM
Cool. Don't you have ACC?

I've removed some of the components of the ACCII and at some point will have a fully manual system.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 04 July 2011, 07:11 PM
I really like the looks of the manual system. It just looks more like it belongs there than the ACC. I would like to experience the manual controls though. I've read that it works well.

I would also like to experience a working ACC system  :P  Mine was working 100% about 10% of the time  ;D 

My system was converted to 134a in 2001 according to the sticker and it was cooling pretty well when the flippers and flappers were working and the heater valve wasn't open  ::)

The service records show that it was recharged about every year and you guys saw my drier guts. I'm hoping new hoses will help with the leaking if I can assemble them properly  :o

How many cars had ACC and an R4 that were sold outside the US?  Seems like the Euros got most of the Sandens.
Title: Re: Parallel flow condenser
Post by: jbrasile on 04 July 2011, 11:09 PM
Jon,

R-4's as far as I know were exclusive to OM617 engines.

Most euro's prior to 86 have York on 6 cylinder and diesel powered cars and A-6's on the V8-s

Starting in 86 you will see either Sanden or Nipodenso across the board. Some mid to late 80's cars equipped with M110 engines also got Sanden

The manual a/c system when working properly is far superior to ACC in all respects and having full control of temperature and air flow is just so much better.

Tks,

Joe
Title: Re: Parallel flow condenser
Post by: 1980sdga on 05 July 2011, 11:34 AM
Thanks Joe. That explains why all the 617 info (Including 126's, which are common here) is about R4's. There may have been some sanden brackets for 617's but I believe they were aftermarket and they seem to be awfully rare!
Title: Re: Parallel flow condenser
Post by: 1980sdga on 05 July 2011, 08:24 PM
Some quick pics of the new condenser:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2363.jpg)

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2362.jpg)
Title: Re: Parallel flow condenser
Post by: 1980sdga on 07 July 2011, 07:22 PM
Looks like it will work!  This is still mocked up with none of the hoses crimped or anything. I still need to make a bracket for the cooler lines near the compressor but I'm VERY happy that it'll work with the stock cooler lines:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2373.jpg)

Here's a mockup of the condenser:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2376.jpg)

Kind of gives an idea of how much room is needed for the end hoses. They take up a lot of space  :o

I'm actually planning on taking Bolbols idea to the next level. He said he had good results with a similar compressor and an orifice tube. I figure a P-flow condesner can't hurt.

Any input on this one?

What do you think Ken?  Am I insane  :o



Title: Re: Parallel flow condenser
Post by: KenM on 09 July 2011, 02:01 AM
Hey Jon, in your first pic it looks like you won't be able to get a gauge onto to the discharge access fitting, unless it's the angle of the pic. Unless the condensor has internal channelling, having a receiver/drier will be important

otherwise you might find that you get flashes of vapour in the liquid line. Personally I wouldn't be in too much of a hurry to change to a fixed orifice type expansion mechanism, it's old technology from before tx valves became

much better. Whichever system you use, you can (should) only deliver as much refrigerant to the evaporator that can be successfully evaporated before it leaves the evap, otherwise you are asking for liquid floodback to the

compressor. With a fixed orifice the correct refrigerant charge of the system will probably become much more critical for this reason and with the variable flow nature of a vehicle a/c system due to compressor speed

fluctuation and variations in internal heat load the chances of flooding would increase. You would need a decent accumulator in the suction line to accommodate these factors. If your tx is adjustable you should be able to get

the superheat right down to 2 - 4k which will provide maximum cooling with less risk of flooding or oil return problems.

Just my $0.02.   
Title: Re: Parallel flow condenser
Post by: 1980sdga on 09 July 2011, 03:58 AM
Thanks Ken. I'm not past the point of no return yet  ;D

The condenser has about 6 compartments in each tube. I looked inside to check and you can see them divided up. The tubes must be extruded aluminum.

It's just really different technology from the old one.  The volume I'm losing kind of bothers me. No receiver either...

I wonder if the new style condenser is that much more efficient than the old one?

Going to an orifice tube from an expansion valve  really just changes the volume of liquid for the volume of gas, right?  I was thinking about using a big GM accumulator like GM systems use to keep any liquid from reaching the compressor. 

Are there specific parameters for the high and low side pressures to go by when charging?  (I am having a professional vacuum the system and charge it if I ever get it done :o)

I have ordered a hose crimper, and I needed new hoses on my old system so If it doesn't work out well I can re-install the expansion valve. It'll add about $150 to the project to try this and it's interesting to fool around with.  I am going to test out the system before putting the instruments and all back in!

