Only perfectly clean and corrosion-free tubing should be used. All possible dirt should be kept out of pipes and components during erection. Copper pipe will be clean and sealed as received, and should be kept plugged at all times, except when making a joint. Use the plastic caps provided with the tube — they are easily seen and will not be left on the pipe. Plugs of paper and rag tend to be forgotten and left in place. Steel pipe will have an oily coating when received, and it is important that this should be wiped out, since the oil will otherwise finish up in the sump and contaminate the proper lubricating oil. If pipe is not so cleaned, the compressor oil should be changed before the plant is handed over.

Avoidable debris are loose pieces of weld, flux, and the short stubs of weld­ing rod often used as temporary spacers for butt welds. Pipe should only be cut with a gas torch if all the oxidized metal can be cleaned out again before closing the pipe.

It should be borne in mind that all refrigerants have a strong solvent effect and swarf, rust, scale, water, oils and other contaminants will cause harm to the system, and possible malfunction, and shorten the working life.

Posted in Refrigeration and Air Conditioning