Is my condenser partially restricted? Photos included

[charlie_ac]

Hi guys, I was wondering if my condenser if partially restricted.

I only have a low side gauge, and I read about 60 psi on the low side which is quite high.

Temp out the vents are usually about 20-24 degrees Celsius while driving which seems very poor, especially at idle it goes to about 27 degrees.

Sometimes I pour water on the condenser and I get 18-22 degrees, but I noticed this one time that the condenser dries very unevenly, leading me to think that the condenser is partially restricted in that a large portion of tubes may be blocked, but still allow flow.

The input to the condenser, that is the compressor output line, is extremely hot, too hot to touch for up to 1 second.

I have attached pics of the water drying on the condenser, at start, after 5 mins, 10 mins and finally 15 mins of running.

Could this prove that my condenser is inefficient and should be changed?

START:-




After 5 mins




After 10 mins


After 15 mins

[Cornbinder89]

Hard to say. Without a high side reading, it is not easy to see what is going on. Too hot to hold is 130 degs or so. Each of us has a different threshold of pain.
Could be overcharged, or could be other problems. High low side is not indicative of clogged condenser, low, low side with poor cooling is more and indication of a clog. A condenser can be bad in other ways however. If it is not ridding the heat from the refrigerant (due to poor fin to tube bonding). I wouldn't jump to throwing parts at the problem. Spend you money either outfitting your self with the correct tools or paying someone to fix it.
My guess is overcharge but that is a guess.
You haven't told us what type of system or what vehicle even so it is hard to help.

[Tom Greenleaf]

What is this thing? Also how is the primary fan for it pulling air? Electric or by clutch?
Either way it's not blowing cool enough just better when moving most like that is more airflow.

Still crude basics are knowing system is properly charged by weight into a well held vacuum.

Then if proper even if not too long can nail it down better,

[charlie_ac]

Hard to say. Without a high side reading, it is not easy to see what is going on. Too hot to hold is 130 degs or so. Each of us has a different threshold of pain.
Could be overcharged, or could be other problems. High low side is not indicative of clogged condenser, low, low side with poor cooling is more and indication of a clog. A condenser can be bad in other ways however. If it is not ridding the heat from the refrigerant (due to poor fin to tube bonding). I wouldn't jump to throwing parts at the problem. Spend you money either outfitting your self with the correct tools or paying someone to fix it.
My guess is overcharge but that is a guess.
You haven't told us what type of system or what vehicle even so it is hard to help.

Thank you for your response.

Yeah I have seen some youtube videos where just as you said, a condenser restriction would lead to a low LOW SIDE, because the flow of refrigerant has been hindered, however that seems to be if there is no flow at all or min flow, but I'm thinking mine still has acceptable flow, but is just not using all the tubes like it was designed for and thus not able to transfer enough heat, while still being able to flow refrigerant.

I had a weak compressor before that was repaired LAST MONTH. Some valve plates in it were burnt so they replaced it and it was cooling well but everyday the cooling seemed to get worse and worse and the top of the condenser is not hot, though the leftmost side is hot

Does the drying time of the water on the condenser tell you anything at all?

Shouldn't all the water dry on a hot condenser quickly?

When I pour water on the condenser, the low side goes down to about 45psi.

I thought a condenser is supposed to be hot, so that if you pour water on it, it should be dry in like 10mins or maybe I'm wrong.

It's an Avensis, but it has been moded to use the "Manual" compressor instead of the "Automatic"(variable displacement) one it comes with so nothing oem applies here anymore.

[charlie_ac]

What is this thing? Also how is the primary fan for it pulling air? Electric or by clutch?
Either way it's not blowing cool enough just better when moving most like that is more airflow.

Still crude basics are knowing system is properly charged by weight into a well held vacuum.

Then if proper even if not too long can nail it down better,

That is my condenser, that I poured water on to decrease vent temps. I am concerned that it has wet spots after 10 mins which to me indicates that some tubes might be blocked so there is little heat flowing in those areas to dry the water I poured on it.


It's an electric fan, with a moded motor and shroud. My shade tree mechanic put a shroud and motor not specifically for an Avensis, but it seems to spin fast and the car doesn't overheat.