The mechanicals and all look OK. I still need to build an oil cooler line bracket above the compressor and all the access fittings have clearance.  It's hard to get a good angle on the pics because it's so low on the engine.  Making sure everything would fit and still be accessible was my biggest worry!

Thanks again for the help Ken! Your descriptions really gives me a better understanding about how these systems work.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 09 July 2011, 11:50 PM
Put a bigger fan on it. 16" vs the original 12". I got it at Advance auto and it's about the biggest fan that I could find that would fit in there.

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2382.jpg)

I'm hoping it'll help the condenser work the way it should.

Done with this part:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2387.jpg)

I modified and re used the old aux fan mounts.  It's not that loud and moves a lot of air through the condenser.
Title: Re: Parallel flow condenser
Post by: KenM on 11 July 2011, 02:56 AM
Looking very professional Jon, nice work I'd say. That style of condensor is much more efficient than the tube type, it simply comes down to surafce area and the internal surface area is much larger than the old style ones,   

which is why your new one is so much smaller. A receiver/ drier will be a must in the system and definately get an accumulator if you are going to the fixed orifice type setup. Sounds like your weather is similar to ours here, in

reverse of course. We get filthy humid summers and lovely clear warmish winters usually, been a fantastic winter here this year so far. Not sure what you mean by 'Going to an orifice tube from an expansion valve  really just

changes the volume of liquid for the volume of gas, right?'  Both of them are simply a means of changing a high pressure liquid to a lower pressure liquid/vapour mixture so that it can evaporate in the evap and absorb heat.

The difference is that the fixed orifice is going to continue to hump refrigerant into the evap whether it's evaporating fully or not, whereas the tx will sense that it's cold enough (actually works around pressure not temp) and

close off accordingly. You will have to play around with the charge in the system in order to get it right, I imagine you might need to drop in a bit more oil too to compensate for the accumulator. The important thing will be to

check the superheat at the compressor, the fella charging it for you should know all that.

Looking forward to seeing the results. 
Title: Re: Parallel flow condenser
Post by: 1980sdga on 11 July 2011, 12:50 PM
Thanks Ken! 

What I meant by "Going to an orifice tube from an expansion valve  really just

changes the volume of liquid for the volume of gas" is that:

TXV- uses a receiver which stores LIQUID refrigerant in order to ensure that the TXV has enough liquid to keep the evaporator flooded Kind of an extension of the condenser.

OT- uses an accumulator which stores GAS refrigerant which I guess is just an extension of the evaporator and ensures that the compressor has enough gas and doesn't get any liquid.

TXV- uses the valve to "throttle" the gas through the evaporator

OT (CCOT)- uses the compressor switching on/off to throttle the gas through the evaporator.

I'm trying to learn this stuff (Mainly for the heck of it) and I appreciate your input!

Here's my oil cooler line bracket:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2388.jpg)


I'm anxious to get it together and fire it up!
Title: Re: Parallel flow condenser
Post by: 1980sdga on 13 July 2011, 07:51 PM
(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2401.jpg)

Here's my accumulator. It fit nicely into the spot where my cruise control servo was. I'll have to permanently move it if this works.

I also started working on mounting the receiver:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2404.jpg)

Title: Re: Parallel flow condenser
Post by: KenM on 14 July 2011, 04:51 AM
Looking good....
Title: Re: Parallel flow condenser
Post by: bolbol on 16 July 2011, 12:41 PM
Jon, you are doing a beautiful job. I have couple of observations. With Orifice Tube system, the receiver/dryer is replaced by the accumulator. When I did my system, I took out the receiver/dryer and custom fit a connection piece after the condenser and just installed
the Pressure and temperature switches on this piece,, those are usually installed on the receiver/dryer in the original setup.

(http://gallery.w116.org/dl/30104-2/IMG_0020.JPG)

I tried to research the outcome if I kept the receiver/dryer and accumulator at the same time. I got no direct answer from anyone who is experienced in Auto/AC. Just the typical answer , "OT uses accumulator and TXV uses receiver/dryer" 

Ken, any input ?

Jon, in my opinion I see no reason why your setup will not work. The receiver/ dryer will work as an extra filter,reservoir and it Will do a better job at drying and filtering than an accumulator.  your high pressure side may get little higher, but it should not be a problem at all.

Now, with regards to the temperature and pressure switches, are you saying you did not have those originally ?

One more thing, with your Parallel flow condenser and fan installed, you might notice that coolant temperature will get higher, but I don't think you should  worry about it.

