ThermaFlex Plate Heat Exchangers

Ancillary Items & Options

Control Valve: The control valve should be 2-port for steam and 2 or 3-port for water primary. A 3-port valve will maintain a fairly steady flowrate in the primary pipe-work whether the calorifier is using the primary water or not - this may be required on some systems. Control valves with a "double seat" to give higher throughput do not give guaranteed shut-off and should not be used for calorifier control.
High Limit Valve: If the control valve fails in the open position the calorifier will overheat. A high limit valve prevents this by shutting the primary fluid off if secondary temperature is excessive.
Pressure Relief Valve: Needed for all unvented calorifiers and where working pressure exceeds 25 m w.g.
Automatic Air Vent: Normally only needed on unvented systems.
Expansion Vessel: An expansion vessel should be connected to the cold feed pipe of unvented calorifiers.