I have a vacuum pump but no manifold set, just a low side gauge. So I always vacuum before adding gas.

The car takes 470g and each can is about 250net, so even if I put 2 cans in, that would just be 500g

If I rev the car to 2000 rpm, the vent temp drops to about 17-18 degrees after about 3 mins.

I wonder if the compressor has spoilt again, or if I should just chage only the condenser.

[charlie_ac]

The last time the compressor was removed (repaired last month), it wasn't sucking when you roll it by hand and place your thumb on the port. After the repair, it started sucking well.

To check that again, I would need to remove all the gas again and see, expensive in Nigeria, but I would need to remove the gas anyways if changing the condenser. So maybe I will check to make sure the compressor is still sucking and has not burned the valves again.

Also I had a seized compressor last year, but I did not change the condenser as I couldn't afford it, so we flushed it with cooking gas, and I used my vacuum on the system for 2 hours.

I just thought I had stumbled on the problem being the condenser and how it was taking so long to dry even when the input pipe is blazing hot.

My vent thermometer is inaccurate in capturing the inlet temp to the condenser. it has a plastic probe, and it's not capable of reading that high, but it's high men, blazing hot, then 2 inches from the inlet on the condenser is like luke warm.

[Cornbinder89]

Ok, that model is not sold here as far as I know, but I think a Camry would be close kin to what you have.
Air-conditioning is a closed, free floating system. By that I mean that any change to one part of the system, effects the whole system. Being that, you can't change the displacement of the compressor and not effect everything else. Like changing weights on one side a balance scale, the system is no longer in balance.
On home A/C, for years the compressor turned a fixed RPM and everything was designed on that refrigerant flow rate. That didn't work for engine driven compressors, so some system to account for varying flow must be in place. It can be a storage tank (receiver), or accumulator on the low pressure side combined with a cycling of the clutch, but some way of controlling the movement is required.
In recent times to cut the amount of energy required, varying the displacement of the compressor has become a thing, both in fixed and mobile A/C. Fixed it is often done by using a variable frequency drive on the power feed to the compressor to slow or speed it up depending on heat load.
In mobile A/C variable displacement compressors are the way it is most often done. In doing this they do away with or greatly reduce the high side storage receiver. You can't just take a variable compressor and replace with a fixed and expect it to work.
You are essentially changing the whole design of the system by changing one thing. You have to take into account the effect of that change.
If you also made a change to the fan/airflow design from the OEM, that also can effect the system. You may need more surface area in the condenser, additional liquid storage, or even cycle the compressor to prevent overloading the high side while starving the low side.
Unless you want to take on all the R&D of designing your own system (Something I have done, and let me tell you there is a LOT of trial and error), you'd be best served by restoring to factory spec's. That may take a bunch of new parts, if your old system passed a bunch of junk through the system, and money, but you'll spend more on R&D finding out what works and what doesn't, going your own path.

[charlie_ac]

Ok, that model is not sold here as far as I know, but I think a Camry would be close kin to what you have.
Air-conditioning is a closed, free floating system. By that I mean that any change to one part of the system, effects the whole system. Being that, you can't change the displacement of the compressor and not effect everything else. Like changing weights on one side a balance scale, the system is no longer in balance.
On home A/C, for years the compressor turned a fixed RPM and everything was designed on that refrigerant flow rate. That didn't work for engine driven compressors, so some system to account for varying flow must be in place. It can be a storage tank (receiver), or accumulator on the low pressure side combined with a cycling of the clutch, but some way of controlling the movement is required.
In recent times to cut the amount of energy required, varying the displacement of the compressor has become a thing, both in fixed and mobile A/C. Fixed it is often done by using a variable frequency drive on the power feed to the compressor to slow or speed it up depending on heat load.
In mobile A/C variable displacement compressors are the way it is most often done. In doing this they do away with or greatly reduce the high side storage receiver. You can't just take a variable compressor and replace with a fixed and expect it to work.
You are essentially changing the whole design of the system by changing one thing. You have to take into account the effect of that change.
If you also made a change to the fan/airflow design from the OEM, that also can effect the system. You may need more surface area in the condenser, additional liquid storage, or even cycle the compressor to prevent overloading the high side while starving the low side.
Unless you want to take on all the R&D of designing your own system (Something I have done, and let me tell you there is a LOT of trial and error), you'd be best served by restoring to factory spec's. That may take a bunch of new parts, if your old system passed a bunch of junk through the system, and money, but you'll spend more on R&D finding out what works and what doesn't, going your own path.