Bolbol

Title: Re: Parallel flow condenser
Post by: bolbol on 16 July 2011, 01:29 PM
Jon, I don't know if I was clear about the cycling switch, In the original set up, as I indicated before, the temperature probe "sensor" which is installed in the evaporator, will cycle the compressor when the evaporator has reached the set temperature, you should also have this already installed in your evaporator. This has worked for me as  the compressor cycling switch. In a typical Orifice Tube system, they install a pressure or temperature cycling switch on the accumulator itself. I see no need for going this direction specially if you are going to install the original pressure switch on the receiver/dryer, my original pressure switch which I installed on the connection piece as I said before, has a dual function. It will switch off the compressor if there is low refrigerant level or no refrigerant in the system, or if the pressure is too high.

Walla, as I stated before, our w116 are already prepped  for a relatively easy switch to Orifice tube.

If you want to have a typical OT system with a cycling switch on the accumulator, I will work with you to accomplish that,, but in my opinion , there is no need.

bolbol
Title: Re: Parallel flow condenser
Post by: 1980sdga on 16 July 2011, 07:24 PM
Thanks bolbol!  I'm basically trying to replicate your system and hope it works here in the hot humid southern US!  How exactly does the evaporator switch work?  Does it have an on/off parameter that turns the compressor back on once the evaporator warms a little? How often does your compressor cycle?  I have the ACC system and it has the temperature switch on the evaporator.

I also used #6 hose between the condenser and evaporator and the OT holder is a larger diameter. Looks like you used #10 hose?

Here's a picture of the holder I put together:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2406.jpg)

You can see how the hose diameter is actually smaller than the tube. I'm not sure if this narrowing will have any ill effects  ???

I too looked into running both a receiver AND an accumulator and got about the same answers you did so I figured I'd try it out.  I already had the part.

Thanks again for the inspiration to do this!

Jon

Title: Re: Parallel flow condenser
Post by: KenM on 16 July 2011, 08:33 PM
Hey guys, a few observations from here: first off I can't see any operational penalty in having a receiver/drier in the system as well as an accumulator. Bolbol's replacement solution looks very neat but are you saying you have

no filter or drier in your system bolbol? An accumulator provides no filtering or drying of the refrigerant and it would be most advisable to have a filter/drier in the system with an orifice tube, without necessarily having the

receiver function as well. I can't see why having a new type condensor would lead to higher liquid temps or pressures, as long as it is sized to suit the other components it will work just as well as any other condensor.  Jon,

you will still need the safety switches as bolbol says. Cycling the compressor off the thermostat in the cabin shouldn't be a problem, one thing to watch out for here is that it doesn't cycle on too soon after having switched off.

The compressor will not like starting again if the high side pressure is still at or near it's operating pressure, the system must have enough off time for the pressures to equalise or at least get somewhere near equalising,

otherwise the starting torque required will be way too high. This time will depend on conditions but I imagine you would need at least 60 seconds off time to allow pressures to approximately equalise. Can't see your hose

diameter coming into the orifice being a problem Jon, all looks good there. 

Keep going, looks good!!
Title: Re: Parallel flow condenser
Post by: bolbol on 17 July 2011, 02:00 AM
Jon, please look at 83-542 in the Library, it lists specification and parameters for the temperature switch. In picture 183-8767 please take note of the switch and figure "3" the thermostat that goes into the evaporator.

Ken, with all respect, the Accumulator I fitted does have Desiccant and screen for filtering and drying, but I agree with you that a receiver does a better job at that, I will fit either an in-line filter or install a receiver/dryer next year,, awaiting the outcome of Jon setup.

Regarding higher temperatures of coolant, I just know from experience that the parallel flow condenser and the larger electric fan might block some of the air sucked in by the engine fan and will counter effect the flow of air marginally,, I just wanted Jon not to be allarmed if he sees higher temps.

Another note of interest, I am running at 20-30 PSI low side and 150 PSI  high side,, at 28C  , RPM at 1700.

Bolbol
Title: Re: Parallel flow condenser
Post by: KenM on 17 July 2011, 04:30 AM
Quote from: bolbol on 17 July 2011, 02:00 AM

Ken, with all respect, the Accumulator I fitted does have Desiccant and screen for filtering and drying,


Ah ok, I stand corrected. I think (hope) I said somewhere before that it's been a while since I did any vehicle a/c. I haven't heard of a beastie such as this but it sounds like a good idea. Which refrigerant are you running

Bolbol? Your figures sound pretty good for r12. Interesting to hear your experience of a slight air flow restriction with this style of condensor, do you think that it's simply down to the higher density per face area of the fins?

