can be used to charge a solar system. Its main ingredients are propylene glycol, a non-hazardous substance, also available in pharmacopoeial quality
and the food industry (E1520), cosmetics industry used in tobacco products. Recycled PET
in a bottle.
This antifreeze has been developed for systems that may contain aluminum, copper and iron components. Therefore, aluminum solar collectors can also be fitted with copper pipes. However, soft soldering cannot be used because zinc cannot be in the system.
Standard mixing ratio: 60% water for 40% antifreeze. That is, one and a half times as much water must be mixed with the antifreeze concentrate. This is about -23 ° C, corresponding to a freezing point. But it can also be mixed 1: 1 with water. Do not use tap water for dilution, as chlorine and who else knows what it contains and can cause electrolytic corrosion. Use distilled, osmotically purified, or possibly deionized water instead.
The antifreeze condition should be checked annually to prevent damage due to antifreeze acidification. This problem usually occurs with oversized systems, where in the summer of strong sunlight, the controller may stop the pump due to the high tank temperature and the antifreeze trapped in the collectors will heat up. But a multi-hour power outage in the summer sun can also be a problem.
Check with indicator paper . If the pH is between 6.9 and 7.5, the pH is adequate.
If this is not the case, the antifreeze mixture must be replaced. In this case, it is advisable to flush the system once or twice. About the exchange process here .
Required quantity table can be determined using.