Issue
- Which types of tumble dryers are available in the market?
- What are the main differences between tumble dryers?
- Which dryers are the most effective in terms of energy consumption?
Applies to
- Tumble Dryers
Resolution
There are three main types of Household Tumble Dryers sold on the market:
Condenser Dryer with Heat Pump Technology - Most efficient in terms of energy consumption.
- Drying air is heated by the hot side of the heat pump.
- Hot air passes through the load and causes water evaporation.
- Water vapour is condensed by the cold side of the heat pump and collected into a reservoir or directly passed to the drain pipe.
- The heat pump's hot side re-heats the air afterwards for reuse, which conserves much of the heat within the dryer.
- A portion of the water vapour and heat leaks outside and increases the ambient temperature.
- After some time air in the internal loop is warmer and more humid which can increase the drying time.
- Heat re-circulation is the big advantage of this type of dryer, with a positive effect on energy consumption.
- Drying air is heated by the heater.
- hot air passes through the load and causes water evaporation.
- Water vapour is condensed by the heat exchanger and collected into the reservoir or directly passed to the drain pipe.
- The heat exchanger is cooled by the forced stream of ambient air.
- A portion of the water vapour and heat leaks outside and increases the ambient temperature.
- After some time in operation air in the internal loop is warmer and more humid, which can increase drying time.
Exhaust Dryer with Heater
- Drying air is heated by the heater.
- Hot air passes through the load and causes water evaporation.
- Hot air carrying water vapour is exhausted outside the room through the ventilation hose.
- Heat is wasted, causing high energy consumption and hence high drying costs.
- After some time air in the internal loop is drier, decreasing drying time.
Tumble Dryers Comparison:
Condense Dryer with Heat Pump | Condense Dryer with Heater | Exhaust Dryer with Heater | |
energy consumption | lowest | low | above average |
drying temperatures | low | high | high |
drying delicacy | *** | * | * |
drying cycle time | *** | ** | * |
energy saving* | *** | * | ------ |
performance drying cost | *** | * | * |
* compared to exhaust dryers
