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Howdy everyone I'm new here and I have a 2013 Hyundai accent gls with a 1.6l engine. Well the issue I have is the a/c is barely cold Durning the day but at night is ice cold, and by barely cold maybe not even cold but more hot and humid at times. I live in Arizona, so it's pretty hot in the summer here, I have replaced the compressor, desiccant bag because it's built into the condenser, and expansion valve. No leaks on the refrigerant and was vacuumed it down for 45 mins and it held vacuum for 30 mins with no change and it was properly charged with r134a. I'm just trying to figure out what is causing my a/c to not work during the day.
Living in a cold damp climate I don't see that many AC problems you have covered almost all the possible causes but some ideas ---
With the AC off and the heater set to cold is the air coming out the air vents at close to ambient temperature ?---( thinking heater flap issue).
Also I have seen cars with the air sided of the condensor radiator choke anything that reduces the airflow through the condensor such as a the fan not coming on when the AC is will reduce the efficiency of the AC
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Thanks for reminding me yes I did check the blend flap for heat and it's ambient fresh air coming in with heater to cold, also I pulled off condenser and back washed the fins off, so I know it's not an air flow problem. Also fans come on too first thing I checked.
I've kinda done some research and just trying to verify but I'm not sure if this car has a evaporator temp sensor that could be faulty or where it's even located. It's hard to do checks and stuff because I'm hardly home because of my job, being an over the road truck driver.
Last edit: 6 years 8 months ago by Madmax245. Reason: Forgot to add something
The day/night issue is making me think the ecu is seeing an over pressure and not enaging the compressor clutch. With the AC on try checking there is 12v supplied to compressor clutch. You could check the rest pressure of the system engine off car cooled to ambient temperature with R134a this normally very close to the ambient temperature in Farenheit. The running low side - high side can be found here
www.rechargeac.com
chart
together with a fault finding table based on pressure readings.
If the pressures are okay then try a by-pass to supply 12v to the compressor clutch --- I would probably do this by by-passing at the relay (take care to jumper the correct terminnals). If this produces cold air suspect the pressure sensor .
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Well one thing i do know is there's only one switch on the lines and it's on the smaller diameter ac line. I know compressor works fine and works when it's doing this weird issue, rest pressures are perfect and when the AC is working pressures are perfect too as I was the one who charged it and did all the work.
Also should note when it's doing the weird problem the high side acts like it's going high and shutting down then comes back to normal, cause parts diagrams and from what I've researched I'm thinking it's the evaporator temp switch and it could be faulty and it's reading like it's freezing up, but I know it's not. I'm just trying to see if I'm going in the correct direction with this
Last edit: 6 years 8 months ago by Madmax245. Reason: Word correction
Andy.MacFadyen wrote: The day/night issue is making me think the ecu is seeing an over pressure and not enaging the compressor clutch.
I am thinking the same thing. Have you checked the pressure transducer.
I'm not sure if this car has a evaporator temp sensor that could be faulty or where it's even located.
Yes, it does.
"Knowledge is a weapon. Arm yourself, well, before going to do battle."
"Understanding a question is half an answer." I have learned more by being wrong, than I have by being right.
Sounds like a bad txv. When the high side went high did the low side go low at roughly the same time? Why was the compressor changed?
The first thing people do when their a/c doesn't seem to be cooling is go to the store and buy a can of refrigerant with sealer because it's what joeys uncles brother did and he said it fixed it. The sealant will clog the receiver/drier, coat the lines, sticky up the txv and then when the Desicant gets liberated gets stuck in the lines. So, if you didn't flush the lines some crap might have found its way in to your txv or just a bad txv. Glad you changed the condenser, you can't really flush the new ones out. Also, if you used the little cans and didn't purge between cans it's possible to get air in the system giving you high pressure with low cooling. Feel both lines at the firewall should be roughly the same temp.
Rockyroad wrote: Sounds like a bad txv. When the high side went high did the low side go low at roughly the same time? Why was the compressor changed?
