69NT40 low suction pressure and oil don't come back to carter

[mikashipping]

Hello good day!
I have a reef container and some problems was founded
The oil don't come back to compressor (06D semihermetic) and fix in the receiver
I clean the system with R141 and nitrogen change the oil,filter dryer and txv
after proced a vacuum about 3 hr and charge the system with 3,8 kg R134 (charge
Specific at plate) about 30 min the oil was noted in the condenser and the suction pressure is -06 psi and little ice at service valve
Is normal this pressure ?
This container is used for provision frozen for meat and chicken -18C
Some times the dor is open (comercial reef chamber dor)
and the temperature don't come below -12.6C
Thanks in advance
Best regards

[reefermechanic]

hi mikashipping,

i was seen same problem about 2 months ago. We changed TXV, dryer,compressor and also receiver tank. Our unit was worked properly. Everythings ok.

But i think your unit is not working properly. First when you seen suction pressure -06 psi? Return temperature how many? Also you have to check SMV and TXV Quench valve. Have you check them performanceses?

see you

reefer mechanic.

[mikashipping]

Yes, I'm check now the temperature was -14C and pressure is 0 psi but have little oil in receiver and I. Fix the time defrost in 6 hr I think this txv isn't original because the metal is diferent color
Here in brazil is very difficult to found alco valves
I try to clean again all the parts, if not success , I replace that for danfoss TLE 5
Thanks

[reefermechanic]

Hİ MİKA

pls say the model number to all. For exp. 69NT40-511 etc.

see you

reefer mechanic.

[mikashipping]

69nt40-511-52

[reefermechanic]

hi mika

pls check pm.


see you

reefer mechanic.

[mikashipping]

Hello Srs now the system is better, but the oil don't come to the compressor, the temperature come to -16.7 C I change the txv for a danfoss TEN5 and the temperature fix between -15 to -17 and the oil Return more quickly, but in receiver tank, about 1 hour after defrost, I note oil in lower glass now in brazil the temperature is 23C and the fan condenser start and stop sometimes 8 bar stop and start 13.9 bar at this pressure the oil an refrigerant go to upper glass and after defrost that oil return to Carter I'm clean the system again after solder the txv was made another vacuum about 2 hous and charge with R134a
At -17C the suction pressure fix at -1.98 psi I think this pressure isn't normal
after I bring more news because I'm send this for iPhone

Thanks in advance

[aussiereefertec]

when the unit is running at a low temp the back pressure can be in a small vacuum your oil return sounds fine can u put the unit through an AUTO2 pretrip and see if it passes

[bruisermac]

how are you meeasuring the oil return? Did the compressor have the correct oil charge to begin with? An O6D takes just shy of 4 litres top get to the bottom 1/8 of the glass.