Automotive Air Conditioning Information Forum

hello,

so i bought a new to me 1990 toyota corolla and the ac was ice cold. a month later that ac was warm. i took it to a ac repair shop where they told me that the system had leaks in the lines and the evaporator. the ac shop changed out the evaporator for a new one, new expansion valve, new drying air filter and new o rings in some lines. the shop also supposedly fixed a couple of leaks in the lines.

it was cooling all right when i picked her up from the ac shop.

two weeks later the ac cools at night time but during the hot day it does not cool. i took it to the ac repair shop again. it was probably 90 degrees fahrentit temperature for the morning and the best ac center vent temp measurement was 55 degrees fahrenheit.

the ac shop took some coil cleaner and cleaned the conderser coils. the ac center vent temperature dropped 5 degrees to 50 degrees fahrenheit after the condenser coil cleaning.

this car was originally r 22 so only has low pressure valve. the low pressure psi was 28 psi. the ac shop that that was good low side pressure as according to ac shop low side pressure is good between 30 and 45 psi.

ac shop says that to make car cool better that the condenser fan motor might have to be replaced, an electric auxiliary fan might have to be installed , including also perhaps a new condenser.

what stumps me is why when i bought the car the ac was ice cold?

i would imagine the guy who sold the car to me probably recharged the freon right before i went to see the car, but that doesnt explain that if there are no leaks why the car doesnt cool in the day like before when i bought it.

i dont know whether to follow the ac guys recommendations or take it to another ac shop to get a diagnostic and see if there is a freon leak still somehwere possibly.

wih outside temperatures at around 90 degrees fahrenheit. the center vent ac temp is 60 degrees fahrenheit. when under 2000 rpm perhaps at 90 degrees F outside temperature the center venct ac temp best is 50 degrees fahrentheit.

only at night when outside temperature is around 80 degress F does the ac center vent temp go down to 40 degrees Fahrenheit.

what to do?

thanks

J

Find a shop that just does not toss parts at an issue!

Not there to check myself. I believe you have the normal high head pressure do to a conversion.

Simple thing you can do to see if this is true. Get vehicle running with a/c on. Run a minute or so and feel or record vent temp. Have someone lightly spray some water across the condenser. Watch and see if vent temps come down.

<<this car was originally r 22 so only has low pressure valve. the low pressure psi was 28 psi. the ac shop that that was good low side pressure as according to ac shop low side pressure is good between 30 and 45 psi.>>

I think you meant R12 not R22. As mentioned, you need a real AC shop.

Tim wrote:this car was originally r 22 so only has low pressure valve.

I don't believe I've ever seen a Toyota Corolla without a high-side port, even on an original R-12 car like yours. Typically, it's near the receiver/dryer on a high-side refrigerant line adjacent to the condenser at the front of the car. If it's down low, it might be hard to see.

Sounds to me like the system still has a leak someplace, maybe from the compressor shaft seal. Did the shop check for that? If not, they should place a shower cap over the front of the compressor. After a couple of hours, they should slip an electronic refrigerant-detector probe under the shower cap. If the detector sounds off, they've found the leak. A competent A/C shop will know how to do this.

90rolla wrote:ac shop says that to make car cool better that the condenser fan motor might have to be replaced, an electric auxiliary fan might have to be installed , including also perhaps a new condenser.

Possibly, but I'd do the water-spray test as previously outlined and then have the shop check the compressor shaft seal for leakage.

Professional shops that specialize in mobile vehicle A/C can be hard to find. Try asking around locally for recommendations.

Dougflas wrote:<<this car was originally r 22 so only has low pressure valve. the low pressure psi was 28 psi. the ac shop that that was good low side pressure as according to ac shop low side pressure is good between 30 and 45 psi.>>

I think you meant R12 not R22. As mentioned, you need a real AC shop.

sorry i didnt know diference between r12 and r22

Tim wrote:Find a shop that just does not toss parts at an issue!

Not there to check myself. I believe you have the normal high head pressure do to a conversion.

Simple thing you can do to see if this is true. Get vehicle running with a/c on. Run a minute or so and feel or record vent temp. Have someone lightly spray some water across the condenser. Watch and see if vent temps come down.

i ran the ac for a while walked outside and threw some water from a cup on the condenser and then went back to see any change in vent temp. didnt see no change.

