Dehumidifiers: Construction, Compact and Desiccant Models

Refrigerant (compressor) dehumidifiers work well in heated or moderately warm spaces: compact models for basements, garages and flats, construction models for drying sites. Desiccant dehumidifiers also perform at low temperatures, in unheated buildings and warehouses in winter. Read refrigerant and desiccant dehumidifiers.

Capacity shows how many litres of water a dehumidifier removes per day. Compare models under the same conditions, for example 30 °C and 80 % or 27 °C and 60 % humidity, as on a real site the result depends on temperature and humidity. See what is performance or output.

Choose a dehumidifier by room area or volume and the amount of wet surfaces. High airflow (m³/h) speeds up drying of walls and floors, and running it together with an electric heater raises the efficiency of a refrigerant unit.

Check the operating temperature range. At low temperatures the evaporator of a refrigerant unit ices up, so for unheated spaces choose a model with automatic hot-gas defrost or a desiccant unit.

Compact models collect water in a tank and switch off when it is full, while continuous hose drainage matters for long unattended operation. In basements and wherever water cannot drain by gravity, a built-in condensate pump is useful.

A built-in humidistat holds the set humidity and switches the unit on and off automatically. An hour counter helps track drying and rental time, and auto-restart after a power cut matters for unattended operation.

Compact dehumidifiers draw a few hundred watts and construction models about 0.4–1.5 kW, running on 220 V. If several dehumidifiers and heaters share one circuit, check the total load, and in living spaces consider noise too. See how to choose tool power (W), volt (V) and what is noise level in db.

For building sites, choose a model with a rugged metal or rotomoulded housing, wheels and a handle. Transport a refrigerant unit upright, clean the filter and tank regularly, and in damp rooms use an earthed socket and a protected connection. Read what is an IP rating, how to use an extension cord safely, how to use fans and dehumidifiers safely and essential power tool safety rules.