Storage room

The optimal storage of the pellets depends on your spatial conditions.

This means we have unrivalled know-how and an unsurpassed range of solutions for adapting cellars and other rooms for pellet storage.

We can provide advice on every aspect of storage, from the correct amount of space for your system through to all-inclusive solutions with bespoke floor plans and automated pellet transport to the boiler.

Information and tips for the planning of pellet heating systems with storage room

The size of the storage room

The total heat load of a building determines the ideal size of the required storage room. As a rule of thumb, the following formula can be used: each 1 kW heat load = 0.9 m3 storage space (including voids). In principle, it is better if the storage room is rectangular and no wider than two metres. The narrower the room is, the lower the inbuilt inclines will be and the more space can be used.

Sloping floor

A sloping floor is the ideal configuration for a pellet store, allowing the space to empty completely. Not only does this allow for the maximum efficiency in feeding the fuel to the boiler, but it removes the need to clean the store room manually each year by avoiding a build-up of unused pellets. With a sloping floor, the pellets slide to the delivery auger in the centre of the store. ÖkoFEN can supply angle brackets designed to give the optimum angle for a sloping floor substructure.

The location of the storage room

The storage or heating room should preferably be adjacent to an external wall in order to be able to easily install the blow-in, suction and ventilation pipes. In internal rooms, however, these pipes can also be led up to the outer wall. No light switches, sockets, lights or distribution boxes may be installed in the pellet storage room.

Storage with vacuum suction system

Pellet storage and heating boiler up to 20 meters away.

Location of the wood pellet storage and the boiler room

Pellets are delivered by tanker truck and are blown into the storage room or the FlexiTank. The truck's pumping hose is max. 30 m length, so the filler coupling must be no more than 30m from the drive, parking space or road.

If possible, the FlexiTank room should border at least one exterior wall, since the filler coupling must be accessible from the outside. Where this is not possible, ventilation and filling pipes must be routed to a filler coupling on the outside of the building. (Attention - in some countries fire regulations must be observed).

The boiler room should also have at least one exterior wall in order to allow direct ventilation. For boiler rooms which do not border an exterior wall, a ventilation pipe (at least 200 cm²) must be routed to an exterior wall.

Humidity

Dry indoor conditions are a prerequisite, since the pellets would swell and became useless in contact with damp walls. In damply areas, we recommend to use our Flexilo textile silo.

Electrical requirements

No light switches, electrical outlets, light bulbs and distribution boxes, etc. are allowed in the pellet storage room.

Size of the wood pellet storage and the boiler room

Basically, the wood pellet storage room should be elongated rectangular, with a room width - if possible - no more than 2.0 m:

i.e. W: 2 m x 3 m or 1,8 m x 3,2 m etc.

The narrower the room, the less unused empty space. The size of the required storage room depends on the building heat demand. The following rule of thumb may be applied:

per 1 kW heating load = 0,9 m³ Storage room (including unused empty space)

For example:

One family house with a heat load of 10 kW = 4.000 kg wood pellet annual requirement

How do I fit up my boiler and pellet room?

Ventilation

Every pellet storage room or installation room for finished storage must be ventilated. The ventilation openings should be designed so that they do not open directly under windows or supply air openings. Ventilation can be provided either via ventilated filling couplings or separate ventilation openings.

Walls:

The enclosing walls must be able to withstand the static requirements of the weight load from the wood pellets (bulk weight approx. 650 kg/m³). The storage room walls and their anchoring in the surrounding masonry must be constructed properly and professionally in accordance with the rules of technology. Ceilings and walls must be designed in such a way that the wood pellets are not contaminated by abrasion or detachment.

Doors:

As with all other heating systems, the boiler room and the storage room doors must be fired proof (at least T 30). They must open outwards and fitted with a seal.
The pellet storage room door shall be provided -inside of the door opening- with wooden planks, so that the pellets do not press against the door.

Sloping floor:

In order to empty the pellet storage room, it is necessary to install an sloping floor in the storage room. ÖkoFEN offer angle brackets to facilitate the construction of the sloping floor structure.

Filler coupling with closing lid:

The pellets are blown directly into the storage room and the discharged air is evacuated. This requires two "filler couplings" with a lid. (1 x blow + 1 x evacuate)

These couplings including extension pipes, curve pieps and other accessories, are supplied by ÖkoFEN together with the heating system. A wall opening with a diameter of 125 to 150 mm must be prepared on site. It is recommended to use a PVC pipe with a diameter of 125 to 150 mm fixed to the brickwork. The filling couplings are then foamed in the prepared openings. The filler couplings must be connected to the brickwork (grounding).