Hello everyone new to the forum here, and I figured I would start off like every other noob here and ask a tech. question...

Im currently working on my 90 crx si with the DOHC 1.6 in it, The A/C compressor will not turn off and I have replaced quite a few parts with ones that I have tested and new ones as well. That's not my biggest issue though, I did A service on it flushed all the old oil out and did a retro fit kit to got to the r134a. I was told that this system should have ester 100 (Please tell me if this is the wrong oil) in it to function properly, so I added the recomended 4.4oz throught the system where it should be put. charge it up to 1.6LBS. to start and then add the .2 lbs to get the full capacity the the system recomends the pressure gauge rises up on the high side to like 400-450psi and the low side hits like 70psi. there is no cold air coming from the vents at that time and the low hose is hot and so is the High side. The compressor then cuts the clutch off, I have replaced the pressure switch hoping that this might be the cause of that but no luck there. I have flushed the system, replaced the reciver dryer as well and I vaccum the system for 30 minutes before I add any r134a. So I dont think the expansion valve is failing because I have replaced this aswell. Any insight to the issue would be really helpful, thank you for taking the time to read this..

 

Self bump, I need some help please guys!

 

Your pressures seem really high.

Are both your fans on when the A/C is on?

 

well you've certainly done some troubleshooting to say the least. which system recommends those pressures? the kit? those numbers are very high compared to what a normal system would run at..

check this out, it may help.

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/%5Bfaq%5D-how-charge-your-c-air-conditioner-conditioning-system-home-1665946/

 

Yes sir both fans come on as soon as the A/C button is depressed

 

Bro thank you for the direction to look, I sent him PM to hopefully get some help no info on the writeup but damn it was good!

 

your pressures are INSANELY to high, take out some refrigerant, you should be looking at 25-30psi on your low side. take out either all of it and restart or take out a little and keep rechecking pressures to get them close to that range

 

you flushed the oil out and did a retrofit? whered you buy your ac machine caus i want one! lol and i never fully understood the whole retrofit thing to 134...all you do is remove all r12 and replace with the ozone safe new stuff

 

I did that as well sadly and no luck there either, im using an refrigerant recovery and recycling mechine. I know from the AC classes that I have taken that 30/180 is about what I should look at for "par"

 

Im using a unit by RTI I believe, sadly you arnt gonna find one for less than 1k and working at a shop I get lucky enough to use one. If you look at the thread that D16Sihatch posted the gentalman that did that write up has a pump he rents for like 40.

 

ok, well at least you've taken classes rather than alot of people who just try to do something, will mess it up, then jump on here and throw out lifelines. Then try to figure out what problem it was that they caused in the first place.....wiring is the worst. Are you sure your compressor is kicking on?

 

as for the oil question in your first post, as far as I know all 134 will take ester and all R12 should be mineral oil, so I really don't think thats your problem.

 

You stated in your first post that your compressor will not turn off, if you are filling the system with the correct amount of freon something must have a blockage to create those pressures. You could have a clogged condenser. Another thing you might check is your thermostat that is mounted on the side of the evaporator box, from my understanding it also tells the compressor when to shut off and on. Honestly it sounds like you must have some kind of trash in the system.

 

check the temps of all your lines/ condensor while the system is operating and post them on here.

 

Brand new condenser, compressor, thermostat, expansion valve. blew through well when being flushed. Ive been thinking the same too but the numbers are on the low side never go into vaccum and I was told that it will always do that if there is a block in the system.

 

The compressor is on sadly, and I kinda figured that the ester is fine too, but no matter where I call I cant get what it calls for. I will get you guys temtatures for sure I just need to recharge the system. I cleared it all out and put it in a deep vaccum for the time being.

 

eh I really dont think your problem is a system block, if you uderstand how A/C systems work that definately doesnt sound like your problem. With the new machine just try a SLIGHT undercharge maybe just 1-2 oz.

 

i would not worry about the compressor staying on! it only cycles to keep the evaporator from freezing over that is what the a/c thermo sensor is for, it tells the ecm when the temp is gettin to cold then it'll shut it off . since your a/c isn't blowing cold there is no reason for it to cycle so this is normal.. from what i read sounds like theres to much freon in the system alot of times due to equipment error i don't know what kind of machine your using so here's a trick you can try: put the system into full vacuum then turn on(engine running) your car, put the a/c to full blast and make sure the vents are set to recirculation (at this point the a/c won't turn on because theres no freon thats o.k) then charge the system little by little till the compressor kicks on and (i'm assuming you have gauges hooked up)then charge more until the gauges read between 20-30 psi on low side and 150-200psi on the high depending on the weather and humidity. rule of thumb is that temperature out of the vents should be about half of outside temp....hope this helps

 

Okay so I gave this a shot and no luck still its cold only while im charging it, then it goes to room temp and warmer... Is there an oraface tube in this system?

 

Im getting these numbers at about 1.2 lbs r134a, how ever im not getting any cold air except when I add more. also the compressor stays on is there is refregerant or not but I have a cut off switch to prevent it from running when there isnt anything in it.

 

Should be a txv system I believe

 

Hmm I Need a few to become fimaliar with the term, I dont think I have herd it before.

 

There are only 2 types of restrictions in A/C systems TXVs (Thermostatic Expansion Valves) and Orifices. How to tell what type your system uses is pretty simple. If you have 2 low pressure lines going into your firewall you have a orifice. If you have one high pressure (skinny) line and one low pressure (large) line then you'll have a TXV. Or if you know the difference between a receiver/dryer or an accumulator then you'll be able to tell also if you have a accumulator (will look just like the receiver dryer but will be in between your condensor and your restriction/ Evaporator) you will have a orifice for a restriction. If you have a receiver/dryer (located between your compressor and your condensor) then you will have a TXV.

How the TXV works (just for your own personal knowledge): basically it will have a temperature gauge towards the outlet of your evaporator. Based on the outlet temp of the evaporator it will either open or close the restriction before the evaporator. Obviously the more restriction the colder the refrigerant gets because the in/hg is decreased thus the boiling point of the refrigerant is changed. Hope that explanation at least helps you understand how the TXV works and why it's most likely not your problem in my opinion.

 

pretty good explanation of the txv

http://en.wikipedia.org/wiki/Thermal_expansion_valve

 

I thought my explanation was good enough