Micro-Tube Parallel Flow Condenser

[flintknapper]

. When I install my rear evap, I will be using hose instead of aluminum tubing. Reason's for this is, easier to route, wont pick up as much heat in the low line from outside (condenser has to work harder).
Scott

There are newer 'reduced diameter' barrier hoses available these days. Easy to install fittings..., less permeation rates etc...

Might be a good application for these products.

 

[Dindu Nuffin]

Due to a leaky fitting on the high side, I couldn't connect both. Why do you connect both, if the system is a loop; wouldn't one or the other be sufficient? I'm at 4780' MSL and it's about 90°F today, so I guess 25" is about right.

I ran the pump for a little over a half hour, then closed the gauge and then shut off the pump. One hour later, the needle had not budged at all.

The shop said they'd draw vacuum before filling for several reasons- to remove any residual moisture, to ensure the purity of the charge, and to check for leaks.

So, the appointment to charge it is at 5 pm today; I'll let you guys know how it goes and how this condenser and new evaporator compare to the old stuff.

 

[flintknapper]

I am trying to decide on which hose system to use. My choices are:

A. Traditional crimp hoses
B. Ez clip system by vintage air
C. Burgaflex system by proair

Looks like ez clip and burgaflex are very similar if not the same and are easier to work with than the traditional crimp method. My only worry is sourcing parts. Id like to go proair just because its local to me and the cheapest but seems like i cant find their burgaflex hoses and fittings elsewhere. Anyone here has experience with these new hoses?

Yes, B & C are nearly identical systems and the hoses and fittings are made up the same way. Both use the newer 'reduced diameter' barrier hoses. These would be a good choice for your application. Finding a source for the products (in small quantity sold to the public) might be your challenge. But if you can find the products...then for a modest investment in the necessary crimping tool and a common tubing cutter, you would be in business.

Of course, run the hose in as protected an area as possible and use insulated 'clips' to hold them in place.

 

[flintknapper]

. Why do you connect both, if the system is a loop; wouldn't one or the other be sufficient?

System is a 'loop', the reason for pulling a vacuum from both sides is not that. Using both hoses is quicker, using both hoses lets you shut off each side to check your shrader valve operation (and hose connections) and finally....IF you are charging the system yourself (in your case you are not) then you are already hooked up to liquid charge (into vacuum, engine off) through the high side with the first 12-16 oz. of refrigerant (a practice I highly recommend).

I'm at 4780' MSL and it's about 90°F today, so I guess 25" is about right.

Yep.

I ran the pump for a little over a half hour, then closed the gauge and then shut off the pump. One hour later, the needle had not budged at all.

Yep, good to go.

The shop said they'd draw vacuum before filling for several reasons- to remove any residual moisture, to ensure the purity of the charge, and to check for leaks.

Smart folks.

.

^^^^^^ expand for replies


Look forward to your report.

 

[smritte]

There are newer 'reduced diameter' barrier hoses available these days. Easy to install fittings..., less permeation rates etc...

Might be a good application for these products.

I haven't kept up with any new innovations on hose material. That's good to know.

Its also nice to see some of the aftermarket industry is also stepping up their game. It's been almost two decades since I've done any real custom work. In the past most people were happy just to have AC in their street rod, custom van..... They accepted poor engineering for one size fits all and ease of installment. It wasn't unusual to see 55 degree vent temp from custom front and especially custom rear.

Scott

 

[Dindu Nuffin]

Well boys, the tech said he got 42°F out of it and said that the AC expert they have come in on Wednesdays could probably get it down a little lower if I wanted to come back.

My knuckles were freezing on the way home and for the first time, I had to take the fan off high and redirect the ball blower. I'm really looking forward to being able to hit the trail without suffering the heat and the dust.

The real test will be taking it to work on Monday and letting it sit out in the heat all day followed by the first ten minutes of my commute being sub- 10 mph speeds. I'm stoked. :-D

 

[flintknapper]

@flintknapper Would i have a problem if i use rubber hoses to line my rear system or hard lines are necessary?

Sorry, did not see this question earlier. No....hard lines are not necessary and would be MUCH harder to run (full length).

