front A/C is cooler than the rear

[ravelcop]

hindi pantay ang lamig ng front and rear A/C ko. what could be the probable causes aside from the difference in evaporator coils? sobrang lamig ng front A/C ko compared to the rear A/C. both of them naman were cleaned at the same time, last month lang. as a matter of fact, yung evaporator coil ng rear A/C is the one used in Nissan A/C system

[acenie]

Ano ba ang sasakyan mo, pa check mo yung Solenoid Valve sa Rear Aircon baka barado na.

[ravelcop]

Hyundai Galloper po, the re-badged Pajero boxtype. i remember my technician told me before na tinanggal nya daw yung solenoid valve, so kahit naka-off yung rear A/C, nag-cicirculate parin ang lamig on both front & rear coils.

another technician told me na dapat daw front and rear expansion valves are the same para pantay ang lamig, how true is this?

[mbeige]

Nakabukas ba vents sa likod?

[abort_retry]

that is the side effect of removing the rear solenoid valve. hihina talaga lamig ng front and rear a/c mo. actually malamig rin naman ang front kaya lang it is cooler if there is a rear solenoid valve installed. kasi it cut-off the flow from the rear evaporator when not in used..... buy a new one and have it installed. hindi naman kamahalan siguro ang part na yan dahil P900 lang kuha ko when i replace my starex's rear solenoid valve.

[ravelcop]

i dont understand how the valve affects the coolness of the rear A/C? diba you said its only purpose is to cut off the flow kung hindi ginagamit ang rear A/C? so without this, it's free flowing from front to rear. kaso ang rear A/C ang hindi masyadong lumalamig kahit free-flowing sya, yet there's nothing wrong with the front A/C, it's soooo cold. could there be any other culprit?

[abort_retry]

the solenoid valve at the same time is a one way valve. dahil hindi makakabalik ang refrigerant on its reverse direction, the rear evaporator gets more than enough cooler refrigerant that passes by the rear condenser. malamig pa rin naman both front and rear kahit walang solenoid valve. pero masmalamig kung meron nito. probably in addition to your problem, the rear expansion valve is defective or the nissan evaporator coil is not matched to cool down the rear cabin. maybe konti lang ang rows ng coil which in effect gives lower level of coolness. how about the rear condenser, nilinis din ba?

[ravelcop]

isang napakalaking condenser lang po meron. kasing-laki ng radiator which is also mounted infront of the radiator. yung gamit nyang evap coil is yung stock ng nissan, not the jap replacement. one more thing is sobrang lakas ng rear blower, naka HIGH palagi coz sira na ang control. pero kahit nilakasan ko rin ang front blower and compared the two, maslamig parin ang front, the difference is really obvious

[acenie]

bakit sa akin inalis din yung Solenoid Valve sa likod ok rin malamig naman

[abort_retry]

then probably the problem is either the rear expansion valve or the rear evaporator.... baka hindi kaya palamigin ng maayos ang rear cabin due to the evaporator. dahil bagong linis naman you are sure that the a/c line and hoses are ok. compressor is ok rin dahil malamig naman ang front...

[derfoj]

I'm having the same problem right now with my hyundai grace, technicians say the culprit is the compressor.

Now, how do I know that the compressor is really malfunctioning?

TIA

[ravelcop]

done replacing the rear expansion valve but to no avail, ganun parin. my only suspect is the rear evap coil

*derfoj
i dont think your compressor is the culprit. as Abot_Retry stated, if your front A/C is working well, then the compressor must be working well also since napapalamig nya ang front

[sentra98]

i have another problem naman, iyong rear a/c ko hindi kaagad sumasabay sa harap pag-on. may delay ng mga 5 mins. ano kaya prob?
hyundai grace po ride? TIA

[afrasay]

Dati ba malamig yun rear aircon? if expansion valve ang sira, walang lamig na lalabas sa rear puros hangin lang. the solenoid or shut off valve only shuts off the freon/oil flow sa rear evaporator to prevent freezing of the cooling coils. any difference in the cooling effect either on or off is negligible. kung gusto mong lumamig yan install a separate condenser for the rear aircon. nga lang baka di na kayanin i-pump nun compressor yun added freon and oil.

[derfoj]

Dati ba malamig yun rear aircon? if expansion valve ang sira, walang lamig na lalabas sa rear puros hangin lang. the solenoid or shut off valve only shuts off the freon/oil flow sa rear evaporator to prevent freezing of the cooling coils. any difference in the cooling effect either on or off is negligible. kung gusto mong lumamig yan install a separate condenser for the rear aircon. nga lang baka di na kayanin i-pump nun compressor yun added freon and oil.

In my case, Hyundai Grace already have two condensers still the same thing is happening.

I have brought it to a good ac repair shop (as per the forums here), and they did the following:

1. Cleaning/leak test of two evaporators and testing of compressor.
2. Change 1 of the two hoses connected to the compressor.
3. Change drier and 2 expansion valves.
4. Change some of the fittings.
5. Cleaning of two condensers via high pressure water.
6. Cleaning of air ducts on the rear.
7. New line and switch for the rear motor.
8. Change from R12 to R134a.

After correctly charging the freon they tested the ac and to my surprise the rear has a lot of wind but no coldness.

They told me that the compressor needs to be changed.
I thought WTF! They tested the compressor and told me that it was ok and now they are telling me otherwise.

Before I forget, I paid PHP8500 for their service and left the shop very dismayed.

I felt that I did some unnecessary spending that day.

That is why I will try to visit other ac shops just to get their opinion and to avoid spending unnecessarily.

Any information, idea, help and suggestion from fellow tsikoteers will be highly appreciated.

Again TIA.

[afrasay]

may thermostat switch ba yun rear aircon?

[derfoj]

may thermostat switch ba yun rear aircon?

Afrasay,

Not sure about that.

Anyway I'll be back tomorrow to their shop to have another check and replacement of expansion valves. Will try to ask them about the rear thermostat switch.

Good part is it will be for free as per the owner.

I'll keep my fingers crossed.

Nawa'y patnubayan tayo ng MAYKAPAL sa ating paglalakbay.

[derfoj]

Afrasay,

The van only has one thermostat.

Anyway, the ac is ok now after replacing the compressor with a new one and after another 18K more or less of spending.

Nawa'y patnubayan tayo ng MAYKAPAL sa ating paglalakbay.

[Dudee]

Guys, post din ako prob ko. sana may makatulong.

Recently my rear A/C of adventure loss it's coldness. Culprit was the expansion Valve, so pinalitan ko na. After replacing, everything was fine not until after 2 months...

Problem is this. If the Rear A/C is On/Open, the Front A/C losses it's coldness. Kung closed/Off ang rear A/C, malamig ang Front A/C. The shop here guess and told me na nag-aagawan daw ng Freon/Coldness ang A/C, and HE DOESN'T KNOW HOW TO FIX IT!!!!

EVaporator is Free from leaks Drier is fine.

Help naman...

[afrasay]

kulang sa freon yan.