Optima Company 600 - 1700 - Manual (Page 10)

10
Control unit Rego 800
The control unit makes sure the heat pump gives the best energy savings
and that it runs for many years. The control unit controls and monitors the
heating and hot water supply in your house. The monitoring function is es-
pecially important, it shuts down the heat pump in the event of operational
disturbances so that no critical parts are damaged.
Additional heat gives more output
Additional heating is required when the heat pump is unable to meet the
heating requirements or when it has stopped due to an outdoor temperature
that is too low. The additional heat is provided by an electric cassette,
existing electric/oil-fi red boiler or electric boiler 290 A/W (Optima 600-
1100). Note that when the heat pump is running, the additional heat source
only supplies the power that the heat pump cannot produce. When the heat
pump is once more able to meet the heating demand, the additional heat is
automatically switched off.
Hot water is given priority over heating water
In a house with water based heating a difference is made between heating
water and hot water. The heating water is for radiators and underfl oor coils
and hot water is for showers and taps.
When electric boiler 290 A/W is included, hot water is heated in the electric
boiler’s hot water heater. When the electric cassette or existing electric/oil-
fi red boiler is included, an external hot water heater can be connected.
In both cases, there must be a sensor, which detects the temperature of
the hot water. The heating water passes through the hot water cylinder’s
outer shell and heats up the hot water heater’s inner tank. The control unit
makes sure the heating of hot water is given priority over the heating of the
heating water.
Control unit
Automatic defrosting
Ice may form on the evaporator at outdoor temperatures below +10ºC.
When ice forms to an extent that it obstructs the air fl ow through the evapo-
rator automatic defrosting starts. Defrosting is controlled by a four-way
valve. The valve reverses the fl ow of the refrigerant in the circuit so that the
hot gas melts the ice on the evaporator fi ns. See Refrigerant fl ow in defrost
mode
in the fi gure under the heading How a heat pump works.
There is also a fan defrost function, which means that hot air blows upwards
through the fan to prevent it freezing solid.
Heating
water
Hot water