JohnHere wrote:

Tim wrote:this car was originally r 22 so only has low pressure valve.

I don't believe I've ever seen a Toyota Corolla without a high-side port, even on an original R-12 car like yours. Typically, it's near the receiver/dryer on a high-side refrigerant line adjacent to the condenser at the front of the car. If it's down low, it might be hard to see.

Sounds to me like the system still has a leak someplace, maybe from the compressor shaft seal. Did the shop check for that? If not, they should place a shower cap over the front of the compressor. After a couple of hours, they should slip an electronic refrigerant-detector probe under the shower cap. If the detector sounds off, they've found the leak. A competent A/C shop will know how to do this.

90rolla wrote:ac shop says that to make car cool better that the condenser fan motor might have to be replaced, an electric auxiliary fan might have to be installed , including also perhaps a new condenser.

Possibly, but I'd do the water-spray test as previously outlined and then have the shop check the compressor shaft seal for leakage.

Professional shops that specialize in mobile vehicle A/C can be hard to find. Try asking around locally for recommendations.

ac guy said that there is a r12 high side port but that the gauges dont fit on it to read the pressure so ac guy
recomended to cut old r12 high side valve and retrofit a new r134 high side valve so gauges can read high side
pressure.

second ac guy said low side valve center had leak. first ac guy says even if low side valve center has leak that
there is a cap on low side valve that doesnt allow leak.
Last

sounds to me like a leak also. shop doesnt electronic leak detector probe. shop says that they dont know where there are compressor shaft seals for the compressor.

They make an adapter for the high side port to fit R12 gauges.

As well as a link for the Santech items for your model compressor.

https://www.ackits.com/santech-compress ... so-10pa15c

First AC guy says that I have a 10p15 compressor. First AC guy says that a 10 pa 17 compressor would be better. First Ac guy says compresor is at 40% and to lower the AC vent temperature from 60 degrees fahrenheit a new compressor would be necessary. The car has a 10 p15 compressor. First AC guy says that a 10 pa 17 compressor would be best. There is a used japanese toyota denso 10 pa 17 compressor and also a new chinese compressor 10 pa 17. Which one is better?

It appears that the original Denso 10P15 compressor on your car has a single-groove V-belt pulley while the 10PA17 variant has a serpentine-belt pulley, which won't fit your stock setup unless you change over completely to a serpentine configuration...or change the clutch.

a cup of water isn't much at all.
What we have in mind is a garden hose with continuous flow

tbirdtbird wrote:a cup of water isn't much at all.
What we have in mind is a garden hose with continuous flow

i am going to get a hose and wet condenser and see what happens

JohnHere wrote:It appears that the original Denso 10P15 compressor on your car has a single-groove V-belt pulley while the 10PA17 variant has a serpentine-belt pulley, which won't fit your stock setup unless you change over completely to a serpentine configuration...or change the clutch.

i went to a third ac guy who said since the corolla was converrted from right hand drive to left hand drive that they wouldnt touch the car because they have had a history of complaints from owners of converted lhd cars. third ac guy recomended to build a metal hvac box with four ducts for the ac windows in the cabin because since the car was converted from rhd the ac was also adapted and the hvac box had leaks, also said that the compressor was making a noise and that the compressor cooling score was at around 40 por cent on a scale of 0 to 100. third ac guy recommended fourth ac guy who worked with him before.

fourth ac guy took apart the dashboard removed the adapted hvac box and installed metal hvac box with 4 ducts. ac vent temps are same as before but the airflow is noticeably better as in stronger. fourth ac guy said he found a leak in the evaporator and showed me a pic of evaporator leak and repaired it.

fourth ac guy recommends to lower temperature to set a adjustable compressor cut off valve so compressor can cut off at 40 degrees fahrenheit because the current compressor cut off valve is not adjustable. fourth ac guy says that variable compressor cut off valve would cut compressor off when temp reaches 40 degrees fahrenheit but that would stress the compressor so he recommended to install insulating material between the floorboard and the cabin carpet so the cold wont be lost so easily.

fourth ac guy recommended to do this variable compressor cutoff valve installation and insulating material installation to lower ac vent temperature to 40 degrees fahrenheit.

fouth ac guy says 10 pa 17 compressor on corolla would need a bigger condenser than current one so for a new compressor with current installed condenser a 10 pa 15 compressor would do.

going back to third ac guy to show new duct system and get reccomendations.