There are newer hoses these days (reduced diameter) barrier hose (in different sizes) that accept special fittings made just for them. Basically... you cut the hose to length, lube the fitting, insert fitting and use whatever crimping rings (slightly different one manufacturer to another) to crimp the fitting in place. Not too unlike crimping a PEX fitting to PEX line (plumbing). A simple hand held (usually ratcheting) crimper is used.

Some hoses are more flexible than others...so IF you have any sharp bends you need to make...just keep that in mind.

 

[Dissent]

Delete: Not L/C related

 

[Dissent]

Well boys, the tech said he got 42°F out of it and said that the AC expert they have come in on Wednesdays could probably get it down a little lower if I wanted to come back.

My knuckles were freezing on the way home and for the first time, I had to take the fan off high and redirect the ball blower. I'm really looking forward to being able to hit the trail without suffering the heat and the dust.

The real test will be taking it to work on Monday and letting it sit out in the heat all day followed by the first ten minutes of my commute being sub- 10 mph speeds. I'm stoked. :-D

That is so awesome!! So a noticeable difference over the stock serpentine then? Remind me, do you have an aux. fan running too?

 

[smritte]

Hey guys, I tried my hand at home AC charging today and it just didn't work out at all. We did this on my son's 2004 Dodge Dakota after replacing the accumulator. The truck used to be enviably cold but when the shop did the valve cover gasket, they had to open the system. They evacuated it and recharged it using the old accumulator because they didn't have a new one. So, today we put a new one in. We sucked it down to 29 hg and it held fine for an hour. We turned the 30lb R134 tank over and fed it liquid, drawn into the vacuum on the high side for about 1.5lbs (needed 29oz total). Turned the tank over, closed the high side and started the truck to finish with a gas charge. Set the idle to 1500 RPM. The low pressure ended up at 50-55, based on our 107 ambient air, but the high side was 125 and never budged. We fought this stupid fight for about 4 hours on and off, started over from scratch will full vacuum and tried it again. The accumulator felt "beer cold" to touch but both theIR and digital stick thermometer, which I ty-rapped to the line, read 105. That didn't make any sense. It was clearly cold. The vent temp was a balmy 77. We shut it all down in frustration and went for a drive on the freeway, the vents got down to 63.

9 hours fighting this beast in the 105+ degree weather was not encouraging. He will probably have his boss look at it Monday. He's a 40 year home HVAC guy.

Uhh you sure about those pressures and your sure the AC didn't cycle off when you saw those? How did you know how much you put in?

A couple of things could have happened. When you screwed down the fittings onto the AC line, there is a small pin that push's the schrader valve open. Some times it will pop over to the side. What you will see is a high side that doesn't change. Next is, holding the rpm the compressor can cycle off. Some times you don't notice it. What you see is, the low side come up and the high side drop. Both of these my students do all the time.
Last is possible but not probable. The orifice tube is missing. If you just replaced the Accumulator you wouldn't have touched it. If you had to take apart the liquid line for whatever and pulled it out, then there you go. Ive have a few of those from body shops, same symptom.

Good luck with it, I'm sure its something simple.

@Dindu Nuffin ..Good Deal.

Scott

 

[Dissent]

Delete: Not L/C related

 

[smritte]

The compressor was engaged pretty much the whole time.

Ill try the gauges again to ensure that pin moves the Schrader valve correctly.

We used a digital bathroom scale to put in 1.5lb (24oz) but the scale would time out. Rewriting the tank confirmed the weight but I don't trust it. I want a proper refrigerant scale but tried this first. Can you recommend a decent budget scale to track the freon exactly?

We never opened the high side. It was very cold before the valve cover service last year.

Cant recommend a scale, I have machines at work. I have a scale I use to show what they are but that's about it. I can tell you that those pressures couldn't be right. My bet is on the gauge not reading. If the gauges were moving up and down and you got those there's only 2 possibilities (assuming the charge is close) and that's missing Orifice or bad reed valves in the compressor. Both of those separate pressure. One bad and the the pressures skew like that.
Still betting on simple, gauge most likely.

Scott

 

[flintknapper]

Delete: Not L/C related.

