A closed system is created when there is a check valve between the water heater and the city water main.
Closed system water heater.
This is usually in the form of a bell shaped pressure regulator which is normal located very close to the water pipe s entry to the house.
When water heats it expands.
When the controller senses that the sun is shining and your tank needs a warm up it signals the pump to send water through the black collector panels.
When radiant heat is called for by the thermostat a pump comes on and circulates the warm water throughout the radiant floor until the thermostat is satisfied.
A water heater heats water that is constantly being replenished since it is connected to taps.
The heating fluid is self contained within the system and stays there unless removed for maintenance completely separate from the domestic hot water.
The heated water then flows into the storage tank before it s channeled into the heat exchanger.
A boiler is a device used to heat a home using steam and radiant heat techniques and is a closed system which rarely replenishes its supply of water from an external source.
If freeze protection is an issue than a closed system with anti freeze is a good idea.
The valves that are usually found in the closed systems are the check valve pressure reducing valve mixing valve backflow preventer and other.
Closed systems are often used in second homes or primary residences in areas prone to long power outages.
A closed water heater system means that the hot water cannot expand beyond the valves and mix with the municipal water.
Closed loop solar water heater systems sometimes referred to as anti freeze or glycol systems include the heat collectors insulated piping a circulating pump an expansion tank a hot water storage tank a heat exchanger solar fluid usually a solution of water and nontoxic propylene glycol antifreeze a controller valves and gauges.
All water heaters waste heat energy even when the burner is off and the unit is sitting idle between heating cycles.
The down side is two heat sources.
Closed loop solar heating system here s how a solar powered water heater works.
Some new water meters also have a check valve.