Many regions seldom experience freezing temperatures while others deal with them much of the year. Chances are, if you live in climate where the temperatures drop below freezing frequently, the solar heater you purchased and installed is already geared to handle the changing conditions.Many of the regions that experience the coldest temperatures don’t lack sunlight during the winter, so ensuring that your solar hot water heaters functions year round is mainly an issue of freeze prevention.
First, the pipes, or as little as possible of them, should not be exposed. This is not as necessary if you operate a closed loop system with antifreeze. However, some closed loop systems circulate water as the heat transfer liquid which could freeze even during the day.
Closed loop systems pump a heat transfer liquid such as antifreeze into the solar collector. This liquid is heated by the sun and then pumped back to the storage tank where a heat exchange transfers the heat energy to potable water. Antifreeze will not fail during cold weather conditions, but you before the onset of winter you should check the amount of it. Any failure of the system during the winter could deprive your home of hot water.
water automatically drains out of the collector when there is no sunlight and no further water is pumped into it, drain back systems have a built-in freeze protection. If temperatures are below freezing even when the sun is out, drain back systems could still be at risk of freezing.