Lodam LMC 320, Руководство пользователя, Страница: 26 / 68

26 User Manual - Lodam Heat Pump Controller
Ver
. 1.0 - 11.10.10
frost at low ambient temperatures the LMC320 is equipped with an
automatic defrost system.
The defrost method can be Air, Hot gas, Auto or Off . Air means
only the fan is used for melting the ice in the evaporator.
Hot gas
uses a hot gas/bypass valve to let the hot gas from the discharge side
of the compressor though the evaporator and thereby melting the
ice from the “inside”. In
Auto mode hot gas is only used at ambient
temperatures below 3 °C. Off is used to disable automatic defrost.
The settings are accessible on the Installer – Defrost settings menu
where the different settings are also described.
Safety cut out
There are three safety cut outs:
High pressure The controller will attempt 3 restarts before user
intervention is needed
Low pressure The user must acknowledge the alarm for starting
again
Brine leakage The user must acknowledge the alarm for starting
again
Sensor monitoring
The sensors are monitored against short circuit or lost connection
and the appropriate alarm is set. Please see section Alarm system
and trouble shooting for a list of alarms and how to trouble shoot an
alarm.
Hot side pump control
The relay for the hot side pump can be used for different
configurations. However the hot side pump is running together with
the compressor except during defrosting. This pump is also motioned
during pump exercises.
Cold pump control
After the heat pump has stopped, the fan / brine pump will run
another 1 min to ensure there evaporator temperature is stabilized.
The next compressor start will have lower pressure difference across
the compressor and give less mechanical wear on the compressor.
At start up of the heat pump, the fan / brine pump starts a little later
Functions