Wow, this is a lot to process. No, no, no, I so do not want to do my own R&D for this car.

I thought maybe the Expansion valve was meant to "meter" the flow?

I have some friends that have switched to the fixed displacement type and had some success.

Yes my system doesn't cycle anymore, as I have bypassed the electrical connections as the oem compressor connection is pulsed for the variable compressor and has 2 wires, so I found 12v elsewhere and simply turn it off and on.

I thought compressors only cycle to control temperature though and not flow and since my vent temps never drop below 17 degrees, I figured it was okay not cycling.

Anyways, I think I will follow your advise and get a used variable compressor meant for my car and a new condenser, that way I can connect the wires that control the compressor from the car that are now left unused.

------------------------------------------------------------

This is the oem shroud below, mine is like that, but all the vertical holes highlighted in Yellow are all blocked with plastic, like a solid construction. So the only hole on mine is the round hole where the fan blades go.

I though mine would be more efficient as I have read fan shrouds should have only one hole to be more efficient; the fan hole.

I guess the oem must have reasons for placing those four sets of vertical holes, I just can't understand why.

Thank you so much again!

[Cornbinder89]

We were both type responses at the same time, so I didn't get your last until after I finished mine.
If I were going to attempt this on the cheap. I would put high pressure taps both before and after the condenser. The pressures should be close (but not exactly the same, there has to be a pressure drop for heat transfer to have happened) You may have a restriction somewhere, but without knowing how high the pressure is before and after the condenser you can't tell how well the heat transfer is.

A piercing valve like the above can be used to add a tap to a charged system. While they do work, I don't know that I would leave on the system all the time, I think in a car it may lead to pipe breakage over time, but does allow you to try things and find bad spots.
Because they are for commercial refrigeration, they are 1/4" flare and an adapter would be needed for R134a.
A/C compressors are cooled by the returning cool vapor, if it isn't cool or isn't enough the compressor can cook, the oil can coke and stick in the reed valves and prevent it from compressing.
Without high side readings it is impossible to tell what is happening in your system. By adding more High side taps, you can see how the pressure compares over different parts of the high side of the system. It will show restrictions by vastly different pressures.
A/C isn't cheap, and I understand where you are at, you may not have what is available to us here.
Another thing you can do if you can lay your hands on an old electric compressor out of a domestic fridge, is drain the oil, and re fill with oil that they type in your car compressor, and get an old pressure tank, may be from cooking gas and evacuate it with a vacuum pump, then use the refrigerator to pump the gas from you car to the tank, and back again after repairs are made.
I should caution that you WILL contaminate the system with a little residual propane that will be in the gas canister. This is not "legal" to do here and I imagine where you are also, but "needs must when the devil drives" as they say.

[Cornbinder89]

The extra holes are so when the car is at speed it can allow the "ram air" to pass through the condenser and fan. Without them the fan would go from a help drawing air through to a hindrance getting air through once the car is at speed. I've seen some that have hinged flaps when the use an electric fan, so when the fan is causing a low pressure area behind the heat ex-changer, the flaps seal, and when ram air raises the pressure they open and let more air flow through.

[Cornbinder89]

Something like the above can be brazed onto the refrigerator compressors tubes and give you a place to hook you manifold gauges and hose to the LP tank.
Sort of a "poor mans" recovery machine.

[charlie_ac]

We were both type responses at the same time, so I didn't get your last until after I finished mine.
If I were going to attempt this on the cheap. I would put high pressure taps both before and after the condenser. The pressures should be close (but not exactly the same, there has to be a pressure drop for heat transfer to have happened) You may have a restriction somewhere, but without knowing how high the pressure is before and after the condenser you can't tell how well the heat transfer is.