Cheers,
Title: Re: Parallel flow condenser
Post by: 1980sdga on 17 July 2011, 09:00 AM
Thanks for the input guys!

My car has ACCII which doesn't have the dash mounted temperature switch. It does have an "ETR" (Evaporator Temp. Regulator) in the compressor circuit which turns the compressor off at 36F.  I can't find anything about how/ or if it turns the compressor on when temps rise  ???

It is also quite inaccessible  ::)  requiring dash removal to change  :o  It's right beside the center vent vacuum pod...

I have isolated the wires that run to it and there are lots of evaporator temperature switches available so maybe I could leave the original in place and retrofit another one?  Maybe one that turns the compressor OFF at 34F and back ON at 38F?  I would have to figure out how to fish the capillary tube into the evaporator somehow.

Maybe my existing ETR will be fine.

About the accumulator. Most older US cars that I'm familiar with (Actually trucks, with COLD AC) use an OT and accumulator and they don't run receivers. The standard GM accumulators have filters and dessicant in them.  I just decided to put the receiver on my system because I had it and it would make it easier to change back to TXV if I had to and the consensus is that it'll work. It is uncharted territory though  :D

Good point on cycling the switch too soon Ken!  I hadn't thought of that but I understand what you mean.

Just kind of anecdotal but...

I was fooling with the condensers and the new fan and it did seem like there was more airflow through the old condenser and the new one.  Not very scientific but just by "feel" it seemed that there was more air moving through the old one.

Thanks again for the help guys!  I've never even fooled with auto AC systems so I need all the help I can get  :o

It's mostly faith and wrenches...

I had to move the condenser an inch and a half towards the left in the pic. The fan is in the same location.

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2410.jpg)

I didn't like the receiver sticking out so much.

Previous location:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2404.jpg)

The condenser is now a lot more centered with the radiator.



Title: Re: Parallel flow condenser
Post by: bolbol on 18 July 2011, 02:28 AM
Ken, I was running r12 at some point before, and I was curious to run R134a because of availability issue of r12. So now I am running r134a and I hardly can notice any difference in temperatures or pressures. I think the condenser and double fans I installed are doing an adequate job at keeping pressures low, and you are absolutely correct regarding the parallel flow condenser having higher density, fins, per square inch and I think PFC ads another source of heat to w116's copper radiators to deal with

PFC are aluminum which radiate heat better than copper, that's good, but this heat is pushed through the radiator, that's marginally not good. If you have a maintained cooling system, then running few degrees higher should not be a problem. (based on my experience of installing a PFC off an W146 S500 on a W116).

Jon, I have almost no experience on AC II, which you have, but if your vacuum switches and AC electricals are working properly, then the ETR should give an electric signal to the compressor to switch on and off (cycle) at the set temperatures.

Bolbol





Title: Re: Parallel flow condenser
Post by: 1980sdga on 21 July 2011, 03:25 PM
Finally getting the accumulator in place:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2435.jpg)

Still waiting on the #12 hose for the suction line from the evaporator.

I've had my accumulator open and I understand that it is bad for them but I didn't have a choice  ???

Any advise on this?  Should I go with a new one when I do the final connections?  Seems like a shame to throw out a never used accumulator...
Title: Re: Parallel flow condenser
Post by: KenM on 22 July 2011, 04:24 AM
Just make sure you get a good vacuum on the system Jon and hold it under vac for several hours, it should remove any moisture accumulated in the dessicant. It can also help to break a vacuum a couple of times and pressurise the system with dry nitrogen, helps to get a good final vac.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 07 August 2011, 06:35 PM
Finally got the hose crimper:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2494.jpg)


It seems to work pretty well. I have most of the hoses built but I need to make the hole in the firewall larger for the high pressure line to enter the cabin.

I've been working on this forever...
Title: Re: Parallel flow condenser
Post by: 1980sdga on 16 August 2011, 12:20 PM
I finally started her up today  8) 

Got the oil cooler lines fixed and routed, rad. in, etc. Now it's just AC stuff...

This was the hold-up:

(http://i711.photobucket.com/albums/ww112/jhoff/IMG_2504.jpg)

I used my AC hose crimper to repair my oil cooler line  ;D
Title: Re: Parallel flow condenser
Post by: 1980sdga on 29 August 2011, 05:11 PM
Did some testing today:

http://www.youtube.com/watch?v=KoBkf3xqH78

The low pressure was 30 psi and the high side was 200 psi at idle with 2 lbs of 134a.

