Dimplex has successfully defended four statements in a leaflet about its electric storage heaters after someone complained to the advertising watchdog that they were misleading.
The publication, downloadable from Dimplex's website, contained a list of 'Electric Storage Heating Facts', amongst which the complainant challenged: 'The performance of a Dimplex storage heater will not deteriorate over time', 'Running on off-peak electricity Dimplex storage heaters will always be cheaper over a 16 hour day than direct acting heaters on the day-rate', 'Dimplex storage heaters, like other electric space heaters are 100% efficient - unbeatable by traditional heating methods' and 'Static Dimplex storage heaters have no moving parts and are maintenance-free for life'.

Investigating the first claim, that the performance of a Dimplex heater would not deteriorate over time, the Advertising Standards Authority agreed that the product would always function at an efficiency rate of 100% from electricity to heat. It said it also understood that the passive components in the heater had been designed to function at the same level for the lifecycle of the product.

It also thought Dimplex's assertion that storage heaters were cheaper to run was fair. "Because we understood that storage heaters were able to make use of off-peak electricity tariffs to deliver heat during the day where direct acting heaters were not, and because off-peak time-of-use tariffs were by their nature cheaper than the on-peak day rates, we concluded that the claim was not misleading," it said.

On the third point, that Dimplex storage heaters were 100% efficient and unbeatable by traditional heating methods, the ASA said it understood that the comparison referred to fossil-fuelled appliances, which was also likely to be the average consumer's interpretation of the phrase 'traditional heating methods'.

It noted that the generation of grid electricity mostly relied on the burning of fossil fuels, and so the conversion losses to which traditional, fossil-fuelled heating appliances were subject would still occur when electric storage heaters were used - but at the power station rather than in the home. It therefore decided that the claim related to the individual user's experience of the heaters.

Finally, the ASA looked at the claim that Dimplex storage heaters had no moving parts and were maintenance-free for life. It acknowledged that the heaters did in fact have some moving parts but said they would not routinely move during the operation of the appliance. And while some components might fail prematurely, the average consumer was likely to be aware of that and would interpret the claim 'maintenance-free for life' as referring to regular servicing and maintenance required to keep the appliance working effectively.

The ASA decided that none of the claims was misleading.