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ankur meno
20-04-2020, 12:20 PM
Long story short, 15 year old Samsung french door refrigerator. Fridge section stayed at 38 but freezer was 62. Hooked up an envirotech 3226 to it using a supco piercing valve and it was -28psi. Filled to 0 psi and waited overnight. Told the fridge to keep the freezer at -12 but it’s holding -2f (using a thermometer). Used 1/6 - 1/5 can of 12oz r134a. 2 bhk in thane (https://www.ashwinshethgroup.com/project/)

Waited 24 hours and checked today again by hooking up the envirotech discharge hose to the supco bullet piercing valve and it showed -8psi. 3 bhk flats in dadar (https://surajestate.com/2-3bhk-flats-suraj-palette-dadar.html)

Did it drop because the system got cold? Or am I losing refrigerant?

frank
20-04-2020, 02:46 PM
The only way to know if you have a leak is to de-gas the unit and pressure test with OFN

NH3LVR
20-04-2020, 06:45 PM
Domestics are not my specialty at all.
It seems to me that 1/6 - 1/5 can of 12oz r134a would not be enough to charge the unit though.

nike123
25-04-2020, 09:26 PM
Domestic refrigerators at R134a, after some years of use, especialy at hot ambients, have tendency to clog capillary tube. Symptoms are almost same as refrigerant leak.
If adding refrigerant did not permanently helped, And there is no leak, than you probably have chance of cloged capillary tube which need replacement.
Measure compressor current along with pressures and see if current is high while suction pressure is low.

Find data about current consuption for your compressor.
Low pressure with below 80% current for that pressure mean refrigerant leak.
Low pressure with normal or slightly higher current mean cappilary restriction.

Best way to find out is to recover refrigerant, charge it to nameplate again and then check pressure.

There is no such pressure as -28psi. It could only be -28inHg

coolguy4
13-05-2020, 01:32 AM
It does. Small systems such as refrigerators are also very sensitive to the charge amount, it's hard even for an experienced tech to get the charge right by pressure alone. The best and easiest thing to do would be to remove all the refrigerant in the system and weigh in the correct charge, which will be listed on the unit's spec sticker, probably inside the refrigerator.