Notes for Private Cool-store Owners.

New Zealand Journal of Agriculture, Volume 57, Issue 6, 20 December 1938, Page 542

Notes for Private Cool-store Owners.

Cool Storage Notes.

cool stores are now emptying FRUIT and many of them have out, and many of them have already closed down for the season. When the refrigerator has had its last run for the season all glands of stop and expansion valves should be tested with a spanner for tightness. The main delivery and suction stop valves of the refrigerator should be closed, to avoid filling the crank-case with liquid ammonia. A piece of white material should be tied to the delivery valve to indicate to the operator that the valve has been closed and must be opened again before starting up the refrigerator. The main fuses should be removed from the switchboard, so that if the switch is operated the refrigerator is unable to start up. This is a precaution against some unauthorized person tampering with the - starting-switch. With the delivery stop valve closed, the end of the cylinder would be forced unless a high-pressure cut-out had been fitted. On closing down the plant for the season the first duty is to clean all fruit

out of the chambers as soon as the temperature' begins to rise above 45 0 F. The floors should then be thoroughly swept. This is the time to scrape and paint the ammonia coils. A second-hand bicycle-chain wound once around the pipe and pulled both ways is ’ a quick and effective method of cleaning old paint and rust from coils. Aluminium paint is largely used for this class of pipe, and paints with a zinc base are also recommended. Engineers are finding that waste refrigerator oil sprayed on to the coils with a spray-gun is most effective in checking rust, as it soaks through the rust, which falls off with the frost when the cooling begins. : The only drawback to this method is that the rust is inclined to block the traps in the drain-pipes. The scraping and cleaning-out of rust is therefore recommended before spraying takes place. Waste refrigerator oil . is also quick and effective -in dealing with mould on lining-timber in. cool-storage chambers.

■»' Inspection of the Glands. Before starting up for the next season’s run, arrange with your refrigerating engineer to repack the gland of the main suction stop valve and to inspect the glands of the expansion valves, The refrigerator valves should also be overhauled at this time of the year. Oilstrainers are likely to block if not frequently inspected and cleaned. This also applies to scale-traps. The con-densor-pump should be thoroughly overhauled, as it is a most important part of the refrigerating plant. The fuses on the power ' switchboard should not be allowed to overheat. If this,' occurs, the electrician should be notified before further trouble develops. Leave the chamber doors open during the shut-down period, to allow fresh- air to keep the chambers fresh until they are to be used again for storage.

—A. Powell,

Cool-storage Officer,

Wellington.