Frequently asked questions about Oskar big
It may be that your external hygrometer and Oskar big are measuring different values because the devices are located in different positions (heights) in the room. Different humidity is measured depending on the airflow and temperature. A tolerance of +/- 5 % is normal depending on the type of device. Oskar big displays optimum humidity levels if he is positioned centrally in the room so that the room air can flow towards the sensor as freely as possible. If this is not possible, we would recommend positioning Oskar big on the wall with a clearance of at least 30 cm. Oskar big should never be “hidden” in the corner of the room or behind a sofa/piece of furniture as this may negatively affect the humidity measurement as well as humidification efficiency.
If the LEDs of the hygrostat are flashing, this indicates that the desired air humidity level has been reached and the device has switched off automatically.
You can use the hygrostat to set the desired air humidity level. To do this, press on the hygrostat button. You can choose between the following levels: 40 % relative air humidity (1 blue lamp), 45 % (2 blue lamps), 50 % (3 blue lamps), 55 % (4 blue lamps), continous operation (5 blue lamps. Please note that the hygrostat needs some time to measure the current humidity in the room.
The hygrostat switches the device on automatically once the relative air humidity in the room sinks below the preset value.
First check whether the float gauge (see A) can be moved up and down. It may be blocked due to too much limescale/dirt. Decalcify the water tank regularly to ensure trouble-free operation.
Oskar big consists of two parts: A top part and a bottom part. If the top part is not exactly in the right position on the bottom part, the float gauge sensor does not make contact with the electronics in the upper part. Position the upper part correctly to establish contact.
Should neither of these cases apply, lift off the upper part and clean the contacts (see B and C) with a damp cloth, dry them and place the upper part back on the bottom part.
Set the hygrostat at the highest setting. The size of the room, the height of the room (2.5 m) and whether the room doors are closed plays a role. If the room doors are open, the adjacent rooms are also included in the total area. With a lower relative humidity (less than 35 %), the humidity will not increase immediately. This is because the floors, furniture and walls are the first to absorb the humidity before it ends up in the air. It can take up to two weeks for everything to have absorbed sufficient humidity and for the level in the air to increase. As long as you have to refill the water tank regularly, your Oskar big is functioning properly.
Yes, both filter versions can be used with Oskar big. We have recently updated the filter to a new version that works without the plastic frame. There are two reasons for this update: First, we were able to reduce the amount of waste by eliminating the plastic frame. The new filters are made out of textile- and plant-fibre. Second, the new material allows for a higher humidification performance.
In order to clean the inside, remove the filter cassettes and rinse out the water tank. Use a soft brush or a sponge to clean the tank thoroughly. Decalcify the water tank regularly depending on how hard your water it. Rinse out the water tank thoroughly after decalcifying and dry it before operating the air humidifier again. The following video shows the correct cleaning.
For the hygienic and ideal operation of the air humidifier, the filter cassettes need to be replaced every two months. If the filter cassettes are used for a longer period the humidifying effect can be negatively impaired on the one hand and, on the other hand, the antibacterial action of the filter cassettes is no longer ensured. The filter cassettes can usually be obtained from where you purchased the unit. The following video tutorial shows the correct replacement of the filter cassettes.
During the evaporation process, the lime present in the water is collected in the filter cassettes as limescale. The amount of lime present in your water will depend on the hardness of the water. The harder the water, the quicker the filter cassettes will also become hard and will have to be replaced. Note: If you don’t know the hardness of your tap water, you can ask your local water supplier. If you use water from a decalcification system which operates based on the principle of ion exchange for your Oskar big, salt may collect in the filter cassette instead of limescale.
If the top part of the filter cassettes has become hard and they have been in use for less than 2 months, they can continue to be used in spite of this. Before you do so, you should remove the filter cassettes from your Oskar big, rinse them thoroughly with water, turn them over and put them back again – so that the part which had become hard is in the water. Note: It is possible that you may notice an odour after you have turned over the filter cassettes depending on how contaminated the filter is by constituents in the air or the water.
If the filter cassettes are more than two months old, replace them with new ones (see the question “How often do I need to replace the filter cassettes?”).
A mild yellow or brown discolouration of the filter material, mainly in the upper section, is normal. The residual water needs to be emptied if you do not use Oskar big for some time. If the evaporator cassettes are submerged in water for a longer period of time, without the fan being operated, algal growth may occur or mould may appear. To prevent this from happening, empty the device and allow the filter cassettes time to dry. Refill the water again if Oskar big is used regularly.
The substances in tap water or the air are the reason for the change in colour. The filter cassettes change colour faster depending the water quality. Although this does not look nice, it is harmless as long as it is not due to mould (filter cassettes with mould on them should be disposed of and the appliance should be cleaned thoroughly).
If you haven’t used the filter cassettes for a long time, you can rinse them well, turn them over and continue using them. If the filter cassettes are older than two months, please exchange them for new ones (see “How often do I need to replace the filter cassettes?”). Important: The discolouration of the filter cassettes will not affect the performance of the air humidifier.