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Product information Karl

Powerful yet quiet! Karl is the first of a new generation of efficient humidifiers. Despite his low power consumption, the compact evaporator can humidify large rooms in no time at all. Karl has intelligent functions such as an Auto mode and is very easy to operate. His elegant design looks fresh and light. It fits wonderfully into any living environment. For undisturbed sleep, Karl’s LED function lights can be dimmed or switched off altogether.

Product family Humidifier
System Evaporator
Color black
Accessories (included) 1 Water Cube, 2 humidifier filters
Room size up to m² 100
Room size up to m³ 250
Capacity 690 g/h
Power level 4
Power consumption 1.4 – 30 W
Water tank capacity 4 l
Noise level 27 – 59 dB(A)
Weight 2.5 kg
Dimensions 296 x 304 x 212 mm

Awards

Karl and Karl big Reddot winner 2023
Video tutorials

Room size

For Minergie houses and flats (low-energy, energy-efficient or passive buildings) with controlled ventilation, the room size must always be doubled when selecting a humidifier. For example, if the room size is 25 m², a humidifier for Minergie buildings should be selected for rooms of at least 50 m². The reason for this is the continuous exchange of air: cold and dry outside air is warmed up and fed into the interior. The humidity in the interior is continuously transported to the outside. The result is extremely dry indoor air, especially in winter. Controlled ventilation systems act like windows that are always open, which is why the recommended room size for the humidifier should be twice as large as the room to be humidified.

Please read through the operating instructions carefully before you use the appliance for the first time and keep them safely for later reference; if necessary pass them on to the next owner.

  • Stadler Form refuses all liability for loss or damage which arises as a result of failure to follow these operating instructions.
  • The appliance is only to be used in the home for the purposes described in these instructions. Unauthorised use and technical modifications to the appliance can lead to danger to life and health.
  • This appliance can be used by children aged from 8 years and above and persons with reduced physical, sensory or mental capabilities or lack of experience and knowledge if they have been given supervision or instrucEnglish tion concerning use of the appliance in a safe way and understand the hazards involved. Children shall not play with the appliance. Cleaning and user maintenance shall not be made by children without supervision.
  • Only connect the cable to alternating current. Observe the voltage information given on the appliance.
  • Do not use damaged extension cords.
  • Do not run the power cord over sharp edges and make sure that it does not get trapped.
  • Do not pull the plug from the socket with wet hands or by holding on to the power cord.
  • Do not use the appliance in immediate vicinity of a bath tub, a shower or a swimming pool (observe a minimum distance of 3m). Place the appliance such that a person in the bath tub cannot touch the appliance.
  • Keep the device away from heat sources.
  • Do not place the appliance near a heat source. Do not subject the power cord to direct heat (such as a heated hotplate, open flames, hot iron sole plates or heaters for example). Protect power cords from oil.
  • See to it that the appliance is properly positioned to ensure a high stability during its operation and make sure that no one can trip over the power cord.
  • The appliance is not splash-proof.
  • For indoor use only.
  • Do not store the appliance outdoors.
  • Store the appliance in a dry place inaccessible to children (pack the appliance).
  • If the power cord is damaged, it must be replaced by the manufacturer or a repair shop authorized by the manufacturer or by similarly qualified persons in order to avoid a hazard.
  • Be aware that high humidity levels may encourage the growth of biological organisms in the environment.
  • Unplug the appliance during filling and cleaning.
  • Never leave water in the water container when the appliance is not in use.
  • Clean the water container every 3 days.
  • Empty and clean the humidifier before storage. Clean the humidifier before next use.
  • Warning: Micro-organisms that may be present in the water or in the environment where the appliance is used or stored, can grow in the water container and be blown in the air causing very serious health risks.
  • Only use the adapter provided by the manufacturer.
  • The appliance must not under any circumstances be operated with or come into contact with fragrances because these damage the plastic and may lead to appliance malfunctions.

Stadler Form humidifier Karl visualization of humidification

Auto mode

Karl automatically selects the appropriate humidification level in auto mode to reach and maintain the desired humidity quietly and efficiently.

