SOLAR WATER SYSTEM – HOW IT WORKS 

Typically 20-30% of a home’s energy use is to heat water for showers, laundry, dishwashing, etc.  Solar water heating can provide 70-80% of your hot water.  Water or glycol (anti-freeze) is pumped to the collectors during sunny days.  Heat is transferred from the collectors and stored in a tank for use when you need it.  The system turns off automatically at night or in very cloudy weather.  The system automatically prevents freezing of the pipes during winter.   There are two types of systems, drainback and glycol (anti-freeze).

• Drainback type:  Water is only circulated in the exposed piping and collectors when the temperature in the collectors is hot.  At night time and cloudy days, the system is off and the exposed pipes are empty, which prevents freezing.  The collectors must be located above the storage and drainback tank.   This system will not overheat in summer.

• Glycol type:  At night time and cloudy or snowy days when the system is off, the pipes stay full of the glycol solution.   Special controls are used to prevent this system from overheating in the summer.

Solar Space Heating