Independent testing of the floor heating element from Coldbuster Floor Heating Australia reveals an initial heating rate of a lightning fast 2.5°C per minute.

Conducted by Bridgestone Underlay's manufacturing plant in Dandenong, Victoria, the 9-day test was done on top of the luxurious underlay, Airstep Australia in an open hallway with the key objective being to investigate if the underlay would fail under maximum temperature working conditions.

The surface temperature was measured for both extremes of thick and thin grade carpet, in order to make the test more relevant for the wide range of carpet products on the market. The heater was connected to the electrical supply without thermostat temperature control.

The heating cable reached 37°C in just 10 minutes from a 'cold start' of 13°C, with the temperature of both carpet surfaces reaching a comfortably warm 20°C. After two hours, the carpet temperature reached a steady state maximum of 30°C. The ambient air temperature remained mostly unchanged at around 15°C across all 9 days. There is a correlation between the ambient and heater element temperatures, confirming the benefits of thermostat temperature control.

Since the test was conducted in an open hallway, the ambient air temperature could not be expected to rise. At 250W the Coldbuster heater was the smallest model available, used for the purpose of testing the durability of the underlay, though this model is not of adequate size or output to achieve heating of the air for the area of the hallway. This is also reflected in the carpet surface temperature, with good insulation allowing the carpet surface to reach its maximum of 30°C much sooner.

Conclusions from the Airstep study of the Coldbuster carpet heater:

  • The heating element reached a maximum temperature of 44°C without thermostat temperature control
  • The steady state carpet surface temperature varied between 31°C  and 33°C (hotter directly over the element)
  • The underlay and carpet showed no form of deterioration, i.e. no burn marks, scorching, bulging, delaminating or discolouration
  • The Coldbuster carpet heaters (all rated 160W/m²) are compatible with Airstep’s underlay, and consequently all foam grades of underlay, being similar to the Stepmax underlay used.
Interestingly, the test also shows that the thickness of carpet used has no noticeable effect on either the warm-up time or maximum surface temperature achieved. Coldbuster suggests this would have more to do with a carpet’s insulation properties. A heavy, insulating object will slow down the warm-up time, and without thermostat temperature control, may cause overheating and consequently, discolouration of the carpet.