Rainwater Collected from Roofs - Solar Collectors - Underfloor Heating

Rainwater collected from roofs fills the underfloor heating circuits and solar collectors

This was not an arbitrary decision, on the contrary, to maintain the life of the metal components of these circuits, we must prevent the corrosion that desalinated water system would cause.

In order to reduce bottled gas consumption, in June we incorporate solar collectors occupying an area of 12m² to maximize use during the season from September to April, which is the time when our lodge is open. For this we built a surface/roof at the back of the inn, north facing, with a 35 degrees slope, the optimum angle for use in the season.
To store the hot water, we installed a 1,000 liter thermal tank, which has an output below and an input at the top, where it is connected in series, with all inlet manifolds below, and exit ones at the top.

The whole circuit is completely filled with rainwater and powered by solar radiation entering through the collectors surface, heating the water inside, based upon the physics principle, which states that hot water, being less dense, ascends, and the cold water descends. This condition moves the water without the need for a circulator; warmer water rises inside the manifolds and enters the thermal storage tank, displacing cooler water located at the bottom of this tank into the inlet manifolds, creating a continuous circulation of hotter water into the storage tank.
One of the biggest challenges we must overcome to preserve intact the investment in solar collectors, is prevent the corrosion caused by using the desalinated water offered by the mains water of Puerto Piramides.

For this, we installed two heat exchangers in series. The heat exchangers are metal devices for the dual circulation of water. They are small, the largest one measures 30 cm x 7 cm x 5 cm and are designed to transfer heat between luids circulating within two circuits. In this particular case, we move warm rain water, accumulated in the tank, to heat, on the other side, the water we need to warm. We have two choices depending on the time of year where we are. By opening only two valves and closing two other valves, we open a circuit and close the other one, deciding if we want to transmit the heat to heat desalinated water or to the boiler for the radiant floor that also have rain water.