I'm going to run it some more and check for leaks. Maybe add another 8 oz of 134?

I ended up using a .62 orifice tube but I may try a .072 and see how it works.

It did get down to 40 F when rolling so I'm happy  :D  Not super enthused but happy!

Any input?

Ken, Bolbol?
Title: Re: Parallel flow condenser
Post by: KenM on 01 September 2011, 06:41 AM
Hey Jon,

Nice work, and congratulations on sticking with it and getting a good result. Sounds like you are well on the way, 40f air off is pretty good I would think, the way we alway used to test them was open all the doors, stick the fan on high, stick a brick on the accelerator so you maintain about 2000 rpm or so and then check your pressures etc. Your high side needs to be a fair bit higher than 200, would think about maybe 270 or so at that speed from memory. Then check your air off temp and you can adjust the charge from there. You must make sure to check the superheat at the compressor to be sure you don't overcharge it, don't know how this would play out with an orifice tube assembly but normally you would want at least 2k of superheat at the comp to be sure you aren't flooding back. This will change too with revs and load within the car so check it when the car is cool inside as well.
Looks like you're nearly there, just in time for winter as you were saying earlier...he he
Title: Re: Parallel flow condenser
Post by: 1980sdga on 01 September 2011, 06:44 PM
Thanks Ken!  I was mainly just charging it to test for leaks and such and if all seems OK after a few weeks of running I'm going to vacuum the system and check the OT to see if the filter picked up any junk.  Everything is new except for the evaporator which I flushed.

I had a shop do the vacuum/charge and I didn't want to monkey around too much on their dime!

I plan on getting my own vacuum pump and a set of gauges for the future.

I'm not sure if I need to worry about superheat values with an OT because the accumulator is supposed to make sure all the refrigerant is vapor before it hits the compressor.  The accumulator sweats quite a bit and it's running about 45 F. 

How do I arrive at the superheat value anyway? And do I just check it at the compressor suction line with an IR thermometer?

  When you say "air off" what do you mean exactly?

Thanks again for the help! Your advise has helped me a WHOLE LOT with understanding how these things work!
Title: Re: Parallel flow condenser
Post by: KenM on 02 September 2011, 03:08 AM
Yeah the accumulator is supposed to hold any liquid refrigerant and prevent it from going down the suction line to the compressor as you say Jon, would still check the superheat to be sure. The way to check is take your suction pressure and then either use a pressure temperature chart or you might have a temp scale on the gauge face, so the temp corresponding to the suction pressure is the temp of the refrigerant leaving the evap. Measure the temp at the compresor suction inlet and you should have a higher temp by  a few degrees K (celsius), minimum  2 for safety. It will vary of course with engine revs, heat load and will be more likely to flood at lower load. You want a digital thermometer, or IR that will react quickly to temp changes. If you have a digital thermometer with a probe, place it at about 4 or 5 o'clock on the pipe because any liquid is likely to be at the bottom of the pipe and will be picked up by the thermometer, tape it on and cover with a bit of insulation to prevent any false signals from ambient temps. Air off means the air temperature off the cooling coil, as opposed to air on.
Good luck,
Title: Re: Parallel flow condenser
Post by: 1980sdga on 06 September 2011, 12:14 AM
Thanks. I still have some issues that bother me. The shop that vacuumed/charged it for me only held vacuum at 30 (Not sure the value  :P) for a few minutes.  They only charged me $55 so I didn't press the issue when they said it was OK...

I plan on getting my own vacuum pump and some gauges. I probably have about 400 miles with the AC running. Haven't needed it much as of late... Now that I've seen some "professionals" vacuum/charge a system I have a better idea about how to do it. I'll probably run it a few hundred miles and inspect the orifice tube, do a thorough vacuum and recharge. They measured in 2 lbs of 134a in 8 oz increments until it started cooling so I also have some volume numbers.

I'm not sure how often, or even if, the compressor is cycling going down the road. I don't think it has cycled too soon with the system still pressurized like you mentioned, Ken. I accidently manually cycled it too soon once and the belt gave a squawk before the compressor started. Probably don't want to do that too often! I was thinking about installing a temporary light that would come on when the compressor is engaged so I can see when/if it's cycling.

Here's a vid of me manually cycling the compressor:

http://www.youtube.com/watch?v=G2XnY8lmC2o&feature=mfu_in_order&list=UL

Cameras help me a lot when working alone  ;D

I'm working out some mechanical stuff now, making sure no hoses are chafing etc. I made sure the condenser isn't rubbing against anything like you suggested using sliced heater hose parts to prevent any chafing.

