The Apricus solar collector is designed to be used with pressure up to 8 bar/116psi.
This means it is compatible with all low pressure, and most mains pressure domestic hot water systems.
In closed loop or sealed (dead water) thermal store systems an expansion vessel is often used to prevent pressure buildup as the water expands.
A pressure release valve should also be used as a safety backup.
In areas where freezing is not of concern, open loop systems are often used.
Open-loop systems are also appropriate for cold regions when used in combination with a Delta-T controller that incorporates a freeze protection feature.
Closed loop systems usually incorporate the use of a heat exchanger, either inside or outside the hot water storage tank.
Apricus solar collector are suitable for both open or closed systems, as long as pressure, heat and freezing are controlled.