A piercing valve like the above can be used to add a tap to a charged system. While they do work, I don't know that I would leave on the system all the time, I think in a car it may lead to pipe breakage over time, but does allow you to try things and find bad spots.
Because they are for commercial refrigeration, they are 1/4" flare and an adapter would be needed for R134a.
A/C compressors are cooled by the returning cool vapor, if it isn't cool or isn't enough the compressor can cook, the oil can coke and stick in the reed valves and prevent it from compressing.
Without high side readings it is impossible to tell what is happening in your system. By adding more High side taps, you can see how the pressure compares over different parts of the high side of the system. It will show restrictions by vastly different pressures.
A/C isn't cheap, and I understand where you are at, you may not have what is available to us here.
Another thing you can do if you can lay your hands on an old electric compressor out of a domestic fridge, is drain the oil, and re fill with oil that they type in your car compressor, and get an old pressure tank, may be from cooking gas and evacuate it with a vacuum pump, then use the refrigerator to pump the gas from you car to the tank, and back again after repairs are made.
I should caution that you WILL contaminate the system with a little residual propane that will be in the gas canister. This is not "legal" to do here and I imagine where you are also, but "needs must when the devil drives" as they say.

Not sure that can be found here in Nigeria, but I do have the high-pressure tap (after the condenser), so I can go take readings at a shop that has both high and low gauges. I will also ask my ac mechanic if he has an input line (before condenser) with a tap built in to experiment. I don't mind paying for gas twice as long as I can get good results to be honest, as I'm not too good at rigging stuff up like you said, might end up blowing myself up!

The high side is not hot though, that I know for sure, only the inlet to the condenser is blazing hot, and the outlet line is just warm, barely. Even early in the morning when it works best, cold engine, high warm up rpm, the low side would be cold and the high side, barely.

So, I guess you're saying, the higher the low side, the faster you cook the compressor, interesting! I guess I'm only biding time now as mine is 60psi, so not so cool. Unless I start pouring water on the compressor after every 20 mins drive (poor man cooling)

At this point, I'm just gonna roll with this system till the "wheels fall off", so to speak and then hopefully I can find a good used OEM compressor, but here in Nigeria, they all lie that the compressor is good, but they probably already opened it to do some work, can't trust anyone here. Or I could start planning now to ship a used one from abroad.

I will invest money in getting my own manifold gauge set so I can do some more troubleshooting in the future without going anywhere.

Thank you Combinder89, you guys are really knowledgeable here.

[charlie_ac]

Something like the above can be brazed onto the refrigerator compressors tubes and give you a place to hook you manifold gauges and hose to the LP tank.
Sort of a "poor mans" recovery machine.

lol, how do you guys even come up with all of this? damn!

I need to change countries men

[Cornbinder89]

the two fittings (piercing tap and braze on tube) are for commercial refrigeration, not automotive and many who work on cars will not have seen them. Someone who works on building refrigeration will have.
If the inlet to the condenser is HOT but cool outlet (esp if it is cooler than the air passing through it), feel along the tubes of the condenser. If you find a place that goes from Hot to cold, you have found a restriction, if it goes from hot at the inlet to gradually cooler but still above the temp of the air passing through the condenser, then there is no restriction and the condenser is shedding heat.

[Cornbinder89]

Oh, and to answer you question many post back about the function of the Tx valve at the evaporator. It has two jobs, 1st it is a restriction between the high and low pressure sides of the system. 2nd it is there to regulate the amount of liquid refrigerant into the evaporator such that it all boils to gas by the outlet. Too much refrigerant and it will not all boil by the outlet, too little, and it will all turn to gas before it leaves the evaporator. (same thing as installing too small an evaporator). It does this by looking at the temp (pressure) just after the restriction, and comparing to the temp (or pressure) of the outlet of the evaporator.
So you were correct in a sense. but when the supplied flow from the compressor exceeds the flow through the valve the pressure rises, making the two sides (high and low). High side pressure is determined by the temp that hot gas condenses in the condenser. Once it turns to liquid, the amount of heat removed drops.
When the compressor output exceeds demand by a large amount, the excess liquid gets stored as a high pressure liquid in the receiver. If the receiver isn't big enough, liquid refrigerant backs up in the condenser, reducing the area available for the hot gas to shed its heat, so pressure rises further.
In ideal conditions, the refrigerant would looses all its heat above the temp of the air passing through the condenser, and the high side pressure would be that of the temp of the air passing through (look to pressure/temp charts on reference section of this site) Heat is given up or absorbed but the phase change from liquid to gas or gas to liquid. Without that phase change you might as well try and cool using compressed air.