I was worried about the compressor bracket because it is home made but I think it's pretty solid. I need check all the bolts for tightness an inspect the welds.

Title: Re: Parallel flow condenser
Post by: KenM on 06 September 2011, 07:25 AM
Hey Jon, first off, if your system doesn't hold a vac then you have a leak, need to do a leak test before you vac it out. Second, it's impossible to get a vac of 30", the most you can get down to is 29.99995 or some such, so they either need to get better instruments or more likely were just looking at their gauges. You need a vac tester to be accurate and to be sure that it's holding, it should hold a vac without rising appreciably for at least a couple of hours if the system is tight. I think as Bolbol was saying earlier that your thermostat should not cycle the compressor on too frequently, as you found out they don't like it when you do though. Sound slike you're getting close to done.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 06 September 2011, 10:33 AM
I guess I worded it wrong but it held vacuum for several minutes without leaking down.  The first time they vacuumed it I found a leak and had to tighten a fitting which seemed to fix it. After charging they went all over it with a sniffer and all looked well.  I made sure they sniffed the area behind the instruments REALLY WELL  :D  It's just such a PITA getting in there to tighten stuff up!  Hopefully running won't cause any leaks.

I'm not sure if it says anything but when running at an ambient temp of 85 F the receiver was 125 F and the accumulator was 44 F.

I really appreciate the input! 
Title: Re: Parallel flow condenser
Post by: Big Tiny on 25 October 2011, 05:26 AM
Hello Jon,

Would like to know how this setup is going, really thinking I need to consider this same route.
I'm in QLD AUS, its getting hotter here, and the 76 280 is struggling to get cool.
Ive spent alot of time and cash on this at the local aircon shop, to no avail.

I'm starting to think the condensor is just no good with the R134A.

Brett
Title: Re: Parallel flow condenser
Post by: 1980sdga on 25 October 2011, 08:04 PM
Hey Brett,

My original factory setup was working extremely well before I did this work.  Unfortunately, here in the states we got R4 compressors which weren't the greatest to start with. r134a runs at higher pressures so it's just too much of a load on the compressor and they fail. I figured since I was changing out the compressor I'd make it easier to service the whole system by installing the orifice tube.

I had no complaints about the performance of the factory system and I'm in the southern US so the AC shop should be able to sort it.

I would start by making sure all your components are clean. The evaporator (The "radiator" in the car) needs to have clean fins and good airflow to work well. This goes for the evaporator as well. I'm sure cleaning the evaporator is often overlooked because it's so inaccessible.

What work was done to the car? 

I have a label on my car that has the oil and refrigerant volumes so I'll post them.

So far the rejiggered system is working well!  It started getting cool here so I'll have to give it some thorough testing next summer.
Title: Re: Parallel flow condenser
Post by: Big Tiny on 25 October 2011, 08:56 PM
Hello Jon,

Thanks for the reply.

Long story, short. The old M110 engine had a brand new compressor (York?), was flushed, new drier, charged R134 A, 1500 bucks later, still no good. Ac prior to that hadn't been functional for maybe 10 years, due to a seized compressor. I had Icy Cool come back and look at the car, they said everything was within "spec", total bull, it was useless on a hot day. You had to put windows down. A new condensor fan helped ( a little)

Now wind forward a few years, Ive now put a lexus V8 in her, along with, lexus 10PA denso compressor (NEW), we have now replaced the TX valve twice, re gassed 5 times ?.
Its running R134A, about 1 kilo, ac shop has tried, 750, 800, 1kg etc.

Now my only conclusion is the condensor is not up to the task, it is very clean (externally), radiator has been rebuilt, brand new 16 inch thermo, I tried two thermo's at one point, I think that wa slightly better so may go back to that at some point.

On the highway, at night after about 20 minutes, sitting on about 110, the centre vent wil pull down to around 6 degrees. Now that is on max cold, fan speed at lowest setting.
Generally during the day, it struggles to get under 10 degrees, and takes a while to get there, the side vents are closer to 20 degrees. Remember this is on the lowest fan speed, if you select the higher fan speeds, temp just goes skyward.

Just as a test, I just ran the car, and sprayed 50/50 water/meth onto the condensor, after about 5 min I was seeing 3.6 degrees at the centre vent. That was while stationary on the drive, about 25 degree outside temp. I really think this points to condensor efficiency at being on the very low side, its struggling (due to R134A ?) ( Dirty internally ? ). Now a new tube and fin might do the trick, but for the trouble its seems more logical to go with the newer parallel design, despite the few fitment issues.

