Ac condenser replacement

[Mooseman]

Try this. Take the filter out and with the A/C running with fan on low, put your fingers on the evaporator to feel how cold it is. If it's cold, I have a feeling it's the hot/cold blend actuator(s) that's probably broken. Does the vent temp go up and down when you turn up/down the temperature? You could remove the actuator and turn the door by hand to see if that works.

This post has a diagram of the actuators:
http://gmtnation.com/forums/topic/9109-front-mode-actuator-problem/?p=193278

 

[Trkdrvremt]

The vent temp changes.. 60 on ac 140 with heat both taken on high...

Should I still see what temps I get on low?

 

[littleblazer]

Try this. Take the filter out and with the A/C running with fan on low, put your fingers on the evaporator to feel how cold it is. If it's cold, I have a feeling it's the hot/cold blend actuator(s) that's probably broken. Does the vent temp go up and down when you turn up/down the temperature? You could remove the actuator and turn the door by hand to see if that works.

This post has a diagram of the actuators:
http://gmtnation.com/forums/topic/9109-front-mode-actuator-problem/?p=193278

My problem with that is it would be coincidental that both sides went at the same time. Anything is possible I know.

The vent temp changes.. 60 on ac 140 with heat both taken on high...

Should I still see what temps I get on low?

When mine was undercharged, the coldest was 3 and driving for a while. I actually have a thermometer in the vent at all times. [emoji13] highway should level around 45, around town a little lower. If it gets colder on a lower fan speed it'll need more freon. It's not bad to get out the passenger side actuator either though to check. Right on the left side of the glove box by the radio if I remember right. Set it to max cold then take it off and see if it moves anymore.

 

[littleblazer]

78 ambient temp fan speed 3

 

[Tiggerr]

Didn't you say your new condenser was aftermarket, and had less tubes then OEM? Wonder if the condenser you got is not enough. Could be your evaporator's blocked up too, On the inside. You said you have good airflow I believe. Did you flush the system before you charged?

 

[Ziggy]

I'm a little late to the party here. I've read through the thread - although my reading was broken up with interruptions, that pesky work thing, you know - but I didn't see; Did you replace the receiver/drier?

Number 9 in the illustration below:

If you've not replaced the Receiver/Drier assembly yet, You should probably go ahead and do that. You mentioned that you don't know how long the leak has been there... Those receiver/driers can only handle an open system for about a week or two of being open after they've been put into use. My estimate software has the receiver/drier assembly available from GM for $81.68 - pn: 15883410, probably available aftermarket for $20-$30 less. Pays a half hour labor to replace, so probably the worst part of the process will be pulling a vacuum on the system so you don't lose all that refrigerant you just introduced to the system.

 

[Trkdrvremt]

Didn't you say your new condenser was aftermarket, and had less tubes then OEM? Wonder if the condenser you got is not enough. Could be your evaporator's blocked up too, On the inside. You said you have good airflow I believe. Did you flush the system before you charged?

Yes on the aftermarket.... No on the flush...

 

[Trkdrvremt]

I'm a little late to the party here. I've read through the thread - although my reading was broken up with interruptions, that pesky work thing, you know - but I didn't see; Did you replace the receiver/drier?

Number 9 in the illustration below:

If you've not replaced the Receiver/Drier assembly yet, You should probably go ahead and do that. You mentioned that you don't know how long the leak has been there... Those receiver/driers can only handle an open system for about a week or two of being open after they've been put into use. My estimate software has the receiver/drier assembly available from GM for $81.68 - pn: 15883410, probably available aftermarket for $20-$30 less. Pays a half hour labor to replace, so probably the worst part of the process will be pulling a vacuum on the system so you don't lose all that refrigerant you just introduced to the system.

Yes and the orifice tube was replaced

 

[Tiggerr]

IIRC your supposed to flush the system after major work like condenser, drier etc..might just be for compressor replacement. Not sure. Maybe the condenser isn't adequate for the system...idk. Seems like you did everything else to spec. Can't see why your still not cooling other than those two things.

