8.4 Cooling Function
Place switch (1) in position On (I) to put heat pump into operation. The cooling mode can be preselected by placing switch (2) to the Cooling (
) position. The desired return temperature can be set using selector dial (4), the relevant call for heat is controlled by the potentiometer and lies within a range of min. 12 °C and max. 25 °C. When the preset temperature is reached, the heat pump switches off. Once the return temperature exceeds the preset value by 4 Kelvin, the heat pump switches back on. The heat pump cannot be restarted until a minimum time delay of 5 minutes has elapsed. At a supply temperature of below 7 °C, the heat pump switches off.
To prevent condensate from forming on the system in the case of surface cooling systems, it is recommended that dew point monitors be installed at critical places of the cold distribution system and connected in lieu of jumper A1. In the event that condensation should form, the cooling operation of the system will be interrupted.
FUNCTIONAL DESCRIPTION
CLEANING / CARE
9 CLEANING / CARE
9.1 Care
To protect the paint finish, avoid placing objects against or on the unit. The external parts of the heat pump can be wiped with a damp cloth and commercially available cleaning agents.
CAUTION! Do not use any cleaning agents containing sand, soda, acid or chloride as these may damage the surface.
To prevent malfunctions due to dirt deposits in the plate heat exchanger of the heat pump, care must be taken that the heat exchanger cannot become contaminated in the heating installation. In the event that operating malfunctions due to contamination occur nevertheless, the system should be cleaned as described below. (Caution: The fins of the finned heat exchanger have sharp edges
8.5 Domestic Hot Water Function
This heat pump can also be used for heating domestic water.
The call for domestic water heating (and the domestic water temperature) is controlled by terminal
A suitable thermostat is available as an accessory.
The call for domestic water heating may also occur if no call for space heating exists. On a call for heat, the control unit switches off the heating circulating pump and the setpoint is set to maximum.
The water temperature is now controlled by the external thermostat. After the domestic hot water preparation has been terminated, the system returns to the same function that was active before the call.
9.2 Cleaning of Heating Side
The ingress of oxygen into the heating water may result in the formation of oxidation products. An ad- ditional contamination of the heating water caused by residues of lubricating and sealing agents occurs in many cases.
Both of the above causes may lead to a reduction in the performance of the plate heat exchanger of the heat pumps. In such cases, the installer must clean the heat exchanger concerned. Based on information known to date we recommend cleaning with a 5% phosphoric acid solution or, in the case that cleaning needs to be performed more frequently, with a 5% formic acid solution. In both cases the cleaning fluid should be at room temperature. Thorough flushing is necessary to ensure that all cleaning agent residues are removed from the system. It is recommended that the heat exchanger be cleaned in the direction opposite to the normal flow direction. Owing to their acid content, flushing agents must be used with caution. To prevent acidic flushing agents from entering the heating installation when cleaning the condenser, we recommend that the flushing device be mounted directly to the supply and return line of the heat pump. The regulations of the trade associations must be adhered to. If in doubt, contact the manufacturers of the chemicals!
CAUTION! To prevent consequential damage it is imperative that the water circuit be neutralized after cleaning using appropriate agents.
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