Converting from R12 to R134a

**miked** · October 11th, 2014 02:40 PM

This is more like an LTO registration issue.

i have to admit R12 yung system ko. but by the time na nagrehistro ako ng sasakyan e mahina yung A/C. nirason ko na lang na di ginagamit ang A/C. sa pananalita ng LTO inspector, mukhang gusto nya ako huthutan ng pera dahil non-A/C nakasaad sa rehistro ko. nirason ko naman na reyna ng garahe sasakyan ko most of the time. kesyo kelangan ko pa daw ng certificate from A/C shops na magpapatunay na R134a nga dahil bawal na daw R12, etc.

pero gusto ko rin syempre na magamit pa rin yung A/C ko. so ang tanong lalu na sa mga nakaexperience neto ay may kelangan bang palitan na major part (comp, cond, evap, drier/filter, hoses)sa A/C when converting from R12 to R134a?

i have read somewhere before na yung o-rings for r12 ay hindi compatible sa R134a, etc, etc, blah blah.

**bigfoot2000** · October 11th, 2014 02:57 PM

Its a different gas that may not be compatible

**ParticleX** · October 11th, 2014 03:51 PM

Change compressor na lang since sabi mo mahina na rin ang system. Pwede mo pa ring ibenta ang luma sa mga AC shops.

Full flushing lahat ng tubes, condenser, evaporator. New drier and expansion valve

Yung sa akin dati pinaconvert ko rin sa 134a pero intermittent ang lamig. Pinatignan ko sa Petron dito sa amin kasi parang may computerized gas analyzer sila for AC, may halo pang at least 15% na R12 at ibang flammable gases yung sa akin (di siguro na flush ng mabuti)

**miked** · October 11th, 2014 05:14 PM

Originally Posted by ParticleX

Change compressor na lang since sabi mo mahina na rin ang system. Pwede mo pa ring ibenta ang luma sa mga AC shops.

Full flushing lahat ng tubes, condenser, evaporator. New drier and expansion valve

Yung sa akin dati pinaconvert ko rin sa 134a pero intermittent ang lamig. Pinatignan ko sa Petron dito sa amin kasi parang may computerized gas analyzer sila for AC, may halo pang at least 15% na R12 at ibang flammable gases yung sa akin (di siguro na flush ng mabuti)

ganon? palit compressor agad dahil sa mahina? i had it pressure tested last time e ang sabi mahusay pa ang compression sabi nung AC tech. i actually have a thread with regards to this problem.

**jick.cejoco** · October 11th, 2014 05:53 PM

to check compressor integrity, run the engine with the compressor clutch engaged at at around 2500 rpm, the suction pressure should drop below 28 psig. to check the high side, unplug or disable the condenser fan. the pressure should rise to around 200 psig at idle, around 230 or higher at around 2500 rpm. to retrofit, remove the compressor and drain the oil and replace with either polyol ester (POE) or polyalkylene glycol (PAG) oil. change the receiver drier to X7, change all the o-rings to the green ones (HNBR)and change the thermostatic expansion valve designed for R134a. add more airflow to the condenser by either to a bigger CFM fan or add either a pull or push fan whichever is applicable.

**ParticleX** · October 11th, 2014 05:59 PM

Di naman necessary, para less hassle lang in the future. It could leak kasi as I understand R134a molecules are smaller than R12.

Change seals, o-rings, old oil from your compressor to R134-compatible.

**miked** · October 11th, 2014 09:27 PM

now i know. marereckon ko na ang gagastusin. salamat sa inyong lahat.

**miked** · October 11th, 2014 09:30 PM

Originally Posted by jick.cejoco

to check compressor integrity, run the engine with the compressor clutch engaged at at around 2500 rpm, the suction pressure should drop below 28 psig. to check the high side, unplug or disable the condenser fan. the pressure should rise to around 200 psig at idle, around 230 or higher at around 2500 rpm. to retrofit, remove the compressor and drain the oil and replace with either polyol ester (POE) or polyalkylene glycol (PAG) oil. change the receiver drier to X7, change all the o-rings to the green ones (HNBR)and change the thermostatic expansion valve designed for R134a. add more airflow to the condenser by either to a bigger CFM fan or add either a pull or push fan whichever is applicable.

the problem is that it does not have an service valve on the high side. only on the low side. cycling clutch system.

the AC tech actually did what you just mentioned, but without a tachometer. he said the compressor is ok that time based on the suction reading he made.

**miked** · October 11th, 2014 09:36 PM

Originally Posted by jick.cejoco

to check compressor integrity, run the engine with the compressor clutch engaged at at around 2500 rpm, the suction pressure should drop below 28 psig. to check the high side, unplug or disable the condenser fan. the pressure should rise to around 200 psig at idle, around 230 or higher at around 2500 rpm. to retrofit, remove the compressor and drain the oil and replace with either polyol ester (POE) or polyalkylene glycol (PAG) oil. change the receiver drier to X7, change all the o-rings to the green ones (HNBR)and change the thermostatic expansion valve designed for R134a. add more airflow to the condenser by either to a bigger CFM fan or add either a pull or push fan whichever is applicable.

how about the hoses?