I would really appreciate any input.

Regards,

Brett.
Title: Re: Parallel flow condenser
Post by: Big Tiny on 25 October 2011, 11:17 PM
I just phoned and MBV in NSW, and spoke with a chap there. He specifically said they run Hychill gas in all there Merc's, and that it runs more efficient than both R12, and R134A.

Has anyone had any experience with Hychill gas ?
Title: Re: Parallel flow condenser
Post by: 1980sdga on 26 October 2011, 10:04 AM
I don't know about alternative refrigerants...  My gut tells me just to stick with either r12 or r134a.  Our factory systems will work pretty well with 134a which is what I decided to go with. I think the only downside to 134a is that it works the system harder but this shouldn't be a problem with your new, updated compressor.

Here's a vid of my temp drop with a hot cabin at idle:

http://www.youtube.com/watch?v=KoBkf3xqH78

You should really start a thread on your Lexus powered 116  ;D  That sounds really cool  8)

It's a shame you've spent so much money and the AC still isn't working... Replacing the TX valve is a tough job and you've had it done twice!

It actually sounds like your heater is working at the same time as the AC, especially the higher vent temps at the outside registers. But it sounds like you have checked it out pretty well... I have ACCII (Or KlimaI, or Airtemp II depending on who you ask  :P) which "blends" warm and cold air to maintain temp. Maybe your system does something similar?

Did you check the side vent temps while spraying the condenser?  I'm mainly asking because a 10 deg difference sounds like a lot. My side vents run a little warmer but not that much Maybe 5 deg at the most.

I would hate to see you spend more $$ and sweat and still have a poor system. I would troubleshoot the entire heat/air system really well before throwing more at the compressor/evaporator/condenser part of the system.

I was also wondering if you had some type of bad failure that filled the system with debris from a bad compressor. This would foul the TX valve in short order even after a replacement and from what I understand, it's almost impossible to get it all out even with a good flush.  An orifice tube retrofit would allow for simpler/cheaper servicing in the future plus it adds another filter to catch debris. Plus a P-flow condenser can't hurt.

Good luck and keep us posted!
Title: Re: Parallel flow condenser
Post by: koan on 26 October 2011, 01:37 PM
Quote from: Big Tiny on 25 October 2011, 11:17 PM
Has anyone had any experience with Hychill gas ?

Yes, works well.

koan
Title: Re: Parallel flow condenser
Post by: 1980sdga on 26 October 2011, 06:17 PM
Is Hychill a propane based refrigerant guys?  Here in the states we get into issues with ozone/global warming/plague of locust preventing gas recovery machines that pro shops MUST use or face fines. All US cars have used 134a for about 20 years so most shops won't work with anything else because it contaminates the machines.

There are "alternative" refrigerants available here but they're mostly for do it yourself guys.
Title: Re: Parallel flow condenser
Post by: Big Tiny on 26 October 2011, 09:03 PM
Jon,

Yes the lexus conversion is worth a thread on its own  :D

The heater system has been bypassed to prevent dilution of the "cold air", My side vent temps, are probably closer to 7-8 degrees greater, but have only checked them a couple of times.

When I chilled the condensor with meth/water, and the vent temps went straight down to 3.6 degrees, about 3 min time lapse, I then assumed that the tx, evaporator etc side of things was working.

I also have a SC400, with identical engine, and ac compressor, so I know what they should do when working well, its really good for comparison. Now the only real difference between the two systems, is the lexus has a huge alloy parallel flow condensor, it really pulls down very quickly regardless of outside temp, they also run a massive hydraulic fan setup, that really shifts some air, probably twice that of the 16 inch electric I have.

I actually spoke with Hychill in AUS, his name is Ross, he put me in touch with a chap in Northern NSW, who has apparently been in the business 40 plus years, and swears by it. Anyway going to see him early next week, to get a diagnosis, and see what he thinks of the setup.

Oh just a side note, I managed to get the air vent temp down to around 5 degrees at idle yesterday, without the water/meth trick, took a while though. But thats what its does, it will get cool if you start the car and everything is cool, leave bonnet open etc. But take the car to the beach, let it get super hot, and then you have no chance, it aint going to get cold, windows down time. I don't have such a problem in any other car.

Koan, will hopefully I will have this gas in the car soon and see how it goes, have only read good things so far.

Brett
Title: Re: Parallel flow condenser
Post by: 1980sdga on 09 June 2012, 12:52 PM
I figured I'd update this since I've done some more work and it's getting HOT here in the Southern US.

