Description of the split system
External air is blown by a fan through the evaporator, which is installed separately from the heat pump. The advantage of split air/water heat pumps from OCHSNER is that the heat pump (compressor, condenser, electronics) is installed in the building where it is protected from the weather. Any servicing work that may be required in winter is also more convenient and safer. Heat is generated in the immediate vicinity of the heat utilisation system so it can be transferred to the heat distribution system with no losses.
With split systems the evaporators are fitted with extremely low-noise axial fans. They are installed outdoors. They are connected to the heat pump via coolant lines, with no need for expensive and noisy air ducts. The use of the non-flammable safety refrigerant R 407 C means that the system can be safely installed in any location. No frost protection is required, as the coolant in the evaporator cannot freeze even if the system is shut down for extended periods.
Split evaporator installation
The evaporator must be sited so that the air flow is not obstructed on any side. No more than one side adjacent to a wall, with a minimum clearance of 1 m if possible. Minimum clearance of 3 m above the evaporator. Avoid siting it in a hollow. The distance between the heat pump and the split evaporator is normally up to 10 m (horizontally), although a distance of up to 20 m is possible by request. The maximum height difference (vertical distance) is 10 m or up to 20 m by request. Both the horizontal distance and the height difference between the heat pump and the split evaporator should be as short as possible. The evaporator is fitted with a fully automatic hot gas defrosting device. A frost-proof collecting tray should be provided for the discharge of condensation water.
Where possible a collecting trough should be created underneath the evaporator to capture the condensation water. If a collecting tray cannot be provided, then the evaporator should be mounted on a layer of ballast. Ice may form in winter in the drainage area.
Installation on a flat or pitched roof is possible. For roof installation appropriate access aids and guards must be provided by the customer in accordance with health and safety regulations. The coolant riser must be designed and installed in accordance with the regulations.
NB: When installing the split evaporator, remember that it needs to be accessible all year round (so appropriate provisions must be made for roof installation in particular).
- Max. connection length 20 m
- Max. height difference between evaporator and heat pump 10 m, evaporator must not be lower than the heat pump
- Max. 8 bends (to be formed using a bending tool, not your knee)
- 1 m bending radius is classed as a straight section
Connecting lines to the evaporator
The connecting lines to the evaporator (intake line and fluid line) and the power supply to the fans must be laid in a penetration sleeve and thermally insulated in accordance with the regulations (defrost function). An incline is necessary to allow condensation to drain away. The connection to the evaporator must be carried out by members of the OCHSNER customer service team.
The penetration sleeve must be a smooth-walled pipe with a minimum diameter of 150 mm and must be laid with a large bending radius (over 1 m). 90° bends are not permissible.