Easy handling

The 4-liter water container can be easily filled through a flap opening on the top, even during operation. When the water container is empty, Karl switches off automatically.

Stadler Form humidifier Karl how to fill the water tank
Stadler Form humidifier Karl control via app

Simple operation

All functions of humidifier Karl can be conveniently controlled on the unit or via Wi-Fi using the Stadler Form app - including monitoring of the current humidity. This ensures an optimal indoor climate at home even when you are on the move.

Oskar

for rooms up to 50 m2

Karl

for rooms up to 100 m2

Karl big

for rooms up to 150 m2

Good to know

Find important information here

To ensure hygienic and optimum operation of the humidifier, the humidifier filters should be replaced at least every two months. If the humidifier filters remain in use for longer, the humidification performance may drop significantly and the antibacterial effect of the filters can no longer be guaranteed. The humidifier filters are usually available where you purchased the appliance. The filter change indicator must be reset manually after the filter change.

Slight yellowish or brownish discolouration is normal. The cause of the discolouration are the substances in the tap water or from the air. Depending on the water quality, the humidifier filters discolour more quickly. This does not look nice but is harmless as long as it is not mould. The discolouration also has no effect on the performance of your humidifier. If you have not been using the humidifier filters for long, you can rinse them, turn them over and continue with their use. If the humidifier filters are more than 2 months old, we recommend replacing them.

The humidifier filters may also become hard in the upper area. With the evaporation process, the limescale in the water settles in the humidifier filters. The harder the water, i.e. the more limescale there is in the water, the faster the humidifier filters harden. If you use water from a decalcification system that works on the principle of ion exchange, salt can settle in the humidifier filters instead of limescale. If you have used the humidifier filters for less than 2 months, you can rinse them thoroughly with water, turn them over and reinsert them. Depending on the degree of contamination of the filters with components from the air or water, odours may be emitted after turning them over. These can be counteracted by using our Hygiene Tabs.

If your appliance or the humidifier filters smell unpleasant, this can have various causes: Water and air quality, used filters or a prolonged standstill of the appliance with water in the tank. In any case, we recommend that you clean and descale the appliance thoroughly. If the filters have been in use for less than 2 months, you can rinse them thoroughly with cold, clean water, turn them over, insert and continue with their use. You should use Hygiene Tabs regularly to ensure a pleasant odour and optimum hygiene.

For hygienic reasons and to ensure proper operation, we recommend the following cleaning intervals.
Attention: Never immerse the device in water (danger of short-circuit).

Daily: Fill the device with fresh, cold tap water. If the device is not going to be used for several days, empty the water from the lower part beforehand and if necessary, clean it with a drop of washing-up liquid and a clean cloth. Fill the lower part with fresh water before putting the device into operation again.

Every 2 weeks: First remove the filters and the Water Cube™. Clean the inside of the lower part thoroughly every 2 weeks using a drop of washing-up liquid, warm water and a soft, clean cloth, sponge or brush. Then rinse out the lower part thoroughly with cold water and put back the filters and the Water Cube. As an alternative to the Water Cube, you can also use our Hygiene Tab.


Approximately every 4 weeks (depending on the water hardness in each case): First remove the filters and the Water Cube. If there are limescale deposits inside the lower part, we recommend that you use Cleaner & Descaler. Alternatively, you can use a household descaling agent or vinegar. Then rinse out the lower part thoroughly with cold water and put back the filters and the Water Cube. For hygienic reasons, the filters should be replaced every 2-3 months.

Video Cleaning

Regularly as required: To clean the outside, rub with a damp cloth and then dry thoroughly.

At the end of the season: Before putting away the device at the end of the season, clean it thoroughly inside and out and let it dry completely. Descale the lower part as described above. Clean the fan blades in the upper part with a damp cloth and then wipe them dry. Insert new humidifier filters and a new Water Cube so that your device will be ready to be put into operation at the start of the next season.