I've had a little leak on one of the hi side hoses that which I FINALLY addressed. Re-crimped a new end on it and all seems well. I also changed orifice tubes from the Ford "blue" to a GM "white" which is what Bolbol used with his conversion.

So far so good!:

(http://i711.photobucket.com/albums/ww112/jhoff/SANY0010-1.jpg)

Ice in the engine compartment!  I think it's a little low on charge with only 24 oz of 134a but it's cooling about as well as my modern cars!

Went on a 100+ mile trip the other day and all seemed good to go.
Title: Re: Parallel flow condenser
Post by: Squiggle Dog on 09 June 2012, 01:48 PM
I am so glad that you are doing all of this work before me! I'm moving from Washington state to Arizona on July 1st (during the summer) and will need to get my air conditioning upgraded and working as soon as possible once I'm down there (as well as fully converted from automatic climate control to manual).

I plan to upgrade to a parallel flow condenser and Sanden compressor as you have and will run R134a. Let's hope I don't bake alive before I get operational air conditioning!
Title: Re: Parallel flow condenser
Post by: 1980sdga on 09 June 2012, 07:45 PM
These guys are supposed to have a Sanden bracket for our OM617's by the end of the month:

http://www.klimakit.com/product-o/

I'm interested in seeing it because you see how difficult it was mounting that SOB on my engine!
Title: Re: Parallel flow condenser
Post by: Squiggle Dog on 10 June 2012, 02:25 AM
Quote from: 1980sdga on 09 June 2012, 07:45 PM
These guys are supposed to have a Sanden bracket for our OM617's by the end of the month:

http://www.klimakit.com/product-o/

I'm interested in seeing it because you see how difficult it was mounting that SOB on my engine!

YES!
Title: Re: Parallel flow condenser
Post by: KenM on 10 June 2012, 08:57 AM
Glad to see it's still working Jon, yep if you have ice there she's a bit short, either that or you're flooding back something terrible, I'd be interested to know your running pressures and superheat readings

when it's all sorted properly.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 10 June 2012, 05:50 PM
Thanks Ken. I never did get any superheat readings  ???  I do have a pretty accurate thermocouple that I guess I could use.

After evacuating/ vacuuming/recharging I got 30psi lo and 150psi hi at about 2000 rpm. This was mid 80'sF and not real humid.  I'm guessing that I'm undercharged but it could be flooding as well. If you look at the picture the line closest to the engine is the return from the evaporator and the one close to the fender well goes straight to the compressor. Both are icing  :o

I went with a larger OT this time so I'm a little scared of over-charging and "slugging" my compressor!

I suppose I really need to get some superheat values to really know what's going on. Weird, no one ever worries about SH with accumulator systems but I've got a weird situation.

Any input?  You've been a great help!
Title: Re: Parallel flow condenser
Post by: KenM on 11 June 2012, 12:27 AM
You do need superheat readings to be sure you're not flooding back Jon, particularly if you have a larger orifice, (I can see why the use of the term OT now...) try to get a reading as close to the evap outlet as

possible and one at the suction inlet to the compressor for comparison. Your discharge pressure might be a tad low which could indicate a lack of charge, better to be sure though.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 23 June 2012, 09:21 PM
Well I added another 12 OZ of 134a for a total of 2 lbs and sorted out my blower problem. No more icing and it was cooling like a BOSS in the 90F temps today  ;D

My pressures were 30 lo 200 hi at 2000 RPM with all the doors open and a big fan blowing on the radiator.

I didn't notice any compressor cycling with the blower working and my vent temps were around 38 to 40F. I figure if nothing else screws up I'll be ready for the Ga. heat this year. And it's coming...

I'm also planning on tinting the windows before the big heat sets in... An S class really deserves decent AC, plus a 6.9L engine but that'll have to wait a little longer  ;D

I do need to check the SH though.
Title: Re: Parallel flow condenser
Post by: ZCarFan on 23 June 2012, 11:25 PM
Jon,

If I end up keeping one of the 300SDs, I'd really like to check out the installation in your car.  I've switched to driving my Caprice for the a/c but feeding the LT-1 is getting expensive with 60 miles a day on premium. 

38-40 degrees sounds great.
Title: Re: Parallel flow condenser
Post by: 1980sdga on 24 June 2012, 06:56 PM
Fix your AC and you'll keep one ;D  You got it backwards!

I've documented pretty much everything in this thread but I'll be around Newnan Ga. pretty regular for the next couple of months.