The first thing people do when their a/c doesn't seem to be cooling is go to the store and buy a can of refrigerant with sealer because it's what joeys uncles brother did and he said it fixed it. The sealant will clog the receiver/drier, coat the lines, sticky up the txv and then when the Desicant gets liberated gets stuck in the lines. So, if you didn't flush the lines some crap might have found its way in to your txv or just a bad txv. Glad you changed the condenser, you can't really flush the new ones out. Also, if you used the little cans and didn't purge between cans it's possible to get air in the system giving you high pressure with low cooling. Feel both lines at the firewall should be roughly the same temp.
Alright there was never any sealant used in the AC system, the compressor was diagnosed failing by a shop, hence new compressor, condenser was not replaced because the receiver driver is built into it but can change the descant bags out through a plug, and the expansion valve was replaced as well, manifold gauges was purged every time can was swapped so no air in system.
As I stated I'm am over the road truck driver, so I haven't been home yet to do some checks on the evaporator temp switch or even the one on the AC line, also gonna check fan connection for the AC and rad fans as I've heard some people with Hyundai's having some bad weather pak connectors causing a high resitance. Also when high side would go high the compressor would cycle off it would drop down and come back on. Also when it does this it affects the throttle of the car, like surging to describe it
To note did this same thing after my fiance took it to have evacuated and recharged before I replaced the parts they told her was going bad
Ok, still sounds like a faulty txv. I read that you just replaced it, but they can be bad out of the box. Let's just think about this logically. While everything seems to be running normally you see the high side do something wonky, it goes up in pressure somewhat erratically quick seems to stall out,then back down. Is it hitting the high pressure cutout? Probably not if the compressor clutch stays engaged. That leaves some kind of restriction. Unless, at that moment the electric fan kicks off and on, I'm assuming not. So, you have a compressor,high side discharge line to condensor to receiver w/desiccant, high side to txv,evaporator, low side suction to compressor. I'm gonna go look up your system I'll be back. But as of now without actual low and high gauge readings with outside temps I'm gonna say txv.
Looks like a pretty simple system, nutnfancy.
I guess you answered some of your own questions,as far as checking fans. Just some food for thought, your high side pressure going too high can really only be a couple things either a restriction,no air flow over the condensor or over charge and/or air in the system. Forget about the cycling switch on the evap, it shuts the compressor off when evap gets too cold. You get cold at night. What changes? Outside temp. Not having a fan on the condensor or any air flow from sitting still,it won't be able to transfer the heat out of the refrigerant . Get the hose and blast it with cool water, if you get cooling back with good pressures then look closer at the fan and don't forget about the relay. Sometimes fans start to shit out drawing to much amperage and kill the relay as well as melt the connector. It appears your high side cutout is working fine, that should be the switch on the line. If none of the fan stuff works we'll have to start looking at possible restrictions. If you have a point and shoot temp gun you can scan the system for an abrupt cold spot-possibly non engineered restriction. Just a thought, did you drain all the oil out of that new compressor and measur?
At night time in Phoenix AZ is still 80+ degrees, I know airflow should be great I sealed off the AC line ports and back washed to fins on the condenser. And yes drained all oil out and put correct amount in even after blowing out evaporator without expansion installed and all lines to get oil from the system out, even did condenser before new desicant bag.
You must play piano or something, quick with the keys. Aren't you supposed to be driving? Must be at petro having brunch.
Ok, so your high side is spiking and shutting the compressor off. If you have it running max ac and the fans not on you have a restriction. If you can't find a cold spot on the condensor or don't feel a cold spot on the lines it's the txv. The lines at the fire wall should be ROUGHLY the same temp, discharge to compressor a little colder. Whenever your dispatcher decides it's ok for you to go home we can revisit this after you check out a few things.
Nope never played piano, also using my phone to access here, and the food there is terrible I cook my own on the truck lol but currently waiting at my delivery until tomorrow morning. But yes I need to get a non contact thermometer and get home to do some tests which should be this week and I'll get some video of the gauges and things
Sounds good. Sucks you're stuck there till tomorrow tho. Must be electronic log. I'm still using loose leaf, for now anyway. Just need a couple more things to get back in diagnostics full time and get out of the truck.