 

[Trkdrvremt]

Ok IIRC I counted 47 tubes on the one I removed and 43 on the new aftermarket one. Would 4 less make that much of a difference? My next option I guess will be to take it and get it evacuated, flushed and recharged and see if that helps any. But first I will try to remover the cabin filter and look at the actuator... Now to find the time .... Lol

On a side note if there was crap in the system would it not cause higher pressures on top of less than par cooling?

 

[littleblazer]

Thats significantly less surface area for heat dissipation. Generally crap will elevate the low and keep the high the same if I remember correctly. Don't pin me on that.

 

[Mooseman]

For the flush, it depends on several factors. If a compressor failed, the system was left open/disconnected for a while or you don't know how much oil is in the system. The oil is hygroscopic so if it is exposed to air for a long time, it will deteriorate by the moisture it absorbs. A flush would not make any difference but it could affect the longevity of the compressor. Personally, I have never flushed a system, even one that had a leak and wasn't used for years. It should not affect temperature performance.

Did you check to see how cold the evaporator gets through the filter opening?

 

[Trkdrvremt]

Did you check to see how cold the evaporator gets through the filter opening?

Not yet

 

[littleblazer]

Don't know how it is by you, but central Jersey is supposed to be mid to upper 90s with pretty high humidity, good for getting an accurate pressure reading. [emoji106]

 

[Trkdrvremt]

Yeah well... Working in sea isle city all day today...

 

[Trkdrvremt]

Try this. Take the filter out and with the A/C running with fan on low, put your fingers on the evaporator to feel how cold it is. If it's cold, I have a feeling it's the hot/cold blend actuator(s) that's probably broken. Does the vent temp go up and down when you turn up/down the temperature? You could remove the actuator and turn the door by hand to see if that works.

This post has a diagram of the actuators:
http://gmtnation.com/forums/topic/9109-front-mode-actuator-problem/?p=193278

Going to look at this today... Which one would be considered the hot cold temp in the pic? Pass temp and driver temp?

 

[littleblazer]

Going to look at this today... Which one would be considered the hot cold temp in the pic? Pass temp and driver temp?

Yes

 

[Mooseman]

Don't forget to check if the evaporator gets cold too.

 

[Trkdrvremt]

Both actuators are fully open...
Evap seems to be cold the further left I feel but not so much on the right. Also found some water on the panel.


The evap doesn't stay cool for long once I kill the ac it stays cool for less than 20-30 seconds.

Also pressures yesterday at 85 degrees.. 50 low side 240 high side... Still 60 at the vents.

 

[Mooseman]

Althouh not related, Your drain tube might be plugged. Go on the firewall, pull the tube out and put the shop vac on the nipple to suck out the water and muck.

Low side seems high. Have you tried misting some water from a garden hose on the condenser while it's running to see if it improves performance? I'm thinking that it's now overcharged.

 

[Trkdrvremt]

Ok now I'm confused... As per the temp chart at 85 degrees it say low side should be between 45-55.. I tried the hose trick with no change at all.

 

[littleblazer]

Ok now I'm confused... As per the temp chart at 85 degrees it say low side should be between 45-55.. I tried the hose trick with no change at all.

It seems over0charged now...

 

[Mooseman]

I'm on my phone right now. I'd have to re-read the thread so we don't chase our tails too much.

 

[Tiggerr]

I'm thinking you need to have it evac'ed and recharged. Something's off. I know you vacuumed it down but maybe something happened when you charged.. A little air, moisture, too much oil, maybe too much 134,... pressure is close enough. It should be doing better than that. I still wonder about that condenser too, being aftermarket/smaller. Still would think it'd be better than 60 at the vent though.

Make sure that evap isn't gunked up too if you can get in there to see.

 

[littleblazer]

I'd normally agree with that, but mine preferred to be around 38 on the low at 85 degrees, that resulted in 43 out the vent. But I think some guy added that leak stop stuff to my system too, it has a small leak.

 

[Mooseman]

I wouldn't trust leak stops. Plugs leaks as well as everything else.

 

[littleblazer]

I think it may have been the previous owner. Also explains the large amount of uv dye.

