How much maintenance do solar thermal systems require?

A oil boiler requires annual visits from your oil technician for cleaning and adjustment. Even a gas-based system should be cleaned every 5 years. Hot air furnaces have filters that need to be replaced quarterly.

In comparison a solar thermal system is “no maintenance”. Since we live in a “freeze zone” your collector will be filled with non-toxic, food grade Glycol instead of the actual water from your tank. A heat exchanger takes the heat, produced in the collectors, from the Glycol and warms the water.

In the summer your system often produces more hot water than you can use. This excess pent up heat causes the Glycol to break down and become acidic. This can cause damage to components of your system in contact with the glycol, including pipes, collector manifolds, pumps and heat exchangers.

Apricus recommends the Glycol be replaced every 2 years. Thermomax has a unique design (link to page Thermal cycle) in their tube. Each tube is fitted with a thermostat at the heat transfer end. When the glycol in the manifold reaches its maximum temperature, the thermostat closes, preventing the further transfer of heat to the glycol. Once the temperature of the glycol drops below the maximum temperature, the thermostat opens and the transfer of heat resumes. This helps reduce the overheating of the Glycol fluid thus prolonging its life.

For Thermomax systems we ask that you test your fluid (with a paper test strip) at the 5-year point to see if it needs changing. The replacement of Glycol is quick and easy. Our technicians will set up a convenient time and we are usually done in an hour.

Occasionally a tube can break due to thermal shock, large hail, or things such as baseballs. We have yet to have an installed Thermomax tube break (1/15/2009). A broken tube does not cause the system to “shut down”. A single broken tube has a negligible impact on system performance. A broken tube will still produce heat, but at a reduced level. Since the tubes just plug in, this is something you can do yourself, or we can have a technician stop by and take care of it for you. More information on broken thermal tubes.