DHW Recirculation Pump Option

The domestic hot water circulation pump is an available option within the unit. The pump is added to minimize delay in the delivery of domestic hot water at the draw off point in a closed DHW circulation circuit. It is generally used in systems where the domestic hot water needs to travel greater distances to its draw off point. Adjustments to the pump settings should be done by recognized personnel only.

Status indicator LED

LED on (continuously):	Normal operation (pump is running)
LED blinking short, long:	Error due to low voltage
LED blinking short (4x), long:	Error due to pump speed feedback
LED blinking short (3x), long:	Error due to high temperature
LED blinking short (5x), long:	Pump rotor is blocked
LED On 200 msec., Off 200 msec., On 200 msec.	Air venting
LED On 50 msec., Off 50 msec., On 50 msec.	Stand-by

Operation errors

Problem	Cause	Solution
Pump not running	Not connected or connected correctly	Connect correctly
	Pump too hot, dry operation or overheating protection active	Allow pump to cool down, pump restarts automatically
	Pump is blocked	Contact your supplier
Pump is noisy	Not thoroughly air vented	Air vent the pump
	Foreign objects in pump	Contact your supplier
	Worn bearing	Replace pump

	Air venting the pump The pump has an air venting function that can be activated by turning the knob to position 7 for 5 seconds. Afterwards the desired position can be chosen. The procedure will take about 10 minutes. The procedure can be canceled by switching to position 3 and then back to position 7. Audible flow noises indicate that there is still air in the pump. Should this be the case the air venting procedure needs to be repeated.
	Pump settings The circulation pump has 7 settings to choose from to accommodate different situations, position 1 being the lowest and 7 the highest setting.

Converted from the Heatweb wiki article “DHW Recirculation Pump Option”, last edited 2019-12-06. Under review for the new site.