[Tom Greenleaf]

Compressed air Cornbinder! Oh me. oh my. Quite the read here this isn't helping (me) the compressed air TMK is in use to make snow for recreational sport, downhill skiing when not enough has come or a busy place wears off areas.

Scuba tanks, other filled tanks if released quickly will blow fog and cold even ice up trouble is that's 1,000s of PSI never turns to liquid.

Carry on you 2 see what can be done with this I'll do more watching.

Home A/C is on now if just to dump out the oppressive humidity to me. Pretty much if not that A/C really wouldn't be needed much where I am just hide during the 10 days all year it pulls that,

[charlie_ac]

Oh, and to answer you question many post back about the function of the Tx valve at the evaporator. It has two jobs, 1st it is a restriction between the high and low pressure sides of the system. 2nd it is there to regulate the amount of liquid refrigerant into the evaporator such that it all boils to gas by the outlet. Too much refrigerant and it will not all boil by the outlet, too little, and it will all turn to gas before it leaves the evaporator. (same thing as installing too small an evaporator). It does this by looking at the temp (pressure) just after the restriction, and comparing to the temp (or pressure) of the outlet of the evaporator.
So you were correct in a sense. but when the supplied flow from the compressor exceeds the flow through the valve the pressure rises, making the two sides (high and low). High side pressure is determined by the temp that hot gas condenses in the condenser. Once it turns to liquid, the amount of heat removed drops.
When the compressor output exceeds demand by a large amount, the excess liquid gets stored as a high pressure liquid in the receiver. If the receiver isn't big enough, liquid refrigerant backs up in the condenser, reducing the area available for the hot gas to shed its heat, so pressure rises further.
In ideal conditions, the refrigerant would looses all its heat above the temp of the air passing through the condenser, and the high side pressure would be that of the temp of the air passing through (look to pressure/temp charts on reference section of this site) Heat is given up or absorbed but the phase change from liquid to gas or gas to liquid. Without that phase change you might as well try and cool using compressed air.

Bro, thanks once again for your intelligent responses to my issue, may God bless you loads!

I have fixed the problem and wanted to report back since it has been 2 weeks of hustling for money and repairs.

The problem turned out to be the compressor that was repaired.

I know you told me to wait to do it right, but since I use the car for Uber in Nigeria, I can't afford to go one day without AC, passengers would complain, so I decided to buy another fixed disp compressor, but the AC guy said it belongs to a Peugeot.

Broooooooo, the AC is now FREEZER cold, like, I havent had AC like this since the car was new. Turns out it's a SANDEN compressor and I must say I am impressed.

I think where I went wrong was spending half the money for this used sanden compressor to repair the other one. The old compressor did work after the repair, but each day, it seemed to die more and more, and I really don't know why. Maybe the repair wasn't done well.

I also bought a new aftermarket condenser since they are relatively cheap here in Nigeria, costing about N25,000 (~$30)

I am so happy, and my passengers now even almost fall asleep when the AC is on, lol

Checking the low-pressure gauge (still don't have a manifold), I am seeing readings of about 35psi, which is fantastic. I used to see about 60-70 psi before.

The low pipe is ICE COLD.

I really had been getting scammed by compressor sellers in the past it seems (lots of scammers in Nigeria men), and going forward, if I ever need a replacement compressor, it must be able to pull down to 40psi on the low else I will return it the same day. Of course, the prayer is to be able to afford brand new parts, cause if a used compressor is freezing me over, then I can only imagine what a BRAND-NEW OEM COMPRESSOR will do.

Thanks again and God bless and prosper you bro. I hope to be an active member of this forum in the future.

[Cornbinder89]

Glad you got something to work for you.