 

[Dissent]

I'm sure its something simple. Overtight fittings could be possible. Ill look for a scale.

I just read about filling the liquid side until it can't hold anymore (engine off) then closing the liquid line and charging the gas side with the engine running. Is this common practice? Does it use the vacuum to pull the liquid then equalize at some point???

 

[Dindu Nuffin]

That is so awesome!! So a noticeable difference over the stock serpentine then? Remind me, do you have an aux. fan running too?

HUGE difference! I dropped 20- something degrees off the old setup. That's massive.

Yep, i have a Perma Cool 19120 fan pushing through the condenser. When he first told me it was done, it was blowing 46°F. I asked if the fans were running constant or not, and he said no, so I went out and pushed the "always on" button for the pusher and two pullers behind the radiator. After that is when it hit 42°F. It's freakin' cold, and I don't doubt this condenser could handle the thermal load of a 2nd evaporator. I think you'll really like it.

 

[ARB777]

Sorry, did not see this question earlier. No....hard lines are not necessary and would be MUCH harder to run (full length).

There are newer hoses these days (reduced diameter) barrier hose (in different sizes) that accept special fittings made just for them. Basically... you cut the hose to length, lube the fitting, insert fitting and use whatever crimping rings (slightly different one manufacturer to another) to crimp the fitting in place. Not too unlike crimping a PEX fitting to PEX line (plumbing). A simple hand held (usually ratcheting) crimper is used.

Some hoses are more flexible than others...so IF you have any sharp bends you need to make...just keep that in mind.

The main guy i was talking to at proair was selling me their burgaflex crimper for around $90. His co worker butted in probably not knowing the guy was selling me stuff so he said i could get a pex crimper for about $20 at home depot and it should work the same. By looking at the process of crimping the ez clip/burgaflex fittings, it seems like there are no different sizes of crimpers. The crimper would do all sizes unlike the older mastercool crimper for the standard barrier hose. Am I correct?

 

[ARB777]

HUGE difference! I dropped 20- something degrees off the old setup. That's massive.

Yep, i have a Perma Cool 19120 fan pushing through the condenser. When he first told me it was done, it was blowing 46°F. I asked if the fans were running constant or not, and he said no, so I went out and pushed the "always on" button for the pusher and two pullers behind the radiator. After that is when it hit 42°F. It's freakin' cold, and I don't doubt this condenser could handle the thermal load of a 2nd evaporator. I think you'll really like it.

It would be a lot less headache if the nissens would work for the rear unit. Im glad everythings working out well for you. Do you know how much refrigerant they used to charge your system?

 

[smritte]

I just read about filling the liquid side until it can't hold anymore (engine off) then closing the liquid line and charging the gas side with the engine running. Is this common practice? Does it use the vacuum to pull the liquid then equalize at some point???

yes and no. Remember it's a loop separated by the compressor valve's. It will slowly bleed through the metering device and equalize.

When i would charge, i would open both valve's (engine off) and dump in, sometimes it would all go in and sometimes not. On the Orifice tube vehicles i would start the car and finish the charge on the low side (high valve closed).
If your charging and you watch your temp gauge in the vehicle, when it stops dropping your about full. I ran a digital temp probe that i could watch through the windshield. .25 lb difference can make a few degrees that's why you should be at least close to your proper charge. Using a machine i could get pretty exact.

 

[Dissent]

I got the VDO motor from Autozone, part number PM2503. Yep on the mineral oil and hell yep on the foam, but I'm only going to foam between the radiator and support. I'll see how the AC works and if I feel it needs any airflow management, I'll bend up some sheet aluminum ducting to seal up the sides and top between the condenser and radiator.

*edit- oh crap, I just realized that motor shows as being for a truck without AC. However, it looks identical other than color to what came out of there. We'll see in an hour or two. Stand by on that motor until I see if it fits. Sorry about that.

What blower motor did you end up with? Did it come with the fan installed or did you have to swap it? If so, how hard was it?

 

[Dissent]

Following closely. Waiting for full parts lists once everything is confirmed and working.

Based on @Dindu Nuffin's results, looks like we have a winner with the Nissens for the bolt in crowd.

@ARB777 is making something wonderful.