Questions about our hot tubs

Everything about our hot tubs

What kind of surface can the hot tub stand on?

The hot tub requires a sturdy surface to stand on. A lawn is an option, but gravel is preferable.

Important: If you want to set up your hot tub on your terrace, please bear in mind the total weight of the hot tub incl. water and people.

How much does the hot tub weigh?

The smaller 180 hot tub weighs 200 kg when set up, and the larger 200 hot tub weighs 250 kg.

How much water can the hot tub hold?

The smaller 180 hot tub has a capacity of 1400 litres and the larger 200 hot tub a capacity of 1800 litres.

How long do I need to heat the hot tub for it to reach a water temperature of 37–40 degrees?

In general a tub filled with 1500 litres of water at an outside temperature of 0ºC takes 2–3.5 hours to heat the water to a comfortable bathing temperature of 37–40ºC. However, this depends on various factors, including outside temperature, lid type, water quantity, heating and insulation.

How long does the water in the hot tub stay warm?

The amount of time that the water stays warm depends on weather conditions, lid type and insulation, as well as the water temperature itself. Depending on these factors, the water can stay warm for 8 to 20 hours.

What happens if the outside temperature is less than 0ºC – does the water have to be removed from the hot tub?

If you use the hot tub regularly during frosty periods (approx. twice a week), you don’t need to remove the water as the core temperature will generally be above 0ºC. Heat is conserved for even longer with the optional thermal lid.

If you have a sand filter installed, you can also leave this running during frosty periods. The circulation makes the freezing temperature of the water decrease even further. 

If your hot tub is going to be ‘unsupervised’ and out of operation for several days, and you don’t have a circulation system such as a sand filter, a frost-protection monitor or an auxiliary heater, then remove the water. 

In general you should check the condition of the filled hot tub at different outside temperatures at regular intervals (water temperature, ice deposits, etc.) to avoid any lasting damage.



What whirlpool function / jet combinations are there?

Air massage, 12 valves, 0.8 kW pump:
Pumps refreshing air bubbles into the tub.

Water massages, 6 valves, 1.5 kW pump:
Water is pumped into the tub at high pressure.

Hydro/water massage, 10 valves, 1.5 kW pump:
Water is pumped into the tub at higher pressure.

Air/water combo, 12 valves:
A combination of air massages (4 valves, 0.8 kW pump) and water massage (8 valves, 1.5 kW pump).

Hydro/water/air massage 18 valves:
A combination of air massages (12 valves, 0.8 kW pump) and hydro/water massage (6 valves, 1.1 kW pump).

What happens if I heat the hot tub too much – can the hot tub catch fire or can the tub melt?

Yes, the fibreglass tub can be damaged. It can lose its shape or bubbles can form on the surface. The wood stove can also come loose if it overheats.

Approximately how much wood do I need to heat the hot tub to 37–40 degrees?

This depends on weather conditions, so it’s impossible to give an exact answer. Calculate a quantity of wood that is around 2–3 times the size of the stove.

Your stove will burn better if you add firewood every 10–15 minutes while heating it so that the fire doesn’t go out.

What kind of wood is best suited to firing the hot tub?

Ideally, fill your stove with thin, untreated spruce, firewood or pallet timber (of course you can also use other kinds of wood). The more compact the wood is, the better its energy value – and more important still is dry firewood.

How long does the warranty last on my hot tub and the individual parts?

The warranty lasts for 2 years and covers the entire hot tub incl. individual parts, as long as everything is used in accordance with the instruction manual and is not damaged intentionally. Please find more information in our terms and conditions.

What tub colours are there?

You can choose between three tub colours: White, blue and anthracite.

What is a thermal lid?

A thermal cover made of leather and containing an insulating material on the inside. The water heats up as much as 30% quicker and cools down more slowly, significantly reducing the heating-up time the next day. It stays warm for up to 60% longer.

Can the hot tub be operated electrically?

Yes, it can also be operated using the optional electric heater (3 kW or 6 kW). Ideally the wood stove would be used for heating up and the electric heating to maintain heat, as the heating-up time with the electric heating is 5–7 hours depending on its capacity.

What is a skimmer and what is it used for?

The skimmer filters dirt and impurities from the water’s surface. A chlorine tablet can also be added to the skimmer, for example, to remove unwanted bacteria.

What is the UV lamp for?

A UV lamp shines UV light on the water as it flows through. This kills off germs and bacteria and, along with the sand filter, guarantees a carefree bathing experience.

The UV lamp is located in its own water circulation system with its own pump and jet. This means that the UV filter runs independently of the sand-filter system and can also continue to operate if the sand filter malfunctions.

What products can I use for water maintenance?

For tub and water maintenance we recommend HOLZKULSIV CLEAN CARE Use and quantities are precisely to our pool sizes. Alternatively you can also use other products for water maintenance in smaller-sized pools and baths.

Do I have to maintain the wood? If yes, how often and what with?

The wood should be disinfected and oiled 2–3 times a year to prevent the formation of mould and cracks. Disinfection protects the wood from UV light and also regulates moisture. Oil provides an additional layer to protect against the elements, is dirt-repellent, and the wood retains its natural appearance. We oil the wood before it leaves our workshop.

What wood types are there? Do the different wood types require different maintenance?

We give you the choice of spruce, larch, thermowood and red cedar for the external cladding of the wood. All wood types need to be treated with colourless oil several times a year to ensure that they last longer. Spruce can also be coated with wood paint.

Can children use the hot tub unattended?

For safety reasons, do not let children in or near the hot tub unattended under any circumstances while the water is being filled and heated!

What do you need a sand filter for?

A sand filter pump removes coarse dirt by drawing water from the bathtub through the filter and pushing it through a layer of sand. The dirt is trapped in the sand, and clean water is pumped back into the tub.

How often do I need to clean the sand filter?

The sand in the sand filter should be changed twice a year, or even more frequently if needed, as well as if the sand filter contained standing water for a long period of time and smells bad.

How much electricity does the sand filter need?

The sand filter consumes 0.4 kW.

What kind of sand goes in the sand filter?

Quartz sand is most suitable.

How long should be sand filter run for each day?

The sand filter should run for 1–2 hours a day, but this depends on the water quality in the tub.

How often does the water have to be changed?

Factors like intensity of use, regular number of people, and what other filters and pumps you use all play a decisive role in how often the water needs to be changed. If you only use the hot tub at weekends, you should change the water once a week.

Why do we only install the 316 stove type?

The heating elements and applications of the 316 stainless-steel stoves are resistant to chlorinated water as well as salt- and seawater. This way we provide you with our own uncompromising quality. 304 stainless-steel stoves are only suitable for chlorinated water.

How warm can the water be at most?

You should not exceed a heat of 40–45°C, as otherwise you risk damaging your hot tub.

Note on the material of the drinks shelf

Generally the drinks shelf is delivered in spruce and coated to match the colour of the wood used for the hot tub.

Note on the substructure, steps and sand filter box

The substructure for the steps and sand filter box is made of pressure-treated solid wood for all models delivered.