Refrigerant Charge

The charge depends not only on the compressor, but also on the size of other system components.

Please check the name plate of the machine. Sometimes it contains the details of Quantity of refrigerant in the system. If you want to calculate the refrigerant charge there are many factors like capacity,type of refrigerant,volumetric capacity, efficiency etc. For most practical applications details are taken from the name plate of the machine if the name plate is in good condition. Otherwise you have to refer the operation and maintenance manual. Regards, Dr.Ram.

Is it possible you are looking at Locked Rotor Amperage rating?

I have charged systems with unknown refrigerant volume by creating a "worst case" heat load (both evaporator and condenser) and watching the compressor current draw to get it close to FLA (full load amps.).

Another way is to install a sight window.

LRA140 stands for Locked Rotor Amps 140. That is an electrical rating.

You look like you are in over your head. A refrigerant charge is weighed in as per the origional design plate on the equipment. Or if it is a built up system; it is based upon several factors, such as load, application, subcooling, superheat, etc. It would not hurt to know what refrigerant and type of compressor oil you need.

YOU HAVE TO KNOW WHAT THE REFRIGERANT IN THE SYSTEM IS. IF YOU DON'T BUT IT IS COMMON TYPE OF OPERATION, THE OIL ON A SMALL COMMPRESSOR OF THIS TYPE IS IN THE MODEL # AND YOU CAN GET THAT FROM THE MANUFATURER. IF IT'S ESTER OIL ITS A HFC, IF IT'S ALKYL OR MINERAL OIL IT'S HCFC OR A BLEND. IF THERE IS REFRIGERANT IN THE SYSTEM YOU CAN PULL IT INTO A RECOVERY CYLINDER AND LET IT SET OVERNIGHT AND MATCH THE PRESSURE TO A TP CHART. AFTER YOU DETERMINE THE REFRIGERANT CHARGE IT BY SUBCOOL IF IT'S AND EXPANSION VALVE(14-16' DEGREEES F WILL WORK), USE SUPERHEAT IF IT'S A FIXED ORIFICE OR CAP TUBE SYSTEM. I WOULD PROBABLY USE THE SAME TEMPERATURE RANGE IF IT'S A/C OR MEDIUN TEMP REFRIGERATION, YOU WILL PROBABLY END UP LOWER IF IT'S LOW TEMP. IF ITS ON ACHILLER LEAVE IT ALONE AND CALL FOR SERVICE BECAUSE YOUR QUESTION INDICATES THAT YOU MIGHT BE IN OVER YOUR HEAD. ( YES I KNOW ABOUT CAPS BUT CAPS LOCK IS ON.)

WELL, TURN IT OFF!!

i was most of the way through it and it was apparent from the wording that if the man tried it himself, disaster was imminent so i didn't think it was worth retyping.

Sorry if I was a bit abrupt there. Some word processors have a feature that lets you undo all-caps after the fact, but I think you then have go through once again and restore the items that should be capitalized.

Many drawings, especially older hand-lettered ones, used all-cap text. Maybe this is what seduces engineer posters into thinking all-caps are okay (or simply not noticing). Most engineering writing should be done in plaintext, with only occasional words highlighted. Too much fooling around with italics, underlining, boldface, weird fonts, and colors is mostly distracting.

Thanks for reacting with grace!

--That's my "Editor Crankshaft" persona talking.

tornando, i see your postings and appreciate your input to cr4. i own a commercial industrial mechanical service company in another state and cr4 is one of my daily highlights.your posts add alot and i thank you. we install and service bac's and pneumatics as well as equipment service. i am convinced that this country will not servive as is if the current generation doesn't assume more initiative and decide that economys are based on production which includes best quality and value. this rerquires automation which i believe could be the countrys savior. i have long intended to add industrial automation to our capabilities but i have lost most of my industrial base because the states of nj and ny made it impossible to manufacture in those states. before i give up the ghost i would really like to be a part of a manufacturing comeback. my 2 main guys, whom i hope to pass the business on to, are starting to grasp that the money we earn is not what makes us worthy or better than the competition but merely the score card in a less than admirable league. satisfaction and self worth comes from creativity and accomplishment in a worthwhile field playing in the big leagues.

any thoughts about the sanity of my ideas by you would probably be of real value and weigh in my deliberations.

I am not closely familiar with the industrial climate in NY and NJ, but from what I have heard, your impression seems sensible.

I agree too that we are losing too much of the manufacturing/production side of our economy.

You would almost surely enjoy Samuel C. Florman's book, The Existential Pleasures of Engineering.