A well designed radiant floor system distributes heat evenly over the entire floor area where you want and need it the most. A rise of 10 F in a concrete slab is the rough equivalent of a 40 rise in a 400 gallon tank. A properly sized heat exchanger and a three way motorized valve with the proper controls are all that is required to integrate the solar collectors with the radiant floor. A second smaller double wall heat exchanger may be added to heat the domestic hot water as explained in the Active Water Heating section. This type of system needs a large expansion tank to prevent over pressure during the summer months unless the heat generated by the solar collectors does some other job, such as heating a swimming pool.
Periodic maintenance is the same as given in active hot water heaters.
Due to the amount of collectors required, large home heating systems have always been the most expensive of solar heating systems. The use of used collectors cuts this initial investment dramatically. All of the recycled collectors we purchase are constructed of low iron tempered glass with copper waterways and aluminum or steel enclosures. Most of the equipment comes from large projects which were designed wrong or poorly installed. Diagram of Liquid System.