Dimplex has described claims currently being made about some electric appliances in the market as confusing and "unachievable".
Chris Stammers, marketing director at Dimplex, said: “Some surprising
assertions with regard to efficiencies and running costs are being made
in the marketplace at the moment. But frankly, many of these claims are
unachievable, and specifiers and installers need to be able to see
through the hype, by making some straightforward comparisons.”
Dimplex said that any electric resistance heater can only ever be
100% efficient. A 1kwh input of electricty will transfer 1kw of heat
into a room for one hour, and the company said it’s not possible to
improve on that.
Not all electric heaters operate in the same way. A fluid-filled
radiator transfers the heat uniformly around the radiator, giving more
radiant than convected heat, compared with a convector heater. A slower
warm-up and continued release of heat after switch-off are also
characteristic of the fluid-filled design. But they both release exactly
the same amount of energy to the room.
Some electric radiators, filled with so-called ‘thermodynamic’ oil or
water-based fluids, claim to be more efficient and even more economical
to run than either storage heaters or panel convector heaters.
Dimplex said that neither the European Commission nor the
government’s SAP system of energy ratings recognises the claims of these
‘thermodynamic’ appliances, with both stating that the efficiency of
all electric room heaters is 100%.
When it comes to running costs, Dimplex said storage heaters that use
low-cost, off-peak electricity to heat a given property will always be
cheaper to run over a 16 hour day than direct-acting heaters which use
day-rate electricity – whether these are fluid-filled or convector