Daikin EWAP460MBYN [239/452] Pump control

ESIE05-07 Functional Control for a Standalone Unit

Part 2 – Functional Description 2–43

2.9 Pump Control

Introduction To prevent the chiller to start up without flow, safety checks are performed.

First there is a check to make sure that water flows through the system.

If a second evaporator pump is installed a second safety check is performed: the double evaporator

pump control, in case of failure of one pump the other one takes over.

Another advantage of this control is the fact that the system switches from one pump to the other in

case failure during operation.

The status of the condenser pump can also be indicated via the changeable relay outputs.

Pump lead/lag time The PUMPCONTROL of the user settings menu allows the user to define the pump-lead time and

pump-lag time.

Remark: The default value for the PUMPLAGTIME is 0 s but it is recommended to set the lag time to

120s. This is to prevent the evaporator from freezing up.

Daily pump startup The user will get the choice to perform a pump start every day to prevent obstruction of the pump and

to increase its lifetime. Everyday at pump start time, which can be set in the timers menu, the pump

will be started automatically for a short period (5s) if the unit is off.

If dual pump control is selected by changeable digital output, then it is also possible to start up this

pump in the service menu.

Line n° Display Description Default value Limit values

1 PUMP CONTROL Screen title

2 PUMPLEADTIME Time the water pump will

run before starting up the

chiller

020 s 020-180 s

3 PUMPLAGTIME Time the water pump will

keep running after stop-

ping the chiller

000 s 000-180 s

Line n° Display Description Default value Limit value

4 DAILY ON Activation of daily pump start N N-Y

4 AT Daily pump start up time 12h00 00h00-24h60

ESIE05-07.book Page 43 Wednesday, October 11, 2006 10:42 AM