Sustainably heating living spaces with large glass surfaces
Floor to ceiling windows give a sense of freedom and give you a wonderful view outside. During the autumn and winter months, however, the cold penetrates through the large glass surfaces into the room. At low temperatures, the room feels uncomfortably cool. With the Variotherm trench heating system, the room is shielded from the cold outside while being comfortably warm inside and therefore prevents the collection of condensate on the glass surfaces.
This is how a trench heating system works
The floor convectors are sunk into the floor and end flush with the floor covering. They are installed directly in front of glass surfaces. The core of the Variotherm underfloor heating system is the heating element: This is a copper pipe with aluminium louvres attached on top. Hot water flows through the pipe which heats the louvres. A veil of warm air is created along the cold glass surfaces. The cold from the outside is shielded off, while the room is comfortably warm. This physical reaction is called the Coandă effect.
It is important that the heating element is installed directly on the window side in order to effectively shield off the cold air. At the same time, the degree of air circulation remains low.
Our tip: In order for the trench heating system to end fully flush with the floor, make sure you take the finished height of the floor covering into account during the planning stage.
Where are floor trench heating systems used?
- Along large, room-height glass surfaces
- Conservatory
- New buildings
- As room heating combined with low-temperature surface heating for the floor, wall and ceiling
Requirements for trench heating systems
- The underfloor heating systems must be mounted along the entire glass surface
- Flow temperature of at least 40 °C (recommended: 45-60 °C)
One system – many benefits
Large window façades enable an unobstructed view of your garden. The floor trench heating systems very quickly shield the room from the outside cold to keep it cosy and warm during the winter. With a trench heating system, you can also keep your conservatory at a comfortable temperature and free of condensate.
The benefits for you
- Rapidly forms a veil of warm air along cold glass surfaces
- Condensate formation on the glass façades can be avoided.
- Roll and linear grids in three colours
- Low air flow – almost no dust disturbance
- Discreetly integrated into the floor, without spoiling the window appearance
- The grids can be walked over as soon as they have been installed
- A comfortable room climate, combined with low-temperature surface heating
- 10-year guarantee
Technology
This is how trench heating is constructed
The trench heating system is supplied pre-assembled, ready for installation. All components are perfectly matched to each other.
- Floor trench: Aluminium side walls and end cover (black anodised), black-grey aluminium base, air baffles, heating element mounting bulkheads, interior adjustment screws for height adjustment, green side strips, attachment brackets
- Length: Custom length (with lengths > 5000 mm, the floor trench is supplied in segments)
- Grid: Linear or roll grid, anodised aluminium, safe to walk on, standard colours: Plain aluminium (EV 1), light bronze (C 32), black (C 35)
- Heating element: Copper pipe ø 18 × 0.5 mm (DIN EN 12 449) with 56 × 78 mm aluminium louvres
The Coandă-Effect
The gentle warm air veil circulates along cold surfaces in particular. The air is better distributed and only sinks slowly in the room. There is therefore no significant air circulation.
Variotherm trench heaters are mounted directly on glass surfaces or cool walls. This enables a veil of warm air to quickly build up along the cold surfaces, leaving the cold outside.
Details and components
All Variotherm trench heating systems are delivered already pre-assembled with the correct length, and only need to be aligned and screwed into place at the designated site. Variotherm flow and return valves or 3/4″ connection angle pieces can also be optionally pre-fitted to the pre-insulated VarioModular pipe.
The supply line holes are drilled in the end cover or side walls, as desired by the customer.
Grid
Both the linear grid and the roll grid have an attractive visual design and are easy to clean. The grids are available in 3 different colours (anodised aluminium).
Heating elements
The heating elements are the technical core component of the Variotherm trench heating system. They work very efficiently and give off the heat optimally.
The heating element consists of a copper pipe ø 18 × 0.5 mm (DIN EN 12 449) with aluminium louvres 56 × 78 mm. The special manufacturing process results in a connection between the pipe and the aluminium louvres with an unsurpassed performance.
Dimensioning and layout
The dimensioning of the trench heating system depends on:
- The flow temperature
- The required output
- The possible installation length
Planning the maximum flow temperature tv of the heating system is the key to a healthy warmth provided by the trench heating system. We recommend that the set-up temperature does not exceed 60 °C. Otherwise, the louvre temperature will be significantly below the dust carbonisation temperature, which can lead to unhealthy air. Best results are achieved with maximum flow temperatures of 50 to 55 °C.
Ideal case:
Optimum cold shielding is achieved when the trench heating system is installed along the entire glass surface (floor-touching glass surfaces such as in winter gardens or terrace doors).
Recommended maximum length of a heating circuit:
- BKH1, BKH1 mini: 7.5 m (= 7.5 m heating element)
- BKH2, BKH2 mini: 5.0 m (= 10 m heating element)
Installation examples
Trench with clearance to window
Trench directly at the window
Installation
Simple and quick to install
All Variotherm trench heating systems are delivered already pre-assembled with the correct length, and only need to be aligned and screwed into place on site. Using the interior adjustment screws, the trench can be precisely set to the required floor level. Subsequent adjustments can be made at any time. No underfill is required.
After connecting the trench heating system to the heating circuit, the screed and then the floor covering can be laid. Once the linear or roll grids have been inserted, the trench heating can be walked on immediately.
All you need for installation
Heating elements developed and produced by Variotherm
Trench heating systems cause a veil of warm air, which protects the cooling effects of cold surfaces
Linear grid
Roll grid
The grids are available in pure aluminium, light brass and black
Heating/cooling manifolds are fully assembled and pressure-tested
FAQs
Where are trench heating systems mounted?
Underfloor heating systems are installed along high glass façades. They are discreet and space-saving, since they are sunk in the floor flush with the upper edge. Trench heating systems can be adapted to the room. Their length is flexible and they can be produced with a mitre joint for corners.
The heating elements are protected by roll and linear grids. They are available in three colours and can be removed at any time. This makes them easy to clean. During the summer, the grids can be replaced by cover panels in the same style as the floor covering.
Does floor trench heating have any disadvantages?
- When upgrading your heating system, a trench heating system is not ideal for installation at a later date, since the floor convectors have to be sunk in screed. However, if the screed needs to be removed, the trench heating system can also be installed subsequently.
- Flow temperatures of at least 40 °C.