The TM-RV series.

Multi-way dehumidifier with valves for indoor, outdoor & offshore use according to ATEX

GIEBEL Adsorber® of the TM-RV series are reusable dehumidifiers especially for transformers. They are suitable for indoor, outdoor and offshore use.
The stainless steel housing is filled with GIEBEL Xdry®. The desiccant mixture ensures effective drying of the supply air. In addition, the dehumidifiers have a stable valve part and an oil reservoir. When the adsorber is saturated, both desiccant and, if necessary, all other internal components can be replaced at low cost.
The suspended version is available with all common connections for transformers. The series features an activated carbon layer to separate escaping oil mist. This ensures cyclic self-regeneration and thus very long maintenance intervals. The adsorbers can be used in zone II 2 G / D IIC T4 according to the ATEX product directive 2014/34/EU and meet the criteria of corrosivity category CX.

Mode of operation.

Adsorption – drying of the supply air

  • The filling level of the system decreases
  • Humid air is sucked in
  • Valves open at approx. 6 mbar
  • Uniform flow through the adsorber
  • Air is dried to 2% rH
  • GIEBEL Xdry® discolors as saturation increases
  • Air is filtered to 2μm

Dry and clean supply air

Desorption – separation of oil particles

  • The filling level of the system increases
  • Dry, oily air is squeezed out
  • Activated carbon absorbs the oil mist
  • Dry, oil-free air regenerates the desiccant
  • GIEBEL Xdry® partially recovers its color

Self-regeneration and oil-free exhaust air

Technical data.


The sucked-in air opens the valves in the lower part of the adsorber already at approx. 6 mbar. After flowing into the adsorber, the air is evenly distributed over the cross-section. The pre-filter disc frees the air from coarse dirt particles.

When flowing through the desiccant, the water molecules are reliably removed from the air. The gap volume of the granulate is optimally selected with 2 to 5 mm grain size and guarantees a minimum pressure build-up with very good drying efficiency at the same time. Thus, a residual air humidity of max. 2 % rH and a dew point of -40 °C are achieved at the beginning of the drying process. A 2µm particle filter ensures that all dirt particles are separated from the ambient air and the GIEBEL Xdry® fill and that the connected plant is not contaminated.

When air is discharged, the 2 µm particle filter and a layer of activated carbon prevent oil particles and oil mist from entering the desiccant, thus enabling the adsorber to self-regenerate.

As saturation increases, the orange silica gel grains of the GIEBEL Xdry® fill turn green. If the silica gel grains have turned completely green, the adsorber must be replaced.

Pressure ratios.

Spare parts kits.

Sustainability starts with using product components for as long as their life cycle allows and replacing only those components that show signs of wear. With our spare parts packages for the refillable adsorber series, we ensure that you can replace each individual component of an adsorber as needed.

For example, the desiccant in our adsorbers becomes stressed over use, increasingly losing its ability to adsorb moisture and requiring replacement, while the adsorber housing is particularly durable. Our refillable adsorbers can therefore be easily opened to replace the desiccant. Seals, particle filters and activated carbon disks can withstand a few replacement cycles, depending on the load. However, we recommend replacing them after 4-5 replacement cycles at the latest to ensure smooth operation of the adsorbers.

Our spare parts packages include gaskets, particle filters, activated carbon discs and other components matched to the respective adsorber series. The matching desiccants for the adsorbers are available separately and in various size units.

Adsorber Spare parts kits