Air con issue

[Shoes]

Wife has a 2011 1.3 Yaris 60k miles. Last year it developed an aircon fault no output. It had a regas when it was serviced. It worked last summer but this summer again no output. Took it to a specialist he said it has gas (showed me the equipment both dials on a blue and red regulater looking thing appeared to show pressure). He's said most likely it would need a new compressor around £500 for a reconditioned part fitted. Does this seem likely, could it be a blocked condenser? Thanks

[sh0rtlife]

AC systems are very simple devices...you have a pump, condensor, evaporator and a block for forcing presure
theres really only 3 things that can happen
no gas
dead/bad pump
bad pressure block

the blocks "can" gum up if you use off the shelf sealing refill kits
the evap can get pluged up but you would be overheating the car as well as air flows thru it into the radiator, ditto for the condensor, youd have no heat as toyota didnt realy isolate the heat from the ac in the box

[WeeYari]

When mine failed, it was due to a faulty $20 pressure sensor. I discovered this on my own after paying Toyota for an a/c diagnostic. They pointed to an issue with the compressor. Wrong!

[sh0rtlife]

When mine failed, it was due to a faulty $20 pressure sensor. I discovered this on my own after paying Toyota for an a/c diagnostic. They pointed to an issue with the compressor. Wrong!

actualy your right i forgot about that lil bastard too...i know there is a way to test it tho via continuity, if memory serves it should have continuity if there is pressure in the system, no cont if too high and no cont if too low

[komichal]

Mine AC - in hot days ( 30 oC or more) - takes up to 5 minutes before the cold air kicks in.
Had it in the shop (authorized Toyota service center) - they sucked away the refrigerant, vacuum-tested the system, added the refreshed refrigerant back, toped it up, measured pressures (all OK)... yet it did not help.

I had that pressure sensor changed as well - no improvement.

The verdict was "probably just tired compressor, we can change it to see if it helps but it will cost you a fortune". Nobody explained me what "tired compressor" means if all pressures are OK... so I gave up.

[sh0rtlife]

so let me clear the presures up

the system requires X pressure, and the sensor must see the pressure..something above 20 and below 45 psi
next the comp kicks on and builds pressure, anything up to around 200psi before being shut down

my question to them when they say presures are fine would be..to see what the "high side" is with the engine running....if your getting correct pressures on both high and low side then the comp is FINE

the bigger issue with "old cars" is that inevitable someone will have put some stop leak in which plugs the pressure control orifice plate and is useualy the cause of most of the issues..its this same stop leak that tends to kill the pressure sensor

after that the best thing i can say to do is see if both the condensor and evap are unobstructed..you could even have a bad blend door in the heater or cabin filter

the only other thing i can say is that the toyota specs for ac fill are not "correct" by the ac manufacturer specs, whereas you dont set the system for cooling at idle but you set it at 1500rpm