Dehumidifier test results fall below manufacturers' claims

PUBLISHED : Saturday, 13 February, 2010, 12:00am
UPDATED : Saturday, 13 February, 2010, 12:00am

Disappointment may await some dehumidifier owners in this cool but humid time of year: their clothes may stay damp despite a long wait.

The Consumer Council has found that the dehumidifying capacity of half of the machines it tested was exaggerated by manufacturers.

Twelve dehumidifiers from 10 brands were tested. Six did not absorb as much water as they claimed, with the difference ranging from 5 per cent less in a Mitsubishi Electric model to 16 per cent less for a Panasonic.

The watchdog received eight complaints last year. One was from a man annoyed after he saw in the tank of his machine just three litres of water after he had had it on for a day. The manufacturer claimed the daily dehumidifying capacity was 10 litres.

All manufacturers were found to adopt test conditions in their favour to measure the dehumidifying capacity of their products, the council said.

Nine products were tested at 30 degrees Celsius and 80 per cent relative humidity. The other three were tested at even higher temperatures or relative humidity: 32 degrees Celsius or 85 per cent relative humidity.

That might not truly reflect the normal indoor environment when dehumidifiers are used in homes. The temperature is likely to be cooler. And most people close the windows after switching on the machines, so the humidity gets much lower when the dehumidifiers have been running for an afternoon or so.

When the watchdog tested a Neo Max model at 26 degrees Celsius and 60 per cent relative humidity - a standard adopted by the United States-based Association of Home Appliance Manufacturers - its dehumidifying capacity was 150 per cent lower than the manufacturer's claim.

And the different standards used by manufacturers for testing of the products makes it difficult for consumers to compare different brands, the council says.

The Electrical and Mechanical Services Department should encourage manufacturers to adopt a standard test environment, the council says.

Relative truth

All manufacturers were found to adopt test conditions in their favour

A Neo Max model tested at a standard adopted in the US was found by the council to have a dehumidifying capacity this much lower than claimed: 150%