GENERAL FUNCTION (Special Settings for High Temperature System)
Water sourced heat pump system controller
The exeter XL System Controller is designed to manage a heat pump system water loop. By monitoring the water temperature, the controller can enable; heat injection or heat rejection devices to maintain appropriate system temperatures. The controller also monitors system water flow, and will enable a standby (lag) pump if the primary (lead) pump fails to initiate or maintain water flow.
Normal operation is indicated on the front panel by green LED lamps. Out of range conditions are indicated by red LED lamps and a 90 dB audible alarm. The front panel digital thermometer displays the system water temperature at the sensor.
After a power interruption or reset, the panel initiates an auto restart, there is a 3 second time delay to allow line voltage to stabilize. The loads are sequenced to prevent high inrush current.
On power-up or after a reset, the normally closed shutdown (N.C.S.) contacts are open. After 60 seconds, the N.C.S. contacts close and remain closed providing a temperature alarm or flow shutdown does not occur. The N.C.S. contacts can be wired to control the heat pumps. Use Com. and N.O. relay contacts.
The optional remote alarm provides an audible and visual indication of controller alarms. The audible alarm may be silenced, while the visual indication resets only with the controller.
PUMP CONTROL SEQUENCE OF OPERATION
The controller initializes the lead pump on start-up. Under normal operating….g…