 

[Mooseman]

Found some useful info:
http://www.aircondition.com/tech/questions/82/Troubleshooting-with-Gauges-FAQ

So according to them, 30 PSI on the low side is just about right. For high side, they say temperature in F + 100 would be close to what you should have. So on a 85F day, it should be around 185 PSI.

Just thought of something else. If your replacement has less tubes, maybe it would lower the amount of refrigerant required and cause an overcharged condition.

 

[Tiggerr]

Just thought of something else. If your replacement has less tubes, maybe it would lower the amount of refrigerant required and cause an overcharged condition.

That's a good point. Don't think any of us thought of that one. Overcharged is as bad as under. Maybe worse.

 

[gmcman]

Just curious, how do we know how much freon is going in? Is the OP using a scale or just going by weight on the can?

 

[Tiggerr]

Think he went by ounces in can

 

[Mooseman]

That also has its issues as you lose a bit in the lines as well as the little bit that stays in the can. You also have to be sure about the conversion from ounces to pounds.

 

[Texan]

As a shade tree guy, I agree that weight method is best,
but you need the proper equipment and start from a completely
empty system. Also need a big jug of 134r.
I wonder if a IR temperature gauge reading the accumulator
under various running conditions would give a hint as to the
level of liquid Freon in it. If it runs out of liquid, it will quit cooling.
I think.

 

[Mooseman]

One training video I saw from Napa is that they use a machine that measures the temperatures of condenser lines in and out to see see if it is effective. Same thing for the evaporator. I suppose the same thing could be done with an infrared temperature gun.

https://www.youtube.com/watch?v=laYPM2XQOpQ


Lots of info here.
http://www.napabeltshose.com/training

 

[Texan]

That was a interesting video, thanks Moose. 4 Seasons has been
around for a long time and right in my neighborhood. My 03TB has
138k miles with original AC running 10 months/year (knock on wood).
I helped my nephew replace 04TB compressor last year, still working.
I wish that there was a sight glass like in the old days. You could fill it
till the gas bubbles disappeared. I just feel the accumulator for temperature
and look for sweating. Ours use a orifice tube, not a expansion valve as
shown in the video. Wish there was a simple solution.

Edit: if you go to Moose link above and scrool down to
tech tip library, temperature control, properly charging
a vehicles AC system, you will more info. It is a word file.

 

[jsheahawk]

I (awesomely) ran a self-tapping screw into my condenser while remounting my aux trans cooler. I'm replacing the condenser in the next couple weeks, and I'm curious what your opinions are on the different condensers on Rock Auto. They range from $50 to $150.

LINK for your pleasure.

 

[Paul Bell]

Most aftermarket less expensive condensers have less tubes than the OEM units. Less tubes = less cooling.

 

[jsheahawk]

Most aftermarket less expensive condensers have less tubes than the OEM units. Less tubes = less cooling.

That seems to be what I'm reading. So OEM condenser. Plus: Orifice tube, accumulator, and gasket kit from Rock Auto. Anything else I need to replace since it's been opened to the atmosphere? I'm getting PAG oil, dye, and refrigerant locally.

Side thought: This community rules.

 

[Trkdrvremt]

That seems to be what I'm reading. So OEM condenser. Plus: Orifice tube, accumulator, and gasket kit from Rock Auto. Anything else I need to replace since it's been opened to the atmosphere? I'm getting PAG oil, dye, and refrigerant locally.

Side thought: This community rules.

Yeah as you read I learned the hard way not to go aftermarket... But your list sounds correct for parts needed.. Are you charging it yourself? If so you need gauges and a vacuum pump, both are rentable...

 

[jsheahawk]

Yeah as you read I learned the hard way not to go aftermarket... But your list sounds correct for parts needed.. Are you charging it yourself? If so you need gauges and a vacuum pump, both are rentable...

Yep. Doing it myself. A buddy is giving me a spare set of gauges, and I'm buying a HF 2.5CFM vacuum pump. The best thing about repairs is that you have to buy new tools. "Baby, I have to have them!"