Set the output to the highest level. For the room size to be right, not only the room height (standard 2.5 m) but also whether or not the doors to the room are closed is a determining factor. If the doors to the room are left open, the adjacent rooms will also be included in the total area. If the relative humidity is low (below 35%), the humidity will not increase immediately. That is because the floors, furniture and walls absorb the moisture first before it ends up in the air. It can take up to two weeks for everything to absorb sufficient moisture for the humidity to start rising. As long as you keep having to top up the water regularly, your humidifier is working properly. If the humidifier filter is more than 2 months old or the upper part is hard and no longer saturated with water, it should be replaced.

We are currently changing the accessories that come with our humidifiers. Previously, the Water Cube was included, but now Hygiene Tabs will be included in the scope of delivery. The change is being implemented on an ongoing basis and will be handled according to the first-in-first-out principle. Therefore, during the transition phase, we cannot guarantee in advance whether you will receive Hygiene Tabs or a Water Cube with your humidifier. However, both versions ensure water hygiene in your humidifier, are functionally equivalent and compatible with the device.

Ideally, you fill your Karl using the top filling opening. Of course, you can also fill Karl at the tap, but then you must be extra careful that no water spills during transportation. 

The device can only be connected to a 2.4 GHz network. If your router does not offer a separate 2.4 GHz network, you must configure it so that it only uses the 2.4 GHz band. It is not possible to connect to a combined 2.4/5 GHz network or a pure 5 GHz network.

View complete instructions

If your Karl / Karl big is leaking, this is usually due to water getting between the inner water basin and the outer shell during filling. In this case, we recommend removing the textile cover, emptying the water, removing the filters, and allowing the unit to dry upside down. Once Karl / Karl big is completely dry, you can replace the filters and put the textile cover back on.
Ideally, you fill it using the top filling flap. Of course, you can also fill the humidifier at the tap, but you must be very careful not to spill any water during transport.
 

Different measured values can occur with different placements, heights, air flows and temperatures. The appliance measures most accurately in the centre of the room with a free flow of air. If it is positioned against the wall, a distance of at least 30 cm should be maintained. Direct contact with furniture, heaters or the sun should be avoided as they can falsify the measurement and have a negative effect on humidification efficiency. In the case of ultrasonic nebulisers with a hygrostat, the mist emitted can influence the measurement of the humidity around the device – the value displayed therefore does not always correspond to the actual humidity in the room.

The device is equipped with a practical reminder function that reminds you to change the filters in good time. After 60 days, he will automatically remind you – without you having to think about it.

Accessories

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Hygiene Tabs
CHF 16.90

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Hygiene Tabs (2 pack)
CHF 25.90

CHF 33.80

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Oskar / Karl filter (16 pack)
CHF 95.00

CHF 99.80

Save CHF 4.80

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Karl humidifier by Stadler Form as perspective view

Karl

Reviews

Average rating of 5 out of 5 stars

(2)

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Perfekt

Karl erfüllt sowohl ästhetisch als auch funktional unsere Erwartungen. In Kombination mit der perfekten Kaufabwicklung und dem sehr schnellen Versand resultiert somit eine uneingeschränkte Kaufempfehlung.

Review from Michael von Gunten at 07.02.2023

Average rating of 5 out of 5 stars

Viel Power

Schön ist er, aber auch sehr leistungsfähig. Bei mir reicht Karl für mein ganzes Wohnzimmer, welches sicher 80 Quadratmeter gross ist. Ich glaube, er könnte auch noch mehr befeuchten. Die Einfüllöffnung ist eher etwas klein und schwierig zu treffe...

Review from Max at 18.11.2022
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Karl

The Designer

Since the very start, I have had the privilege to co-develop and design products for Martin Stadler and the Stadler Form Team. What began with Fred, has grown into an attractive, small but fine range of products. This experience, and being part of the team, has greatly enriched myself and my work as a designer ...

The designer Matti Walker

Matti Walker

Learn more
Logo NYIGF Design Award 2002 for Max heater by Stadler Form Logo iF Design Award 2017 for Eva humidifier by Stadler Form Logo German Design Award 2022 air purifier Roger by Stadler Form IDA Design Award 2024 for Lukas dehumidifier by Stadler Form

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