Hey guys, how are you. A question I want to ask. Load gas to a refrigerator of those that are showcases, which have glass doors. I went to the client's house I saw that he had 40% of his r134a gas load, I saw that he had the plastic service valve cover and not copper or bronze as he should have. Recharge, check with foam for leaks and find nothing. On the 4th day they call me that it doesn't cool anymore. I brought it to my house. And still with% load. I did not want to open the refrigerant circuit thinking that it should be the plastic cover, I reloaded gas walked perfectly for three days in my house and controlled by clock. About 90 psi with the engine off and rested. Then I thought that the problem was the plastic lid because I searched thoroughly with foam and found no leak. The condenser is two coiled aluminum spiral rolls, there I could not put my hand well, inside the spiral circle. How to detect the leak. I open the circuit in two and how many psi do I put? Can I put pressure with an external refrigerator compressor? leaving the equipment compressor disconnected and tightly closed? I don't have a large nitrogen tube to put in about 300 psi. please help.

Good evening friend, the recommended and professional in these cases is to pressurize the system with nitrogen, you can take it up to 150 psi and there you leave it for a few hours, many times it is left until a whole day and you notice if the manometer needle drops or no, if it descends then there is loss and you should look for it, either with an electronic leak detector or with a soap solution, but if it does not descend, then the leak takes place through the service valve, where you have the manometer installed, just change the Valve and ready, or else, after emptying and loading the system with R134a, you use a special sealer plier to seal and seal the service tube with autogenous welding, as all factory refrigerators come, in this case you will ensure that they no longer you will have a leak in that area, but you will not have access to the system, that is the only inconvenience, and if a problem arises in the future, you should use a pinch valve to be able to measure the work pressure Garlic. As for pressurizing with air, I can not recommend this, it is not professional, but if the client does not have resources to pay for this type of work and gives you the authorization to pressurize with air assuming the risks, well no way , do it, only then you should make sure that you have a good vacuum to the system, since the air eventually generates internally acids that will damage and shorten the life of the equipment.

Sucking the equipment is enough 100 psi to determine the luck leak

Thanks Fermín, that's what I did. Remove the damn aluminum spiral and I made a new spiral with copper pipe 1/4. It is so easy to work with copper. Haha. And yesterday I did that. I left him with psi. At three hours I remained the same. Today I get up and see 149 psi. Damn. It can't be said. I went to work half anguished. Then I remembered that the low ambient temperature makes the psi lower a bit. I came for lunch at noon and well! I was at 150 psi again. and I arrived at 18:00 and I emptied and charged gas. There is the team working at full capacity. what a joy At last. thanks to everyone. I do not like to close the problems because no one can comment. so he left it open a few days. Thanks again people.