AUTOMOTIVE R134a - LAND CRUISER 80 series

[syncview]

Hello everyone..

i'm new here and currently working on a car which is giving me a toughhhhh time.

the vehicle has three EVAPS, one on the front with a block type TXV, the fridge and rear unit has the traditional TXV with a 'remote bulb'

the system was originally a R12 system, but has now been converted to R134.

What has been changed:

front evaporator and txv
parallel flow condenser (from a serpentine condenser)
AC compressor SANDEN SD510
and of course R134a valves

All lines and EVAPS were flushed and old oil was removed completely.

currently the system is running with R134a, problem i'm facing is

if front is only used, cooling is perfect - no matter the vehicle or engine speed

if only rear in ON, cooling is again perfect, no matter the vehicle or engine speed

if both are ON together, front EVAP cooling goes south, >15 Celcius vent temps while the REAR UNIT works fine, <10 Celcius vent temps.

with both units ON, and vehicle running - the cooling gets better.
I've made sure that there is good airflow thru the condenser, i've made condensed foam duct between the radiator and condenser ensuring all air goes through the condenser, the mechanical fan has been set to partially engage at about 45 celcius and the condenser has two electrical high speed fans. so even at idle, there is a tornado going thru the condenser.


Fridge keeps working nicely all the time.

Pls see below table for further details, and pls also correct my SUPERHEAT and SUBCOOL calculations where needed

all temperatures are in CELCIUS
Pressures in PSI

EDIT: AMBIENT TEMP was 36C two inches away from condensor.

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